Relationship of the membrane ATPase from Halobacterium saccharovorum to vacuolar ATPases.
AuthorsStan-Lotter H, Bowman EJ, Hochstein LI
JournalArch Biochem Biophys
PubMed ID1824911
Polyclonal antiserum against subunit A (67 kDa) of the vacuolar ATPase from Neurospora crassa reacted with subunit I (87 kDa) from a membrane ATPase of the extremely halophilic archaebacterium Halobacterium saccharovorum. The halobacterial ATPase was inhibited by nitrate and N-ethylmaleimide; the extent of the latter inhibition was diminished in the ... More
Prelysosomal acidic vacuoles in Dictyostelium discoideum.
AuthorsPadh H, Lavasa M, Steck TL
JournalJ Cell Biol
PubMed ID2466039
'We have examined the ameba Dictyostelium discoideum for evidence of a discrete, prelysosomal, acidic receiving compartment in endocytosis. We observed in the cytoplasm abundant round vacuoles with diameters up to 2 microns that concentrated acridine orange by a process inhibited by 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole (NBD-Cl). They were therefore taken to be acidic. ... More
Differences between the electric fields of the catalytic sites of papain and actinidin detected by using the thiol-located nitrobenzofurazan label as a spectroscopic reporter group.
AuthorsBrocklehurst K, Salih E, Lodwig TS
JournalBiochem J
PubMed ID6378189
'The catalytic-site thiol groups of papain (EC 3.4.22.2) and actinidin (EC 3.4.22.14) were each labelled with the nitrobenzofurazan (Nbf) chromophore by reaction with 4-chloro-7-nitrobenzofurazan at pH 4.4. The electronic-absorption spectra of both labelled enzymes were determined in aqueous solution, in the pH ranges approx. 2-5 for S-Nbf-papain and approx. 3.3-8 ... More
Structural organization of chloroplast coupling factor.
AuthorsSnyder B, Hammes GG
JournalBiochemistry
PubMed ID2859887
'Fluorescence resonance energy transfer measurements have been used to construct spatial maps for the accessible sulfhydryl of the gamma subunit (dark site) and the essential tyrosine residue of the beta subunits relative to previously mapped sites on the H+-ATPase from chloroplasts. The extent of energy transfer was measured between a ... More
Detection of conformational changes in chloroplast coupling factor 1 by 8-anilino-1-naphthalene-sulphonate fluorescence changes.
AuthorsPick U, Finel M
JournalEur J Biochem
PubMed ID6225641
'Chloroplast coupling factor 1 (CF1) contains a high-affinity binding site for 8-anilino-1-napthalene sulphonate (ANS,Kd = 5-6 microM). The binding of ANS to the enzyme is associated with a fluorescence enhancement and a blue-shift in the emission spectrum. ANS only slightly inhibits ATP hydrolysis by CF1. Adenine nucleotides and inorganic phosphate ... More
Diffusion, patching, and capping of stearoylated dextrans on 3T3 cell plasma membranes.
AuthorsWolf DE, Henkart P, Webb WW
JournalBiochemistry
PubMed ID6157402
'Fluorescence-labeled trinitrophenylated stearoylated dextrans have been used as controllable analogues of cell membrane proteins on model membranes and on a variety of natural cell membranes. This paper reports their behavior on 3T3 mouse fibroblast plasma membranes. Spatial distribution on the membrane was studied by fluorescence microscopy, and molecular mobility was ... More
Isolation and characterization of mitochondrial F(1)-ATPase from crayfish (Orconectes virilis) gills.
AuthorsLi Z, Neufeld GJ
JournalComp Biochem Physiol B Biochem Mol Biol
PubMed ID11207445
'A soluble F(1)-ATPase was isolated from the mitochondria of crayfish (Orconectes virilis) gill tissue. The maximal mitochondrial disruption rate (95%) was obtained by sonicating for 4 min at pH 8.6. A 15-fold purification was estimated. The properties for both soluble and membrane-bound enzyme were studied. Both enzyme forms were stable ... More
Actin and phosphoinositide binding by the ActA protein of the bacterial pathogen Listeria monocytogenes.
AuthorsCicchetti G, Maurer P, Wagener P, Kocks C
JournalJ Biol Chem
PubMed ID10559250
'The surface protein ActA of the pathogenic bacterium Listeria monocytogenes induces actin-driven movement of bacteria in the cytoplasm of infected host cells and serves as a model for actin-based motility in general. We generated and purified soluble recombinant fragments of ActA and assessed their ability to interact with the acidic ... More
Characterization of the uptake and toxicity of a fluorescent thiol reagent.
AuthorsOlive PL, Biaglow JE, Varnes ME, Durand RE
JournalCytometry
PubMed ID6839884
'3-(4-Maleimidylphenyl)-4-methyl-7-diethylamino coumarin (CPM), is a fluorescent thiol-binding agent. CPM is nontoxic to Chinese hamster V-79 cells (2 x 10(5) cells/ milliliter) exposed to 2.5 micrograms/milliliter for 30 minutes. However, both toxicity and cellular binding were directly dependent on the drug:cell ratio. Using flow cytometry, cellular binding of CPM correlated with ... More
Does fluorescence of 4-nitrobenzo-2-oxa-1,3-diazole incorporated into sarcoplasmic reticulum ATPase monitor putative E1-E2 conformational transition?
AuthorsWakabayashi S, Imagawa T, Shigekawa M
JournalJ Biochem (Tokyo)
PubMed ID2141602
'When a purified preparation of sarcoplasmic reticulum Ca2(+)-ATPase was labeled with 0.3 mM 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole (NBD-Cl) in 1 mM AMPPNP and 1 mM CaCl2 at 25 degrees C and pH 7.0 for 60 min and then was treated with 10 mM dithiothreitol for 7 min, about 1 mol of NBD was ... More
[Analysis of volatile nitrosamines in food of animal origin]
AuthorsFritz W, Uhde WJ, Donath R, Buthig C, Schütze E
JournalNahrung
PubMed ID7412855
'A method is described for the fluorescence-spectrophotometric densitometric determination of nitrosamines. For this purpose, foods of animal origin are vacuum-distilled, the distilled-over nitrosamines are extracted with methylene chloride from an acid medium and, after cleavage by hydrogen bromide, the corresponding amines are reacted with 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole. The purificaton of the extract ... More
Geometric isomers of covalently labeled mitochondrial F1-adenosinetriphosphatase with different properties.
AuthorsWang JH, Joshi V, Wu JC
JournalBiochemistry
PubMed ID2879562
'Two geometric isomers of covalently labeled F1-adenosinetriphosphatase (F1-ATPase) have been prepared by reaction with 7-chloro-4-nitro-2,1,3-benzoxadiazole (NBD-Cl): a directly labeled product denoted by O-beta''-NBD-F1 and an indirectly prepared product denoted by 0-beta''-NBD-F1. The normal isomer O-beta''-NBD-F1 is highly inhibited, and its label can be removed by 20 microM N-acetyl-L-cysteine (AC) at ... More
Interactions of dihydroxybenzenes with the Ca(2+)-ATPase: separate binding sites for dihydroxybenzenes and sesquiterpene lactones.
AuthorsKhan YM, Wictome M, East JM, Lee AG
JournalBiochemistry
PubMed ID7578042
'The Ca(2+)-ATPase of skeletal muscle sarcoplasmic reticulum is inhibited by 2,5-di-tert-butyl-1,4-dihydroxybenzene (BHQ) and other hydrophobic 1,4-dihydroxybenzenes. Inhibitory potency increases on increasing substituent chain length from 2,5-dipropyl-1,4-dihydroxybenzene to 2,5-di-tert-amyl-1,4-dihydroxybenzene, the most potent inhibitor, but then decreases for 2,5-bis(7-methylheptyl)-1,4-dihydroxybenzene. Kinetic measurements are consistent with isomerization following the initial binding of BHQ to ... More
Association of microtubules and intermediate filaments in chicken gizzard cells as detected by double immunofluorescence.
AuthorsGeiger B, Singer SJ
JournalProc Natl Acad Sci U S A
PubMed ID7001467
'By double indirect immunofluorescence, using guinea pig and rabbit antibodies to tubulin and to desmin, we have simultaneously labeled microtubules and intermediate filaments in cultured chicken embryo gizzard cells. At the resolution of the light microscope there was extensive but not complete superposition of the labeling patterns for the two ... More
Modification of tyrosine residues in dihydrofolate reductase from Lactobacillus casei.
AuthorsRosson D, Dunlap RB
JournalBiochim Biophys Acta
PubMed ID6799002
'Dihydrofolate reductase from Lactobacillus casei was inactivated by reaction with tetranitromethane and 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole. Loss of activity occurred with modification of four of the five tyrosine residues present in the enzyme. The presence of either substrate, NADPH or 7,8-dihydrofolate, as well as NADP and folate, provided extensive protection against inactivation, while ... More
Asymmetry of Escherichia coli F1-ATPase as a function of the interaction of alpha-beta subunit pairs with the gamma and epsilon subunits.
AuthorsHaughton MA, Capaldi RA
JournalJ Biol Chem
PubMed ID7657634
'The asymmetry of Escherichia coli F1-ATPase (ECF1) has been explored in chemical modification experiments involving two mutant enzyme preparations. One mutant contains a cysteine (Cys) at position 149 of the beta subunit, along with conversion of a Val to Ala at residue 198 to suppress the deleterious effect of the ... More
Quantitative analysis of Fc gamma receptors on murine spleen cell populations by using dual parameter flow cytometry.
AuthorsTitus JA, Finkelman FD, Stephany DA, Jones JF, Segal DM
JournalJ Immunol
PubMed ID6234350
'The expression of Fc gamma R on subsets of mouse spleen cells was examined by dual parameter flow microfluorometry. B cells were detected by labeling them with antibodies against sIgM, sIgD, sIgG, or I-A; essentially all B cells expressed Fc gamma R. The number of Fc gamma R per cell ... More
Kinetics of actin elongation and depolymerization at the pointed end.
AuthorsWeber A, Northrop J, Bishop MF, Ferrone FA, Mooseker MS
JournalBiochemistry
PubMed ID3607031
'We measured the rate of elongation at the pointed filament end with increasing concentrations of G-actin [J(c) function] using villin-capped actin filaments of very small (actin/villin = 3, VA3) and relatively large size (actin/villin = 18, VA18) as nuclei for elongation. The measurements were made under physiological conditions in the ... More
Sulfenic acid formation in human serum albumin by hydrogen peroxide and peroxynitrite.
AuthorsCarballal S, Radi R, Kirk MC, Barnes S, Freeman BA, Alvarez B
JournalBiochemistry
PubMed ID12924939
'Human serum albumin (HSA), the most abundant protein in plasma, has been proposed to have an antioxidant role. The main feature responsible for this property is its only thiol, Cys34, which comprises approximately 80% of the total free thiols in plasma and reacts preferentially with reactive oxygen and nitrogen species. ... More
Probing the mechanism of ATP hydrolysis on F-actin using vanadate and the structural analogs of phosphate BeF-3 and A1F-4.
AuthorsCombeau C, Carlier MF
JournalJ Biol Chem
PubMed ID3182855
'The binding of phosphate analogs to F-ADP-actin filaments and their effect on the dynamics of the polymer have been investigated. Orthovanadate binds to F-actin with the same affinity as phosphate and, at low saturation levels, stabilizes the filament structure in a Pi-like fashion; at higher concentration, it promotes destabilization of ... More
Biochemical characterization of the yeast vacuolar H(+)-ATPase.
AuthorsKane PM, Yamashiro CT, Stevens TH
JournalJ Biol Chem
PubMed ID2478556
'The yeast vacuolar proton-translocating ATPase was isolated by two different methods. A previously reported purification of the enzyme (Uchida, E., Ohsumi, Y., and Anraku, Y. (1985) J. Biol. Chem. 260, 1090-1095) was repeated. This procedure consisted of isolation of vacuoles, solubilization with the zwitterionic detergent ZW3-14, and glycerol gradient centrifugation ... More
Study of the binding environment of alpha-factor in its G protein-coupled receptor using fluorescence spectroscopy.
AuthorsDing FX, Lee BK, Hauser M, Patri R, Arshava B, Becker JM, Naider F
JournalJ Pept Res
PubMed ID12081627
'Mating in Saccharomyces cerevisiae is induced by the interaction of alpha-factor (W1H2W3L4Q5L6K7P8G9Q10P11M12Y13) with its cognate G protein-coupled receptor (Ste2p). Fifteen fluorescently labeled analogs of alpha-factor in which the 7-nitrobenz-2-oxa-1,3-diazol-4-yl (NBD) group was placed at the alphaN-terminus and in side-chains at positions 1, 3, 4, 6, 7, 12 and 13 were ... More
Functional groups at the catalytic site of BF1 adenosinetriphosphatase from Escherichia coli.
AuthorsTing LP, Wang JH
JournalBiochemistry
PubMed ID6462170
'The rates of inactivation of BF1 adenosinetriphosphatase (BF1-ATPase) from Escherichia coli by 7-chloro-4-nitro-2,1,3-benzoxadiazole, 1-fluoro-2,4-dinitrobenzene, 2,4,6-trinitrobenzenesulfonate, phenylglyoxal, and N,N''-dicyclohexylcarbodiimide have been measured in the presence and absence of various concentrations of inorganic phosphate, ADP, ATP, or magnesium ion. Dissociation equilibrium constants and rate constants for the labeling reactions have been deduced ... More
Characterization of a vacuolar pyrophosphatase in Trypanosoma brucei and its localization to acidocalcisomes.
AuthorsRodrigues CO, Scott DA, Docampo R
JournalMol Cell Biol
PubMed ID10523660
'Inorganic pyrophosphate promoted the acidification of an intracellular compartment in permeabilized procyclic trypomastigotes of Trypanosoma brucei, as measured by acridine orange uptake. The proton gradient generated by pyrophosphate was collapsed by addition of nigericin or NH(4)Cl. Pyrophosphate-driven proton translocation was stimulated by potassium ions and inhibited by KF, by the ... More
The nature of the reaction of an essential tyrosine residue of bovine heart mitochondrial ATPase with 4-chloro-7-nitrobenzofurazan and related compounds.
AuthorsSutton R, Ferguson SJ
JournalEur J Biochem
PubMed ID6235112
'Bovine heart mitochondrial ATPase is inhibited after covalent modification with 4-chloro-7-nitrobenzofuroxan. The kinetics of the reaction are indistinguishable from those for the reaction of an essential tyrosine residue of the ATPase with 4-chloro-7-nitrobenzofurazan that have been described previously [Ferguson et al. (1975) Eur. J. Biochem. 54, 117-126]. 4-Fluoro-7-nitrobenzofurazan inhibits the ... More
Actin binding to lipid-inserted alpha-actinin.
AuthorsFritz M, Zimmermann RM, Bärmann M, Gaub HE
JournalBiophys J
PubMed ID8298017
'The interaction of alpha-actinin with lipid films and actin filaments was investigated. First alpha-actinin was incorporated in lipid films at the air/water interface. Injection of alpha-actinin into the subphase of a lipid monolayer led to a significant increase of the surface pressure only for lipid films consisting of a mixture ... More
Novel application of 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole to identify cysteine sulfenic acid in the AhpC component of alkyl hydroperoxide reductase.
AuthorsEllis HR, Poole LB
JournalBiochemistry
PubMed ID9398227
'The trapping of a sulfenic acid within the fully active C165S mutant of the AhpC peroxidase protein from Salmonella typhimurium was investigated. The electrophilic reagent employed in these studies, 7-chloro-4-nitrobenz-2-oxa-1,3-diazole (NBD-Cl), has previously been used to modify thiol, amino, and tyrosine hydroxyl groups in proteins; at neutral pH only cysteinyl ... More
The ATPase activity of the alpha 3 beta 3 complex of the F1-ATPase of the thermophilic bacterium PS3 is inactivated on modification of tyrosine 307 in a single beta subunit by 7-chloro-4-nitrobenzofurazan.
AuthorsYoshida M, Allison WS
JournalJ Biol Chem
PubMed ID2137446
'The catalytically active alpha 3 beta 3 complex, assembled as described (Miwa, K., and Yoshida, M. (1989) Proc. Natl. Acad. Sci. U. S. A. 86, 6484-6487) from the isolated alpha and beta subunits of the F1-ATPase of the thermophilic bacterium PS3 (TF1), is inactivated by 7-chloro-4-nitrobenzofurazan (Nbf-Cl) with characteristics very ... More
Native talin is a dumbbell-shaped homodimer when it interacts with actin.
AuthorsGoldmann WH, Bremer A, Häner M, Aebi U, Isenberg G
JournalJ Struct Biol
PubMed ID8031639
'Electron microscopy of glycerol-sprayed and rotary metal-shadowed talin from human platelets reveals a dumbbell-shaped molecule with an average length of approximately 51 nm. Analytical ultracentrifugation of native talin yields a single molecular species with an apparent molecular mass of 412 (+/- 28.6) kDa and a sedimentation coefficient of S20w = ... More
Analysis of the interactions of actin depolymerizing factor with G- and F-actin.
AuthorsHayden SM, Miller PS, Brauweiler A, Bamburg JR
JournalBiochemistry
PubMed ID8399168
'Chick actin depolymerizing factor (ADF) is an actin binding protein previously shown to rapidly depolymerize actin filaments in vitro, yielding a 1:1 complex of ADF and actin monomer. Here we show that ADF protects actin monomer from denaturation by EDTA by inhibiting the exchange of actin-bound nucleotide. Under low ionic ... More
Purification and properties of an ATPase from Sulfolobus solfataricus.
AuthorsHochstein LI, Stan-Lotter H
JournalArch Biochem Biophys
PubMed ID1533499
'A sulfite-activated ATPase isolated from Sulfolobus solfataricus had a relative molecular mass of 370,000. It was composed of three subunits whose relative molecular masses were 63,000, 48,000, and 24,000. The enzyme was inhibited by the vacuolar ATPase inhibitors nitrate and N-ethylmaleimide; 4-chloro-7-nitrobenzofurazan (NBD-Cl) was also inhibitory. N-Ethylmaleimide was predominately bound ... More
Lateral diffusion of surface immunoglobulin, Thy-1 antigen, and a lipid probe in lymphocyte plasma membranes.
'Fluorescence photobleaching recovery was used to measure the lateral diffusion coefficient and mobile fraction of surface immunoglobulin (sIg), Thy-1 antigen, and a lipid probe in the plasma membrane of mouse lymphocytes. The lipid probe (3,3''-dioctadecylindocarbocyanine) had a mean (+/-SD) diffusion coefficient of (1.7 +/- 0.3) x 10(-8) cm(2)/sec, with essentially ... More
Location of the stilbenedisulfonate binding site of the human erythrocyte anion-exchange system by resonance energy transfer.
AuthorsRao A, Martin P, Reithmeier RA, Cantley LC
JournalBiochemistry
PubMed ID497152
'The stilbenedisulfonate inhibitory site of the human erythrocyte anion-exchange system has been characterized by using serveral fluorescent stilbenedisulfonates. The covalent inhibitor 4-benzamido-4''-isothiocyanostilbene-2,2''-disulfonate (BIDS) reacts specifically with the band 3 protein of the plasma membrane when added to intact erythrocytes, and the reversible inhibitors 4,4''-dibenzamidostilbene-2,2''-disulfonate (DBDS) and 4-benzamido-4''-aminostilbene-2,2''-disulfonate (BADS) show a ... More
Labeling of human erythrocyte membranes with eosin probes used for protein diffusion measurements: inhibition of anion transport and photo-oxidative inactivation of acetylcholinesterase.
AuthorsNigg E, Kessler M, Cherry RJ
JournalBiochim Biophys Acta
PubMed ID215229
'The binding of eosin-isothiocyanate (eosin-NCS) and iodoacetamido-eosin (IA-eosin) to band 3 proteins in the membrane of human erythrocytes is characterized by studying the effect of these probes on the anion transport system. Although the unbrominated fluorescein precursors do not affect anion transport, both eosin labels are strong inhibitors of sulphate ... More
ATP-dependent spectral response of oxonol VI in an ATP-Pi exchange complex.
AuthorsKiehl R, Hanstein WG
JournalBiochim Biophys Acta
PubMed ID6235853
'Energy transduction in an ATPase complex (complex V) has been studied in two reactions catalyzed by this system, i.e., ATP-dependent spectral shift of oxonol VI, and ATP-Pi exchange activity. Aurovertin alone inhibits 50% of the oxonol shift at 2 microM, and no further inhibition occurs at up to 12 microM. ... More
Lipid-modified, cysteinyl-containing peptides of diverse structures are efficiently S-acylated at the plasma membrane of mammalian cells.
AuthorsSchroeder H, Leventis R, Shahinian S, Walton PA, Silvius JR
JournalJ Cell Biol
PubMed ID8707845
'A variety of cysteine-containing, lipid-modified peptides are found to be S-acylated by cultured mammalian cells. The acylation reaction is highly specific for cysteinyl over serinyl residues and for lipid-modified peptides over hydrophilic peptides. The S-acylation process appears by various criteria to be enzymatic and resembles the S-acylation of plasma membrane-associated ... More
Inhibition of Na+-dependent phosphate transport by group-specific covalent reagents in rat kidney brush border membrane vesicles. Evidence for the involvement of tyrosine and sulfhydryl groups on the interior of the membrane.
AuthorsPratt RD, Pedersen PL
JournalArch Biochem Biophys
PubMed ID2912384
'The effects of tyrosine- and sulfhydryl-specific reagents on the Na+-dependent transport of phosphate in brush border membrane vesicles prepared from rat renal cortex were investigated. This study is the first to show that the tyrosine-specific reagents 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole and tetranitromethane inactivate the transporter in a concentration- and time-dependent fashion while the ... More
Similarity of lysosomal H+-ATPase to mitochondrial F0F1-ATPase in sensitivity to anions and drugs as revealed by solubilization and reconstitution.
AuthorsMoriyama Y, Takano T, Ohkuma S
JournalBiochim Biophys Acta
PubMed ID2867782
'Lysosomal H+-translocating ATPase (H+-ATPase) was solubilized with lysophosphatidylcholine and reconstituted into liposomes (Moriyama, Y., Takano, T. and Ohkuma, S. (1984) J. Biochem. (Tokyo) 96, 927-930). In this study, the sensitivities of membrane-bound, solubilized and liposome-incorporated ATPase to various anions and drugs were measured in comparison with those of similar forms ... More
Reaction of membrane-bound F1-adenosine triphosphatase of Escherichia coli with chemical ligands and the asymmetry of beta subunits.
AuthorsBragg PD, Hou C
JournalBiochim Biophys Acta
PubMed ID2137013
'The three beta subunits of the isolated Escherichia coli F1-ATPase react independently with chemical reagents (Stan-Lotter, H. and Bragg, P.D. (1986) Arch. Biochem. Biophys. 284, 116-120). Thus, one beta subunit is readily cross-linked to the epsilon subunit, Another reacts with N,N''-dicyclohexylcarbodiimide (DCCD), and the third one is modified on a ... More
Site-directed mutagenesis of the yeast V-ATPase A subunit.
AuthorsLiu Q, Leng XH, Newman PR, Vasilyeva E, Kane PM, Forgac M
JournalJ Biol Chem
PubMed ID9115229
'To investigate the function of residues at the catalytic nucleotide binding site of the V-ATPase, we have carried out site-directed mutagenesis of the VMA1 gene encoding the A subunit of the V-ATPase in yeast. Of the three cysteine residues that are conserved in all A subunits sequenced thus far, two ... More
Roles of superoxide radical anion in signal transduction mediated by reversible regulation of protein-tyrosine phosphatase 1B.
'Growth factors induce intracellular production of reactive oxygen species in non-phagocytic cells and elevation of their phosphorylated protein tyrosine level. The latter can be achieved by activating protein-tyrosine kinases and/or inactivating protein-tyrosine phosphatases (PTPs). A highly abundant PTP, PTP-1B, is known to be inactivated by oxidation of its catalytic site ... More
Thioredoxin-dependent hydroperoxide peroxidase activity of bacterioferritin comigratory protein (BCP) as a new member of the thiol-specific antioxidant protein (TSA)/Alkyl hydroperoxide peroxidase C (AhpC) family.
AuthorsJeong W, Cha MK, Kim IH
JournalJ Biol Chem
PubMed ID10644761
'Escherichia coli bacterioferritin comigratory protein (BCP), a putative bacterial member of the TSA/AhpC family, was characterized as a thiol peroxidase. BCP showed a thioredoxin-dependent thiol peroxidase activity. BCP preferentially reduced linoleic acid hydroperoxide rather than H(2)O(2) and t-butyl hydroperoxide with the use of thioredoxin as an in vivo immediate electron ... More
Mitochondrial ATP synthase. Overexpression in Escherichia coli of a rat liver beta subunit peptide and its interaction with adenine nucleotides.
AuthorsGarboczi DN, Hullihen JH, Pedersen PL
JournalJ Biol Chem
PubMed ID2902092
'The C-terminal two-thirds of the rat liver ATP synthase beta subunit has been overexpressed and exported to the Escherichia coli periplasm under the direction of the alkaline phosphatase (phoA) promoter and leader peptide. The processed soluble protein contains the 358 amino acids from glutamate 122 to the rat liver beta ... More
Protection by alcuronium of muscarinic receptors against chemical inactivation and location of the allosteric binding site for alcuronium.
AuthorsJakubík J, Tucek S
JournalJ Neurochem
PubMed ID7931349
'We have found earlier that the neuromuscular blocker alcuronium binds to cardiac muscarinic receptors simultaneously with their specific antagonist [3H]methyl-N-scopolamine ([3H]NMS) and allosterically increases their affinity to this ligand. Nothing is known about the allosteric site with which alcuronium interacts. To gain an insight, we have now investigated how the ... More
Parallel analysis with optically gated sample introduction on a multichannel microchip.
AuthorsXu H, Roddy TP, Lapos JA, Ewing AG
JournalAnal Chem
PubMed ID12433082
'As an alternative to the T-type injection on microchips, optically gated sample introduction previously has been demonstrated to provide fast, serial, and reproducible injections on a single-channel microchip. Here, the ability to perform high throughput, multichannel analysis with optically gated sample introduction is described using a voice coil actuator. The ... More
Inhibitory properties of a novel human Kunitz-type protease inhibitor homologous to tissue factor pathway inhibitor.
AuthorsPetersen LC, Sprecher CA, Foster DC, Blumberg H, Hamamoto T, Kisiel W
JournalBiochemistry
PubMed ID8555184
'In a previous report, we described the molecular cloning, expression, and partial characterization of a second human tissue factor pathway inhibitor (TFPI), which we designated as TFPI-2 [Sprecher, C. A., et al. (1994) Proc. Natl. Acad. Sci. U.S.A. 91, 3353-3357]. Recombinant TFPI-2 inhibited the amidolytic activity of trypsin as well ... More
Calcium-stimulated protein phosphorylation in synaptic membranes.
AuthorsSorensen RG, Mahler HR
JournalJ Neurochem
PubMed ID6550623
'Synaptic membranes from rat brain contain several calcium-requiring protein kinase (PK) activities with different substrate specificities: (a) an activity (CaH-PK) effective at high concentrations of Ca2+ ion in the absence of Mg2+ (active on class F substrates); (b) a (Ca + Mg)-PK activity that is mediated by Ca2+ ion in ... More
Synthesis and pharmacological activity of fluorescent histamine H1 receptor antagonists related to mepyramine.
AuthorsLi L, Kracht J, Peng S, Bernhardt G, Buschauer A
JournalBioorg Med Chem Lett
PubMed ID12657255
'Fluorescently labeled histamine H(1) receptor antagonists were synthesized starting from N-demethylmepyramine by introduction of omega-aminoalkyl chains (2-8 methylene groups in length) followed by derivatization of the terminal NH(2) group with various fluorophores (fluorescein, naphthofluorescein, rhodamine, tetramethylrhodamine, BODIPY, dansyl, and nitrobenzoxadiazole (NBD)). On the isolated guinea pig ileum and in a ... More
Determination of total hydroxyproline and proline in human serum and urine by HPLC with fluorescence detection.
AuthorsInoue H, Date Y, Kohashi K, Yoshitomi H, Tsuruta Y
JournalBiol Pharm Bull
PubMed ID8850299
'A method to measure total hydroxyproline (Hyp) and proline (Pro) in human serum and urine by HPLC was developed. Hyp and Pro in acid hydrolysates of serum and urine were derivatized with 4-(5,6-dimethoxy-2-phthalimidinyl)phenysulfonyl chloride after treatment with o-phthaladehyde and cleanup on Bond Elut C18 column. The derivatives of imino acids ... More
Kinetics of myosin subfragment-1-induced condensation of G-actin into oligomers, precursors in the assembly of F-actin-S1. Role of the tightly bound metal ion and ATP hydrolysis.
AuthorsFievez S, Pantaloni D, Carlier MF
JournalBiochemistry
PubMed ID9305975
'In a low ionic strength buffer and in the absence of free ATP, the interaction of G-actin (G) with myosin subfragment-1 (S1) leads to the formation of arrowhead-decorated F-actin-S1 filaments, through a series of elementary steps. The initial formation of GS and G2S complexes is followed by their condensation into ... More
Human recombinant resistin protein displays a tendency to aggregate by forming intermolecular disulfide linkages.
'Resistin, a small cysteine rich protein secreted by adipocytes, has been proposed to be a link between obesity and type II diabetes by modulating the insulin signaling pathway and thus inducing insulin resistance. Resistin protein, with 11 cysteine residues, was not significantly homologous at the amino acid level to any ... More
Fluorescent derivatives of bile salts. II. Suitability of NBD-amino derivatives of bile salts for the study of biological transport.
AuthorsSchramm U, Dietrich A, Schneider S, Buscher HP, Gerok W, Kurz G
JournalJ Lipid Res
PubMed ID1770296
'Interaction of unconjugated and taurine-conjugated NBD-amino-dihydroxy-5 beta-cholan-24-oic acids bearing the fluorophor in the 3 alpha, 3 beta, 7 alpha, 7 beta, 12 alpha, or 12 beta position with albumin results in a small hypsochromic shift of the emission maximum and an increase in quantum yield, suggesting binding by hydrophobic interactions. ... More
Conserved cysteine residues of histidinol dehydrogenase are not involved in catalysis. Novel chemistry required for enzymatic aldehyde oxidation.
AuthorsTeng H, Segura E, Grubmeyer C
JournalJ Biol Chem
PubMed ID8314784
'The 4-electron oxidoreductase L-histidinol dehydrogenase (HDH, EC 1.1.1.23) oxidizes the amino alcohol histidinol to histidine via an aldehyde-level intermediate at a single active site. The enzyme contains two Zn2+ per dimer, and treatment with metal chelators causes a metal-reversible inactivation. NAD-linked aldehyde oxidations, for which glyceraldehyde-3-phosphate dehydrogenase has served as ... More
Reaction of thiol groups of gizzard myosin heavy chains with 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole.
AuthorsBailin G, Shah T, Huang JR
JournalArch Biochem Biophys
PubMed ID2143367
'Chicken gizzard myosin treated with 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole (NBD-Cl) resulted in a 65% inhibition of the K(+)-ATPase (myosin ATP phosphohydrolase (actin translocating), EC 3.6.1.32) activity and 3.5 mol of the reagent was bound per 4.7 x 10(5) g protein. The labeling was limited to the heavy chain region and none of the ... More
Synthesis and pharmacological activity of fluorescent histamine H2 receptor antagonists related to potentidine.
'Fluorescently labeled histamine H(2) receptor antagonists were synthesized starting from N-cyano-N''-[3-(3-piperidin-1-ylmethylphenoxy)propyl]guanidines with an additional N"-omega-aminoalkyl substituent (chain lengths 2-8 methylene groups) or from 3-(3-piperidin-1-ylmethylphenoxy)propylamine. The primary amino group was derivatized with various fluorophores (fluorescein, acridine, dansyl, nitrobenzoxadiazole (NBD), indolo[2,3-a]quinolizine). On the isolated spontaneously beating guinea pig right atrium most of ... More
Filament assembly from profilin-actin.
AuthorsGutsche-Perelroizen I, Lepault J, Ott A, Carlier MF
JournalJ Biol Chem
PubMed ID10037710
'Profilin plays a major role in the assembly of actin filament at the barbed ends. The thermodynamic and kinetic parameters for barbed end assembly from profilin-actin have been measured turbidimetrically. Filament growth from profilin-actin requires MgATP to be bound to actin. No assembly is observed from profilin-CaATP-actin. The rate constant ... More
Azide as a probe of co-operative interactions in the mitochondrial F1-ATPase.
AuthorsHarris DA
JournalBiochim Biophys Acta
PubMed ID2523739
'(1) The hydrolytic activity of the isolated mitochondrial ATPase (F1) is strongly inhibited by azide. However, at very low ATP concentration (1 microM or less), no inhibition by azide is observed. (2) The azide-insensitive ATPase activity represents a high-affinity, low-capacity mode of turnover of F1. This is identified with the ... More
Inhibition of the human sodium/bile acid cotransporters by side-specific methanethiosulfonate sulfhydryl reagents: substrate-controlled accessibility of site of inactivation.
AuthorsHallén S, Fryklund J, Sachs G
JournalBiochemistry
PubMed ID10828993
'Mammalian sodium/bile acid cotransporters (SBATs) constitute a subgroup of the sodium cotransporter superfamily and function in the enterohepatic circulation of bile acids. They are glycoproteins with an exoplasmic N-terminus, seven or nine transmembrane segments, and a cytoplasmic C-terminus. They exhibit no significant homology with other members of the sodium cotransporter ... More
Kinetic analysis of the interaction of actin-depolymerizing factor (ADF)/cofilin with G- and F-actins. Comparison of plant and human ADFs and effect of phosphorylation.
AuthorsRessad F, Didry D, Xia GX, Hong Y, Chua NH, Pantaloni D, Carlier MF
JournalJ Biol Chem
PubMed ID9694836
'The thermodynamics and kinetics of actin interaction with Arabidopsis thaliana actin-depolymerizing factor (ADF)1, human ADF, and S6D mutant ADF1 protein mimicking phosphorylated (inactive) ADF are examined comparatively. ADFs interact with ADP.G-actin in rapid equilibrium (k+ = 155 microM-1.s-1 and k- = 16 s-1 at 4 degreesC under physiological ionic conditions). ... More
Mechanism of myosin subfragment-1-induced assembly of CaG-actin and MgG-actin into F-actin-S1-decorated filaments.
AuthorsFievez S, Carlier MF, Pantaloni D
JournalBiochemistry
PubMed ID9305976
'The kinetics and mechanism of myosin subfragment-1-induced polymerization of G-actin into F-actin-S1-decorated filaments have been investigated in low ionic strength buffer and in the absence of free ATP. The mechanism of assembly of F-actin-S1 differs from salt-induced assembly of F-actin. Initial condensation of G-actin and S1 into oligomers in reversible ... More
Ligand-induced changes in the accessibility of sulphydryl groups of Neurospora crassa pyruvate kinase.
AuthorsKapoor M, Parfett CL
JournalInt J Biochem
PubMed ID154420
Simultaneous use of contrasting fluorochromes to separate measles and canine distemper viruses in a common system.
AuthorsGourlay JA, Pemberton JR
JournalAppl Microbiol
PubMed ID5000868
'Measles and canine distemper viruses were grown together in a Vero monkey kidney cell line. Each virus could be identified and individually titrated by using the color contrast produced by the reddish tetra-methyl rhodamine isothiocyanate-tagged antimeasles conjugate and the green fluorescein isothiocyanate-tagged antidistemper conjugate. Both blue light and green light ... More
Cytosolic pH regulation in mouse macrophages. Proton extrusion by plasma-membrane-localized H(+)-ATPase.
AuthorsTapper H, Sundler R
JournalBiochem J
PubMed ID1531009
'Recent evidence indicates that H+ extrusion in macrophages is in part accomplished by a H(+)-ATPase of vacuolar type. The presence and plasma-membrane localization of such a mechanism in adherent resident macrophages was verified by inhibition of H+ extrusion, monitored by changes in both cytosolic pH (pHi) and extracellular pH, with ... More
Fluorophoric assay for the high-throughput determination of amidase activity.
AuthorsHenke E, Bornscheuer UT
JournalAnal Chem
PubMed ID12553759
'An assay has been developed for the high-throughput identification of amidase activity. Amines released from the enzyme-catalyzed hydrolysis of corresponding amides were detected by the formation of a fluorescent dye by coupling with 4-nitro-7-chloro-benzo-2-oxa-1,3-diazole (NBD-CI). Using this format, 22 lipases and esterases were tested for their ability to hydrolyze aromatic ... More
Specificity of association of a Ca2+/Mg2+ ATPase with cholinergic synaptic vesicles from Torpedo electric organ.
AuthorsRothlein JE, Parsons SM
JournalBiochem Biophys Res Commun
PubMed ID157132
Chemical modification of the beta-subunit isolated from a membrane-bound Fo-F1-ATP synthase: modification by 4-chloro-7-nitrobenzofurazan does not inhibit restoration of ATP synthesis or hydrolysis.
AuthorsKhananshvili D, Gromet-Elhanan Z
JournalBiochem Biophys Res Commun
PubMed ID6184056
Lateral diffusion of a hydrophobic peptide, N-4-nitrobenz-2-oxa-1,3-diazole gramicidin S, in phospholipid multibilayers.
AuthorsWu ES, Jacobson K, Szoka F, Portis A
JournalBiochemistry
PubMed ID83159
Investigation on the interactions of peptides in the assembly of liposome and peptide by fluorescence.
AuthorsUemura A, Kimura S, Imanishi Y
JournalBiochim Biophys Acta
PubMed ID6830785
'The peptide-lipid and the peptide-peptide interactions of hydrophobic linear dipeptides containing tryptophan in liposome were investigated by fluorescence. The linear dipeptides were buried into the hydrophobic region of liposome to induce blue-shift of the fluorescence. With the addition of various anthracene derivatives to liposome, the energy transfer from tryptophan to ... More
The synthesis and use of fluorescent oligonucleotides in DNA sequence analysis.
AuthorsSmith LM, Kaiser RJ, Sanders JZ, Hood LE
JournalMethods Enzymol
PubMed ID3431463
2,4,6-Trinitrobenzenesulfonate labels an essential amino group near the bound phosphate at the catalytic site of mitochondrial F1-ATPase.
AuthorsTing LP, Wang JH
JournalBiochem Biophys Res Commun
PubMed ID6458293
Intramolecular distances within the Ca(2+)-ATPase from sarcoplasmic reticulum as estimated through fluorescence energy transfer between probes.
'Fluorescence energy transfer measurements have been carried out to estimate intramolecular distances between probes bound to Ca(2+)-transporting ATPase (Ca(2+)-ATPase) as well as distances between these probes and the phospholipid headgroup. The nucleotide binding site was monitored by using 1,N6-ethenoadenosine 5''-triphosphate, a fluorescent analogue of ATP, and also by labelling Lys515 ... More
The Escherichia coli F1-ATPase mutant beta Tyr-297-->Cys: functional studies and asymmetry of the enzyme under various nucleotide conditions based on reaction of the introduced Cys with N-ethylmaleimide and 7-chloro-4-nitrobenzofurazan.
AuthorsHaughton MA, Capaldi RA
JournalBiochim Biophys Acta
PubMed ID8816947
'Conversion of residue beta Tyr-297 of the Escherichia coli F1-ATPase (ECF1) to a Cys in the mutant beta Y297C led to impaired oxidative phosphorylation based on growth curves. The ATPase activity of ECF1 isolated from the mutant beta Y297C was only 1% of wild-type activity, but the residual activity involves ... More
Identification of the essential tyrosine residue in the beta subunit of bovine heart mitochondrial F1-ATPase that is modified by 7-chloro-4-nitro[14C]benzofurazan.
AuthorsAndrews WW, Hill FC, Allison WS
JournalJ Biol Chem
PubMed ID6234310
'Inactivation of the bovine heart mitochondrial F1-ATPase, taken as alpha 3 beta 3 gamma delta epsilon with a molecular weight of 375,000, with a 4-fold molar excess of 7-chloro-4-nitro[14C]benzofurazan at pH 7.5, led to the incorporation of 1.42 g atoms of 14C/mol. Treatment of the inactivated enzyme with dithiothreitol removed ... More
A fluorescent assay for the determination of UDP-GlcNAc: Gal beta 1,3GalNAc-R (GlcNAc to GalNAc) beta 1,6-N-acetylglucosaminyltransferase activity.
AuthorsPalmerini CA, Datti A, Alunni S, VanderElst IE, Orlacchio A
JournalAnal Biochem
PubMed ID7762797
'A fluorescent assay for UDP-GlcNAc: Gal beta 1,3Gal-NAc-R beta 1,6-N-acetylglucosaminyltransferase (core 2 GlcNAc-T) activity has been developed involving dansylation of the enzyme reaction product. Core 2 GlcNAc-T detection was performed using unlabeled UDP-GlcNAc as the donor and Gal beta 1,3GalNAc alpha-pAp as the acceptor. The product, Gal beta 1,3(GlcNAc beta ... More
The cell adhesion molecule DdCAD-1 in Dictyostelium is targeted to the cell surface by a nonclassical transport pathway involving contractile vacuoles.
AuthorsSesaki H, Wong EF, Siu CH
JournalJ Cell Biol
PubMed ID9265658
'DdCAD-1 is a 24-kD Ca2+-dependent cell- cell adhesion molecule that is expressed soon after the initiation of development in Dictyostelium cells. DdCAD-1 is present on the cell surface as well as in the cytosol. However, the deduced amino acid sequence of DdCAD-1 lacks a hydrophobic signal peptide or any predicted ... More
Calcium dependence of villin-induced actin depolymerization.
AuthorsWalsh TP, Weber A, Davis K, Bonder E, Mooseker M
JournalBiochemistry
PubMed ID6525347
'"Cutting" of actin filaments by villin was evaluated from the time course of filament depolymerization. Depolymerization was initiated by diluting polymerized actin, labeled with a fluorescent probe on either lysine-374 or cysteine-375, to a concentration well below the critical into a medium containing free villin and various concentrations of calcium ... More
AuthorsDreyfuss G, Schwartz K, Blout ER, Barrio JR, Liu FT, Leonard NJ
JournalProc Natl Acad Sci U S A
PubMed ID206888
'An approach to the study of protein receptor sites in protein mixtures or supramolecular assemblies by using fluorescence spectroscopy is described. This approach, fluorescent photoaffinity labeling, combines the merits of photoaffinity labeling to attain site-directed reactivity with the probing power of fluorescent ligands. A fluorescent photoaffinity label for cyclic AMP ... More
Flow cytofluorometric analysis of insulin binding and internalization by Swiss 3T3 cells.
AuthorsMurphy RF, Powers S, Verderame M, Cantor CR, Pollack R
JournalCytometry
PubMed ID6804197
'The binding of a fluorescein-isothiocyanate derivative of insulin to Swiss 3T3 cells was measured by flow cytometry. The kinetics of the subsequent internalization were also measured; at a concentration of 1 microM labeled insulin approximately 25% of the internalization was insulin-specific. The kinetics of endocytosis were contrasted to those of ... More
A solid sorbent air sampling and analytical procedure for methyl-, dimethyl-, ethyl-, and diethylamine.
AuthorsElskamp CJ, Schultz GR
JournalAm Ind Hyg Assoc J
PubMed ID3946199
'A sampling and analytical procedure for methyl-, dimethyl-, ethyl-, and diethylamine was developed in order to avoid problems typically encountered in the sampling and analysis of low molecular weight aliphatic amines. Samples are collected with adsorbent tubes containing Amberlite XAD-7 resin coated with the derivatizing reagent, NBD chloride (7-chloro-4-nitrobenzo-2-oxa-1,3-diazole). Analysis ... More
Determination of collagen and protein turnover by high-performance liquid chromatography.
AuthorsStratford MR, Watfa RR, Murray JC, Martin SG
JournalJ Chromatogr
PubMed ID2361981
'A high-performance liquid chromatographic method is described for the determination of tissue collagen and protein synthesis rates in vivo, together with an index of collagen degradation. The technique utilises post-column reaction with 7-chloro-4-nitrobenzofurazan (NBDCl), which shows higher reactivity towards the secondary amino acids, proline and hydroxyproline, and also exploits differences ... More
Fluorescent peptide probes for high-throughput measurement of protein phosphatases.
AuthorsNoble JE, Ganju P, Cass AE
JournalAnal Chem
PubMed ID12720338
'A homogeneous microplate assay for the serine/threonine protein phosphatases PP1 and PP2A, employing fluorescent-labeled phosphopeptides, has been developed. Phosphopeptides derived from a phosphoacceptor site in myelin basic protein were designed with a cysteine adjacent to the phosphoresidue, allowing site-selective labeling with dyes. The fluorescence emission from the environmentally sensitive fluorophore ... More
20 S proteasome from Saccharomyces cerevisiae is responsive to redox modifications and is S-glutathionylated.
AuthorsDemasi M, Silva GM, Netto LE
JournalJ Biol Chem
PubMed ID12409293
'The 20 S proteasome core purified from Saccharomyces cerevisiae is inhibited by reduced glutathione (GSH), cysteine (Cys), or the GSH precursor gamma-glutamylcysteine. Chymotrypsin-like activity was more affected by GSH than trypsin-like activity, whereas the peptidylglutamyl-hydrolyzing activity (caspase-like) was not inhibited by GSH. Cys-sulfenic acid formation in the 20 S core ... More
The ATP-binding site of the human placental H+ pump contains essential tyrosyl residues.
AuthorsKulanthaivel P, Simon BJ, Burckhardt G, Mahesh VB, Leibach FH, Ganapathy V
JournalBiochemistry
PubMed ID2148692
'Transient exposure of human placental brush-border membrane vesicles to cholate reorients the ATP-driven H+ pump, enabling the pump to transport H+ into the vesicles upon addition of ATP to the external medium. H+ uptake can be measured in these vesicles by following the decrease in the absorbance of acridine orange, ... More
Interactions between transport inhibitors at the anion binding sites of the band 3 dimer.
AuthorsMacara IG, Cantley LC
JournalBiochemistry
PubMed ID7295667
'Evidence is presented that the binding of aromatic disulfonates to the external transport sites of the red cell anion-exchange protein (band 3) can exhibit negative cooperativity. Fluorescence resonance energy transfer has been used to compare the affinities of an aromatic disulfonate 4,4'-bis-(4-nitro-2,1,3-benzoxadiazolyl)dihydrostilbene-2,2'-disulfonate[H2(NBD)2DS] for "empty" band 3 dimers (in which neither ... More
Effect of villin on the kinetics of actin polymerization.
AuthorsWalsh TP, Weber A, Higgins J, Bonder EM, Mooseker MS
JournalBiochemistry
PubMed ID6432033
'The effect of villin on the critical concentration of actin and on the kinetics of its polymerization has been measured. In the presence of villin and 10 microM calcium, the critical concentration of actin increased from 0.2 to 0.9 microM. This effect of villin on the critical concentration was shown ... More
Translocation of molecules into cells by pH-dependent insertion of a transmembrane helix.
AuthorsReshetnyak YK, Andreev OA, Lehnert U, Engelman DM
JournalProc Natl Acad Sci U S A
PubMed ID16608910
'We have previously observed the spontaneous, pH-dependent insertion of a water-soluble peptide to form a helix across lipid bilayers [Hunt, J. F., Rath, P., Rothschild, K. J. & Engelman, D. M. (1997) Biochemistry 36, 15177-15192]. We now use a related peptide, pH (low) insertion peptide, to translocate cargo molecules attached ... More
Characterization of oligomers as kinetic intermediates in myosin subfragment 1-induced polymerization of G-actin.
AuthorsValentin-Ranc C, Carlier MF
JournalJ Biol Chem
PubMed ID1400465
'The nature of the kinetic intermediates involved in S1-induced polymerization of G-actin into F-acto-S1-decorated filaments has been investigated using as probes light scattering, the fluorescence of pyrenyl- or NBD-labeled actin, and the anisotropy of fluorescence of N-iodoacetyl-N''-(5-sulfo-1-napthyl)ethylene diamine (AEDANS)-labeled actin. With AEDANS-G-actin, the initial formation of a ternary G2S complex ... More
Cytotoxicity and apoptosis produced by arachidonic acid in Hep G2 cells overexpressing human cytochrome P4502E1.
AuthorsChen Q, Galleano M, Cederbaum AI
JournalJ Biol Chem
PubMed ID9169410
'The goal of the current study was to evaluate the effects of arachidonic acid, as a representative polyunsaturated fatty acid, on the viability of a Hep G2 cell line, which has been transduced to express human cytochrome P4502E1 (CYP2E1). Arachidonic acid produced a concentration- and time-dependent toxicity to Hep G2-MV2E1-9 ... More
The interaction of 4-chloro-7-nitrobenzofurazan with Rhodospirillum rubrum chromatophores, their soluble F1-ATPase, and the isolated purified beta-subunit.
AuthorsKhananshvili D, Gromet-Elhanan Z
JournalJ Biol Chem
PubMed ID6219996
'ATP synthesis and hydrolysis by Rhodospirillum rubrum chromatophores as well as the soluble RrF1-ATPase activity are inhibited by 4-chloro-7-nitrobenzofurazan (NBD-C1) in a dithiothreitol-reversible manner. Using the method earlier developed in these chromatophores to remove specifically the beta-subunit from their membrane-bound RrF1 leaving all other subunits attached to the resulting inactive ... More
Cytosolic pH regulation in chicken enterocytes: Na(+)-independent regulatory cell alkalinization.
AuthorsPeral MJ, Calonge ML, Ilundáin AA
JournalBiochim Biophys Acta
PubMed ID7530492
'The mechanisms involved in intracellular pH (pHi) recovery from an acid load have been investigated in enterocytes isolated from chicken. Following an intracellular acidification, by abrupt withdrawal of NH4Cl, pHi alkalinized in the nominally absence of Na+ and bicarbonate. This Na(+)- and bicarbonate-independent (NBI) regulatory cell alkalinization became negligible when ... More
New reaction of 4-chloro-7-nitrobenzofurazan with amines at high local concentrations. Primitive enzyme models.
AuthorsBello J, Patrzyc H
JournalInt J Pept Protein Res
PubMed ID7440055
'The fluorogenic amine reagent 4-chloro-7-nitrobenzofurazan (CNBFz) reacts with amines to give one of two products, or a mixture, depending on the concentration of amine. At low concentrations (e.g. 5 X 10(-4) M) of unprotonated amine the normal replacement of the chlorine occurs, giving lambdamax approximately 470 nm. At high concentration ... More
Structural mapping of rabbit muscle phosphofructokinase. Distance between the adenosine cyclic 3',5'-phosphate binding site and a reactive sulfhydryl group.
AuthorsCraig DW, Hammes GG
JournalBiochemistry
PubMed ID6243478
'The cAMP binding site of rabbit muscle phosphofructokinase has been labeled with the fluorescent molecule 5''-(p-fluorosulfonylbenzoyl)-2-aza-1,N6-ethenoadenosine. The most reactive sulfhydry- group of this modified enzyme, which is catalytically active, has been labeled with 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole and with N-]4-(dimethylamino)-3,5-dinitrophenyl]maleimide. The calculated distances between the cAMP binding site and the most reactive sulfhydryl ... More
Conformational interactions between alpha and beta subunits in the F1 ATPase of Escherichia coli as shown by chemical modification of uncA401 and uncD412 mutant enzymes.
AuthorsStan-Lotter H, Bragg PD
JournalEur J Biochem
PubMed ID2876891
'In contrast to wild-type F1 adenosine triphosphatase, the beta subunits of soluble ATPase from Escherichia coli mutant strains AN120 (uncA401) and AN939 (uncD412) were not labeled by the fluorescent thiol-specific reagents 5-iodoacetamidofluorescein, 2-(4''-iodoacetamidoanilino)naphthalene-6-sulfonic acid or 4-[N-(iodoacetoxy)ethyl-N-methyl]amino-7-nitrobenzo-2-oxa-1,3-diazole. The mutation in the alpha subunit (uncA401) of F1 ATPase thus influences the accessibility ... More
High Brønsted beta nuc values in SNAr displacement. An indicator of the SET pathway?
AuthorsTerrier F, Mokhtari M, Goumont R, Hallé JC, Buncel E
JournalOrg Biomol Chem
PubMed ID12926366
'Nucleophilic substitutions of 4-chloro-7-nitrobenzofurazan (NBD-Cl) and 3-methyl-1-(4-nitrobenzofurazanyl)-imidazolium ions (NBD-Im+) with a series of 4-X-substituted anilines have been kinetically investigated in 70-30 (v/v) and 20-80 (v/v) H2O-Me2SO mixtures. The rate-limiting step in these reactions is nucleophilic addition with formation of Meisenheimer-type sigma-adducts followed by fast expulsion of the leaving group (Cl- ... More
N-acetylimidazole inactivates renal Na,K-ATPase by disrupting ATP binding to the catalytic site.
AuthorsArgüello JM, Kaplan JH
JournalBiochemistry
PubMed ID2166561
'Treatment of renal Na,K-ATPase with N-acetylimidazole (NAI) results in loss of Na,K-ATPase activity. The inactivation kinetics can be described by a model in which two classes of sites are acetylated by NAI. The class I sites are rapidly reacting, the acetylation is prevented by the presence of ATP (K0.5 congruent ... More
The rational design of allosteric interactions in a monomeric protein and its applications to the construction of biosensors.
'Rational protein design is an emerging approach for testing general theories of structure and function. The ability to manipulate function rationally also offers the possibility of creating new proteins of biotechnological value. Here we use the design approach to test the current understanding of the structural principles of allosteric interactions ... More
Nucleation of actin polymerization by villin and elongation at subcritical monomer concentration.
AuthorsWeber A, Northrop J, Bishop MF, Ferrone FA, Mooseker MS
JournalBiochemistry
PubMed ID3607030
'We have obtained a quantitative description of villin-nucleated actin polymerization in physiological salt by determining the concentrations of free villin (V), villin-actin monomer (VA), villin-actin dimer (VA2), and villin-actin oligomer (VAn). Over a range of actin-villin ratios from 0.1 to 20 we determined the concentration of actin-bound villin by measuring ... More
Selective arylation of cysteine-237 of rabbit muscle aldolase with 4-chloro-7-nitrobenzofurazan.
AuthorsWong P, Harper ET
JournalBiochim Biophys Acta
PubMed ID7055573
'At pH 7.0 and 25 degrees C, NBF-Cl (4-chloro-7-nitrobenzofurazan) reacts rapidly with rabbit muscle aldolase (D-fructose-1,6-bisphosphate D-glyceraldehyde-3-phosphate-lyase, EC 4.1.2.13) to yield a product with an absorption maximum at 402 nm, which is shifted to 422 nm upon acid denaturation. The reaction involves arylation of a single cysteine residue per subunit ... More
Agglutination of isolated rod outer segments by lectins.
AuthorsBridges CD
JournalInvest Ophthalmol Vis Sci
PubMed ID6969711
'The interactions of ten lectins with rod outer segment (ROS) plasma membranes and the effects of various haptene sugars were examined by studying agglutination in suspensions of washed ROSs. It is concluded that agglutination sites on the ROS membrane involve receptors that are recognized by eight lectins with haptene sugar ... More
Characterization of the ATP-dependent proton pump of clathrin-coated vesicles.
AuthorsForgac M, Cantley L
JournalJ Biol Chem
PubMed ID6145711
'The ATP-dependent proton pump which was previously identified in clathrin-coated vesicles isolated from calf brain (Forgac, M., Cantley, L., Wiedenmann, B., Altstiel, L., and Branton, D. (1983) Proc. Natl. Acad. Sci. U.S.A. 80, 1300-1303) is further characterized. 7-Chloro-4-nitrobenz-2-oxa-1,3-diazole (NBD-Cl) was identified as a potent inhibitor of both ATP-dependent proton uptake ... More