AuthorsKotaniguchi H, Kawakatsu M, Toyo'oka T, Imai K
JournalJ Chromatogr
PubMed ID3667816
Determination of D-alanine in the rat central nervous system and periphery using column-switching high-performance liquid chromatography.
AuthorsMorikawa A, Hamase K, Zaitsu K
JournalAnal Biochem
PubMed ID12479836
'A column-switching chiral HPLC system for the determination of minute amounts of D-Ala in mammalian tissues has been established. D-Ala and its L-enantiomer are purified as a DL mixture on a micro-ODS column after precolumn fluorescence derivatization with 4-fluoro-7-nitro-2,1,3-benzoxadiazole and are introduced to a chiral column to determine each enantiomer. ... More
Derivatization in capillary electrophoresis.
AuthorsBardelmeijer HA, Lingeman H, de Ruiter C, Underberg WJ
JournalJ Chromatogr A
PubMed ID9646486
'In recent years capillary electrophoresis (CE) has been developed into a versatile separation technique, next to gas and liquid chromatography (LC), well suited for the determination of a wide variety of e.g., pharmaceutical, biomedical and environmental samples. The main advantages of CE over chromatographic separation techniques are its simplicity and ... More
The structure and organization of synthetic putative membranous segments of ROMK1 channel in phospholipid membranes.
AuthorsBen-Efraim I, Shai Y
JournalBiophys J
PubMed ID8994595
'The hydropathy plot of ROMK1, an inwardly rectifying K+ channel, suggests that the channel contains two transmembrane domains (M1 and M2) and a linker between them with significant homology to the H5 pore region of voltage-gated K+ channels. To gain structural information on the pore region of the ROMK1 channel, ... More
Structural characterization, membrane interaction, and specific assembly within phospholipid membranes of hydrophobic segments from Bacillus thuringiensis var. israelensis cytolytic toxin.
AuthorsGazit E, Shai Y
JournalBiochemistry
PubMed ID8241124
'The Bacillus thuringiensis var. israelensis (Bti) cytolytic toxin is hypothesized to exert its toxic activity via pore formation in the cell membrane as a result of the aggregation of several monomers. To gain insight into the toxin''s mode of action, 2 putative hydrophobic 22 amino acid peptides were synthesized and ... More
A leucine zipper-like sequence from the cytoplasmic tail of the HIV-1 envelope glycoprotein binds and perturbs lipid bilayers.
AuthorsKliger Y, Shai Y
JournalBiochemistry
PubMed ID9136877
'HIV-1 transmembrane envelope glycoprotein (gp41) has an unusually long cytoplasmic domain that has secondary associations with the inner leaflet of the membrane. Two highly amphiphatic alpha-helices in the cytoplasmic domain of gp41 have previously been shown to interact with lipid bilayers. We have detected a highly conserved leucine zipper-like sequence ... More
Mode of action of the antibacterial cecropin B2: a spectrofluorometric study.
AuthorsGazit E, Lee WJ, Brey PT, Shai Y
JournalBiochemistry
PubMed ID8075068
'Cecropin B2 (CecB) is a 35 amino acid residue, antibacterial peptide that was isolated from the hemolymph and cuticular matrix of the silkworm, Bombyx mori. Synthetic peptides with sequences corresponding to CecB and its truncated analogue, [3-->35]CecB, were synthesized and selectively labeled at their N-terminal amino acids with either 7-nitrobenz-2-oxa-1,3-diazol-4-yl ... More
Apolipoprotein C-II39-62 activates lipoprotein lipase by direct lipid-independent binding.
'Apolipoprotein C-II (apoC-II) is an exchangeable plasma apolipoprotein and an endogenous activator of lipoprotein lipase (LpL). Genetic deficiencies of apoC-II and overexpression of apoC-II in transgenic mice are both associated with severe hyperlipidemia, indicating a complex role for apoC-II in the regulation of blood lipid levels. ApoC-II exerts no effect ... More
Effect of nonpolar substitutions of the conserved Phe11 in the fusion peptide of HIV-1 gp41 on its function, structure, and organization in membranes.
AuthorsPritsker M, Rucker J, Hoffman TL, Doms RW, Shai Y
JournalBiochemistry
PubMed ID10471286
'The fusion domain of the HIV-1 envelope glycoprotein (gp120-gp41) is a conserved hydrophobic region located at the N-terminus of the transmembrane subunit (gp41). A prominent feature of this domain is a conserved five-residue "FLGFL" sequence at positions 8-12. Mutation of the highly conserved Phe(11) to Val (F11V), presumed not to ... More
Synthetic S-2 and H-5 segments of the Shaker K+ channel: secondary structure, membrane interaction, and assembly within phospholipid membranes.
AuthorsPeled H, Shai Y
JournalBiochemistry
PubMed ID8003486
'Current models of voltage-activated K+ channels predict that the channels are formed by the coassembly of four polypeptide monomers, each of which consists of six transmembrane segments (S1-S6) and long terminal domains. The aqueous pores are thought to be composed of the conserved H-5 regions contributed by four monomers. In ... 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
Selective cytotoxicity of dermaseptin S3 toward intraerythrocytic Plasmodium falciparum and the underlying molecular basis.
AuthorsGhosh JK, Shaool D, Guillaud P, Cicéron L, Mazier D, Kustanovich I, Shai Y, Mor A
JournalJ Biol Chem
PubMed ID9395500
'The antimicrobial activity of various naturally occurring microbicidal peptides was reported to result from their interaction with microbial membrane. In this study, we investigated the cytotoxicity of the hemolytic peptide dermaseptin S4 (DS4) and the nonhemolytic peptide dermaseptin S3 (DS3) toward human erythrocytes infected by the malaria parasite Plasmodium falciparum. ... 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
Membrane interaction and self-assembly within phospholipid membranes of synthetic segments corresponding to the H-5 region of the shaker K+ channel.
AuthorsPeled H, Shai Y
JournalBiochemistry
PubMed ID8347593
'The voltage-activated K+ channels are assumed to be formed by the coassembly of four polypeptide monomers. Each of these monomers is postulated to consist of six transmembrane segments (S1 to S6), and long N- and C-terminal domains. The highly conserved linker, H-5, between the fifth and the sixth transmembrane segments, ... More
Distribution and lateral mobility of GABA/benzodiazepine receptors on nerve cells.
'The distribution and mobility of GABA/benzodiazepine receptors has been examined on living nerve cells by fluorescence digital imaging and fluorescence photobleach recovery with 2 novel fluorescent derivatives of the benzodiazepines Ro7-1986 and 1012S. These fluorescent derivatives retain their high affinity for the GABA/benzodiazepine receptor complex with Ks of 79 and ... More
Influences of metal ions on the reaction of amino and imino acids with fluorogenic reagents.
AuthorsMiyano H, Toyo'oka T, Imai K, Nakajima T
JournalAnal Biochem
PubMed ID3936376
'When a twofold excess of metal ions (Cu2+, Ni2+, Zn2+, Mg2+, Ca2+, Fe3+, and Al3+) was added to a reaction medium of amino acids (1-50 microM each) with the fluorogenic reagents NBD-F (4-fluoro-7-nitrobenzo-2-oxa-1,3-diazole), DNS-Cl (5-N,N-dimethylaminonaphthalenesulfonyl chloride), OPA (o-phthalaldehyde), and fluorescamine (4-phenylspiro[furan-2(3H),1''-phthalan]-3,3''-dione), a reduction of derivatization was observed. The effect was ... More
Ultramicroanalysis of reducing carbohydrates by capillary electrophoresis with laser-induced fluorescence detection as 7-nitro-2,1,3-benzoxadiazole-tagged N-methylglycamine derivatives.
AuthorsHonda S, Okeda J, Iwanaga H, Kawakami S, Taga A, Suzuki S, Imai K
JournalAnal Biochem
PubMed ID11038280
'A method for ultramicroanalysis of carbohydrates using capillary electrophoresis with laser-induced fluorescence detection was developed, based on precapillary conversion to 7-nitro-2,1, 3-benzoxadiazole (NBD)-tagged N-methylglycamines. Although the derivatization involves two-step reactions, i.e., reductive N-methylamination followed by condensation with NBD-F, they can be carried out in a one-pot fashion and proceed quantitatively ... More
Determination of free D-proline and D-leucine in the brains of mutant mice lacking D-amino acid oxidase activity.
AuthorsHamase K, Inoue T, Morikawa A, Konno R, Zaitsu K
JournalAnal Biochem
PubMed ID11700980
'A new procedure to accurately measure a trace amount of d-proline in biological samples has been developed. This D-amino acid was derivatized with 4-fluoro-7-nitro-2,1,3-benzoxadiazole and was determined by a column-switching HPLC system, a combination of a micro-ODS column and a chiral column. The detection limit for D-proline spiked in a ... More
Sensitive determination of nitrotyrosine in human plasma by isocratic high-performance liquid chromatography.
AuthorsKamisaki Y, Wada K, Nakamoto K, Kishimoto Y, Kitano M, Itoh T
JournalJ Chromatogr B Biomed Appl
PubMed ID8953177
'A highly sensitive and simple isocratic high-performance liquid chromatographic method was developed for determination of 3-nitrotyrosine in human plasma with precolumn derivatization with 4-fluoro-7-nitrobenzo-2-oxa-1,3-diazole. The precision of the method was satisfactory (coefficient of variation 4.8%), and the detection limit was established at 0.1 pmol of 3-nitrotyrosine allowing the determination at ... More
Recent advances in methods for the analysis of catecholamines and their metabolites.
AuthorsTsunoda M
JournalAnal Bioanal Chem
PubMed ID16924378
'Catecholamines, for example epinephrine, norepinephrine, and dopamine, are widely distributed and are important neurotransmitters and hormones in mammalian species. Several methods have been developed for analysis of catecholamines and related compounds. Determination of catecholamines in biological fluids has enabled us to clarify the physiological role played by these amines. Catecholamine ... More
Derivatization with fluorogenic benzofurazan reagents of amino acid enantiomers and their separation on a Pirkle type column.
AuthorsImai K, Fukushima T
JournalBiomed Chromatogr
PubMed ID8305859
'L- and D-Amino acids (Leu or Phe) were derivatized with fluorogenic reagents, 4-fluoro-7-nitro-2,1,3-benzoxadiazole (NBD-F), 4-(N,N-dimethylaminosulfonyl)-7-fluoro-2,1,3-benzoxadiazole (DBD-F), 4-aminosulfonyl-7-fluoro-2,1,3-benzoxadiazole (ABD-F) and 5-(N,N-dimethylamino)naphthalene-1-sulfonylchloride (DNS-CI), and separated on a Pirkle type column, Sumichiral OA 2500 (S) ((S)-1-naphthylglycyl-3,5-dinitrophenylamide silica gel) with a mobile phase of 20 mM ammonium acetate in methanol. The fluorometric detection of ... More
Amino acid composition analysis of minute amounts of cysteine-containing proteins using 4-(aminosulfonyl)-7-fluoro-2,1,3-benzoxadiazole and 4-fluoro-7-nitro-2,1,3-benzoxadiazole in combination with HPLC.
AuthorsToyo'oka T, Miyano H, Imai K
JournalBiomed Chromatogr
PubMed ID3506813
'The simultaneous determination of amino acid composition including cysteine of egg albumin, a model protein containing a/s cysteine residue, is reported. All the thiol groups of the cysteine residue(s) of egg albumin were labelled with 4-(aminosulfonyl)-7-fluoro-2,1,3-benzoxadiazole, a fluorogenic reagent for thiol groups. The labeled egg albumin was hydrolyzed in 6N ... More
A peptide derived from a conserved domain of Sendai virus fusion protein inhibits virus-cell fusion. A plausible mode of action.
AuthorsGhosh JK, Shai Y
JournalJ Biol Chem
PubMed ID9516418
'SV-201, a peptide derived from a conserved and potentially amphipathic region (amino acids 201-229) in the Sendai virus ectodomain, specifically inhibited virus-mediated hemolysis only when added to virions prior to their attachment to red blood cells. Sendai virus-mediated hemagglutinin assay in the presence of SV-201 demonstrated that the peptide does ... More
The preparation and application of functionalised synthetic oligonucleotides: III. Use of H-phosphonate derivatives of protected amino-hexanol and mercapto-propanol or -hexanol.
AuthorsSinha ND, Cook RM
JournalNucleic Acids Res
PubMed ID3362678
'Syntheses of H-phosphonate salts (4a-e) of N/S-protected alcohols such as 6-aminohexan-1-ol, 3-mercaptopropan-1-ol and 6-mercaptohexan-1-ol are described using 2-chloro-5,6-benzo-1,3,2-phosphorin-4-one (2) as the phosphonylating agent. The H-phosphonate salts (4a-e), in the presence of pivaloyl chloride or adamantoyl chloride as an activator, were coupled to the 5''-end of synthetic oligonucleotides on solid supports ... More
Gelsolin binds to polymeric actin at a low rate.
AuthorsSchoepper B, Wegner A
JournalJ Biol Chem
PubMed ID1321131
'Association of gelsolin with actin filament subunits was investigated by the decrease of the fluorescence intensity of a 7-nitro-2-oxa-1,3-diazole (NBD) label covalently linked to gelsolin. The rate constant of this reaction was found to be 4 x 10(3) M-1 s-1. Binding of NBD-labeled gelsolin to monomeric actin proceeds at a ... More
Interaction of the mammalian antibacterial peptide cecropin P1 with phospholipid vesicles.
AuthorsGazit E, Boman A, Boman HG, Shai Y
JournalBiochemistry
PubMed ID7547876
'Cecropins are positively charged antibacterial polypeptides that were originally isolated from insects. Later on a mammalian homologue, cecropin P1 (CecP), was isolated from pig intestines. While insect cecropins are highly potent against both Gram-negative and Gram-positive bacteria, CecP is as active as insect cecropins against Gram-negative but has reduced activity ... More
Preparation of fluorescence-labeled GM1 and sphingomyelin by the reverse hydrolysis reaction of sphingolipid ceramide N-deacylase as substrates for assay of sphingolipid-degrading enzymes and for detection of sphingolipid-binding proteins.
AuthorsNakagawa T, Tani M, Kita K, Ito M
JournalJ Biochem (Tokyo)
PubMed ID10467178
'Sphingolipid ceramide N-deacylase is an enzyme capable of hydrolyzing the N-acyl linkages of ceramides of various sphingolipids. Recently, it was found that the enzyme catalyzes the reverse hydrolysis reaction in which free fatty acids are condensed to lyso-sphingolipids to produce sphingolipids. This paper describes a simple method for the synthesis ... More
Effect of cholesterol and charge on pore formation in bilayer vesicles by a pH-sensitive peptide.
AuthorsNicol F, Nir S, Szoka FC
JournalBiophys J
PubMed ID8968598
'The effect of cholesterol on the bilayer partitioning of the peptide GALA (WEAALAEALAEALAEHLAEALAEALEALAA) and its assembly into a pore in large unilamellar vesicles composed of neutral and negatively charged phospholipids has been determined. GALA undergoes a conformational change from a random coil to an amphipathic alpha-helix when the pH is ... More
Structure-function study of a heptad repeat positioned near the transmembrane domain of Sendai virus fusion protein which blocks virus-cell fusion.
AuthorsGhosh JK, Peisajovich SG, Ovadia M, Shai Y
JournalJ Biol Chem
PubMed ID9765238
'A synthetic heptad repeat, SV-473, derived from Sendai virus fusion protein is a potent inhibitor of virus-cell fusion. In order to understand the mechanism of the inhibitory effect, we synthesized and fluorescently labeled SV-465, an extended version of SV-473 by one more heptad, its mutant peptide A17,24-SV-465, in which two ... More
Liquid chromatographic determination of amino and imino acids and thiols by postcolumn derivatization with 4-fluoro-7-nitrobenzo-2,1,3-oxadiazole.
AuthorsWatanabe Y, Imai K
JournalAnal Chem
PubMed ID6638514
Determination of serum sulphonylureas by high-performance liquid chromatography with fluorimetric detection.
AuthorsIgaki A, Kobayashi K, Kimura M, Sakoguchi T, Matsuoka A
JournalJ Chromatogr
PubMed ID2778016
High-performance liquid chromatography and sensitive detection of amino acids derivatized with 7-fluoro-4-nitrobenzo-2-oxa-1,3-diazole.
AuthorsWatanabe Y, Imai K
JournalAnal Biochem
PubMed ID7316179
Derivatization of posttranslationally modified amino acids.
AuthorsTeerlink T
JournalJ Chromatogr B Biomed Appl
PubMed ID7820276
After a brief overview of posttranslational modifications of protein amino acids, the use of various derivatizing reagents for amino acid analysis is discussed. Derivatization and chromatographic separation of hydroxyproline, methylhistidine, and phosphorylated amino acids are discussed in detail to illustrate some of the strategies that can be applied to the ... More
Choice of different dyes to label tyrosine and nitrotyrosine.
AuthorsMassip C, Riollet P, Quemener E, Bayle C, Salvayre R, Couderc F, Caussé E
JournalJ Chromatogr A
PubMed ID12498250
In this work, we will present some attempts to analyze tyrosine and nitrotyrosine using capillary electrophoresis and either UV-Visible detection or laser-induced fluorescence (LIF) detection. An argon ion (488 nm) laser is used for fluorescein isothiocyanate (FITC) and 7-fluoro-4-nitro-2,1,3-benzoxadiazole (NBD-F). A near infrared (780 nm) laser is used for NIR ... More
Efficient methods for attaching non-radioactive labels to the 5' ends of synthetic oligodeoxyribonucleotides.
AuthorsAgrawal S, Christodoulou C, Gait MJ
JournalNucleic Acids Res
PubMed ID3748808
The syntheses are described of two types of linker molecule useful for the specific attachment of non-radioactive labels such as biotin and fluorophores to the 5' terminus of synthetic oligodeoxyribonucleotides. The linkers are designed such that they can be coupled to the oligonucleotide as a final step in solid-phase synthesis ... More
Determination of tris(hydroxymethyl)aminomethane (tromethamine) in human plasma and urine by high-performance liquid chromatography with fluorescence detection.
AuthorsMorris MJ, Hsieh JY
JournalJ Chromatogr
PubMed ID8120117
Determination of tromethamine (2-amino-2-hydroxymethyl-1,3-propanediol) in human plasma and urine has been developed and validated. The method utilizes reversed-phase high-performance liquid chromatographic separation and fluorescence detection of a pre-column derivative. The assay was linear in the ranges of 1-200 micrograms/ml plasma and 5-500 micrograms/ml urine with accuracies (mean percent recovery) all ... More
Fluorimetric assay of phospholipase A acting on biomembrane phospholipids.
AuthorsSaris NE, Somerharju P
JournalActa Chem Scand
PubMed ID2487787
A sensitive phospholipase A assay suitable for organelle activities is described. Activation of the enzyme produces an increase in membrane lysophospholipids. The amino groups of extracted lipids were derivatized with 4-fluoro-7-nitrobenzo-2-oxa-1,3-diazole and the amounts of phosphatidylethanolamine and its lysoform were quantitated using HPLC equipped with a SiO2 column and a ... More
Sensitive determination of enantiomers of amino acids derivatized with the fluorogenic reagent, 4-fluoro-7-nitro-2,1,3-benzoxadiazole, separated on a Pirkle-type column, Sumichiral OA 2500(S).
AuthorsImai K, Fukushima T, Uzu S
JournalBiomed Chromatogr
PubMed ID8318837
Some L- and D-amino acids (Phe or Leu) were derivatized with a fluorogenic reagent, 4-fluoro-7-nitro-2,1,3-benzoxadiazole (NBD-F) and separated on a Pirkle-type column, Sumichiral OA 2500(S) [(S)-1-naphthylglycyl-3,5-dinitrophenylamide silica gel] with a mobile phase of 20 mM ammonium acetate in methanol. The fluorometric detection was made at 530 nm with excitation at ... More
The synthesis of oligonucleotides containing an aliphatic amino group at the 5' terminus: synthesis of fluorescent DNA primers for use in DNA sequence analysis.
AuthorsSmith LM, Fung S, Hunkapiller MW, Hunkapiller TJ, Hood LE
JournalNucleic Acids Res
PubMed ID4000959
A rapid and versatile method has been developed for the synthesis of oligonucleotides which contain an aliphatic amino group at their 5' terminus. This amino group reacts specifically with a variety of electrophiles, thereby allowing other chemical species to be attached to the oligonucleotide. This chemistry has been utilized to ... More
Sensitive detection of selected cholinergic channel activators derivatized with 7-fluoro-4-nitrobenzo-2-oxa-1,3-diazole.
AuthorsHui Y, Marsh KC
JournalJ Pharm Biomed Anal
PubMed ID8833975
A high-performance liquid chromatographic method with fluorescence detection was developed for a series of cholinergic channel activators using 7-fluoro-4-nitrobenzo-2-oxa-1,3-diazole (NBD-F) as a fluorescent labeling reagent. This method includes three separate steps: extraction of parent compound and internal standard with organic solvent from plasma, reaction of parent and internal standard in ... More
A novel peptide inhibitor of the myosin ATPase from an Okinawan marine sponge.
AuthorsHiratsuka T
JournalJ Biol Chem
PubMed ID2530220
A substance which inhibits the myosin ATPase has been detected from an Okinawan marine sponge. The inhibitor has been isolated from the methanol-soluble extract of the sponge by gel filtration and hydrophobic chromatography. The isolated inhibitor is an amphipathic peptide, which is rich in Asp, Glu, Ser, and Gly, and ... More
Selective fluorescent labeling of the 50-, 26-, and 20-kilodalton heavy chain segments of myosin ATPase.
AuthorsHiratsuka T
JournalJ Biochem (Tokyo)
PubMed ID2959655
7-Diethylamino-3-(4'-isothiocyanatophenyl)-4-methylcoumarin (CPI), rhodamine B isothiocyanate (RITC), and 4-bromomethyl-6,7-dimethoxycoumarin (BDMC), fluorescent reagents that can react covalently with amino or sulfhydryl groups, have been used to label myosin subfragment-1 (S-1) ATPase. The conditions under which CPI, RITC, and BDMC selectively label the 50-, 26-, and 20-kDa segments of the S-1 heavy chain, ... More
Determination of plasma free 3-nitrotyrosine and tyrosine by reversed-phase liquid chromatography with 4-fluoro-7-nitrobenzofurazan derivatization.
AuthorsZhang WZ, Lang C, Kaye DM,
JournalBiomed Chromatogr
PubMed ID17236239
Oxidative stress plays an important role in pathogenesis of many diseases. Measurement of 3-nitrotyrosine (NO(2)Tyr), as a potential biomarker for nitric oxide-mediated damage, has recently been the focus of particular attention. We have developed an HPLC method with NBD-F pre-column derivatization followed by C(18) cartridge cleaning. Using this method we ... More
A fully automated amino acid analyzer using NBD-F as a fluorescent derivatization reagent.
AuthorsAoyama C, Santa T, Tsunoda M, Fukushima T, Kitada C, Imai K
JournalBiomed Chromatogr
PubMed ID15386506
A fully automated amino acid analyzer using NBD-F (4- fluoro-7-nitro-2,1,3-benzoxadiazole) as a fluorescent derivatization reagent was developed. The whole analytical process was fully automated from derivatization, injection to HPLC separation and quantitation. The derivatization reaction conditions were re-evaluated and optimized. Amino acids were derivatized by NBD-F for 40 min at ... More
Inhibition of monoamine oxidase by 7-chloro-4-nitrobenzofurazan.
AuthorsFu RC, Liu XF, Chen SU
JournalJ Neurochem
PubMed ID2384754
7-Chloro-4-nitrobenzofurazan (NBD-Cl) is a potent inhibitor of both types of monoamine oxidase (MAO). NBD-Cl competitively inhibited the oxidative deamination of kynuramine catalyzed by human placenta MAO-A, the oxidative deamination of benzylamine catalyzed by bovine liver MAO-B, the oxidative deamination of serotonin catalyzed by rat brain MAO-A, and the oxidative deamination ... More
Fluorogenic reactions for biomedical chromatography.
AuthorsOhkura Y, Kai M, Nohta H
JournalJ Chromatogr B Biomed Appl
PubMed ID7820282
A number of fluorogenic reactions, which have been used for HPLC detection systems by means of pre- and/or postcolumn derivatization, are surveyed with respect to both sensitivity and selectivity for the determination of biomedically important substances. For the derivatization of the substances, two types of fluorogenic reactions, fluorescence-generating and fluorescence-tagging, ... More
Creation of an on-chip enzyme reactor by encapsulating trypsin in sol-gel on a plastic microchip.
AuthorsSakai-Kato K, Kato M, Toyo'oka T
JournalAnal Chem
PubMed ID12585462
Trypsin-encapsulated sol-gel was fabricated in situ onto a plastic microchip to form an on-chip bioreactor that integrates tryptic digestion, separation, and detection. Trypsin-encapsulated sol-gel, which is derived from alkoxysilane, was fabricated within a sample reservoir (SR) of the chip. Fluorescently labeled ArgOEt and bradykinin were digested within the SR followed ... More
Probing the binding domain of the Saccharomyces cerevisiae alpha-mating factor receptor with rluorescent ligands.
AuthorsDing FX, Lee BK, Hauser M, Davenport L, Becker JM, Naider F
JournalBiochemistry
PubMed ID11170434
Three analogues of the alpha-mating factor pheromone of Saccharomyces cerevisiae containing the 7-nitrobenz-2-oxa-1,3-diazol-4-yl (NBD) group were synthesized that had high binding affinity to the receptor and retained biological activity. The fluorescence emission maximum of the NBD group in [K7(NBD),Nle(12)]-alpha-factor was blue shifted by 35 nm compared to buffer when the ... More
Chemistry and biology of N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)-labeled lipids: fluorescent probes of biological and model membranes.
AuthorsChattopadhyay A
JournalChem Phys Lipids
PubMed ID2191793
Lipids that are covalently labeled with the 7-nitrobenz-2-oxa-1,3-diazol-4-yl (NBD) group are widely used as fluorescent analogues of native lipids in model and biological membranes to study a variety of processes. The fluorescent NBD group may be attached either to the polar or the apolar regions of a wide variety of ... More
Involvement of the 50-kDa peptide of myosin heads in the ATPase activity revealed by fluorescent modification with 4-fluoro-7-nitrobenz-2-oxa-1,3-diazole.
AuthorsHiratsuka T
JournalJ Biol Chem
PubMed ID2940240
The fluorescent reagent 4-fluoro-7-nitrobenz-2-oxa-1,3-diazole (NBD-F) reacted specifically with 1.9 lysyl residues/mol of the myosin subfragment-1 (S-1) ATPase. When 1.9 lysyl residues were modified, the K+- and Ca2+-ATPase activities were almost completely inhibited, whereas the Mg2+-ATPase activity was increased to 180% of original activity. The actin-activated Mg2+-ATPase activity was decreased to ... More
Crystal structures of murine carnitine acetyltransferase in ternary complexes with its substrates.
AuthorsHsiao YS, Jogl G, Tong L
JournalJ Biol Chem
PubMed ID16870616
Carnitine acyltransferases catalyze the reversible exchange of acyl groups between coenzyme A (CoA) and carnitine. They have important roles in many cellular processes, especially the oxidation of long-chain fatty acids in the mitochondria for energy production, and are attractive targets for drug discovery against diabetes and obesity. To help define ... More
Synchronous luminescence: a new detection technique for multiple fluorescent probes used for DNA sequencing.
AuthorsStevenson CL, Johnson RW, Vo-Dinh T
JournalBiotechniques
PubMed ID8074876
A method fo nonradioactive DNA sequencing, which has been marketed commercially, uses four different fluorescent tags to label DNA fragments and fixed-wavelength excitation/fluorescence detection of the labels. This study presents an alternative method of detection based on synchronous luminescence (SL), in which both excitation and emission wavelengths are scanned simultaneously. ... More
Methyl-beta-cyclodextrin modified micellar electrokinetic capillary chromatography with laser-induced fluorescence for separation and detection of phospholipids.
AuthorsLe Zhang Krylov SN, Hu S, Dovichi NJ
JournalJ Chromatogr A
PubMed ID11100855
Micellar electrokinetic capillary chromatography (MECC) with laser-induced fluorescence detection was applied to the separation of amino group-containing phospholipids including phosphatidylethanolamine (PE), phosphatidylserine (PS), lysophosphatidylethanolamine (LysoPE), and lysophosphatidylserine (LysoPS). A fluorogenic dye, 3-(2-furoyl)quinoline-2-carboxaldehyde (FQ), was successfully used to fluorescently label these phospholipids. 4-Fluoro-7-nitrobenzofurazan only produced fluorescent product from LysoPE and PE; ... More
Determination of rat blood S-D-lactoylglutathione by a column-switching high-performance liquid chromatography with precolumn fluorescence derivatization with 4-fluoro-7-nitro-2,1,3-benzoxadiazole.
AuthorsUchino E, Fukushima T, Tsunoda M, Santa T, Imai K
JournalAnal Biochem
PubMed ID15203323
A method for the determination of S-d-lactoylglutathione (SLG), an intermediate metabolite of the glyoxalase system, in rat blood is described. After hemolysis and deproteinization of 30 microl of rat blood, SLG in the blood was determined by a column-switching HPLC system with precolumn fluorescence derivatization with a fluorogenic reagent, 4-fluoro-7-nitro-2,1,3-benzoxadiazole ... More
A fluorescent analog of colcemid, N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)-colcemid, as a probe for the colcemid-binding sites of tubulin and microtubules.
AuthorsHiratsuka T, Kato T
JournalJ Biol Chem
PubMed ID3571259
The synthesis and biological testing of the fluorescent analog of colcemid, N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)-colcemid (NBD-colcemid), are here described. NBD-colcemid exhibited a visible absorption maximum at 465 nm and fluoresced in the range of 520-540 nm, highly in environments of low polarity, whereas only slightly in aqueous solution. The addition of NBD-colcemid to ... More
Determination of mycotoxins produced by Fusarium isolates from banana fruits by capillary gas chromatography and high-performance liquid chromatography.
AuthorsJiménez M, Mateo R
JournalJ Chromatogr A
PubMed ID9299747
A method of analysis for trichothecenes (nivalenol, deoxynivalenol, 3- and 15-acetyldeoxynivalenol, diacetoxyscirpenol, neosolaniol, T-2 tetraol, T-2 and HT-2 toxins), zearalenone and zearalenols, and another method for determination of fumonisin B1 are described and applied to cultures of Fusarium isolated from bananas. Both methods were adapted from different techniques of extraction, ... More
Automated column-switching high-performance liquid chromatography system for quantifying N-methyl-D- and -L-aspartate.
AuthorsSekine M, Fukuda H, Nimura N, Furuchi T, Homma H
JournalAnal Biochem
PubMed ID12413481
The occurrence and biological significance of the D-amino acids, N-methyl-D-aspartate (NMDA) and N-methyl-L-aspartate (NMLA), have been recently studied in a variety of living organisms. In this study, we established a highly sensitive and reliable fluorometric HPLC system for determining levels of N-methyl-aspartate (NMA). The system comprises fluorescent derivatization of NMA ... More
Enhancing capillary liquid chromatography/tandem mass spectrometry of biogenic amines by pre-column derivatization with 7-fluoro-4-nitrobenzoxadiazole.
AuthorsSong Y, Quan Z, Evans JL, Byrd EA, Liu YM
JournalRapid Commun Mass Spectrom
PubMed ID15116426
This paper describes a capillary liquid chromatography/tandem mass spectrometry (LC/MS/MS) determination of biogenic amines enhanced by pre-column derivatization with 7-fluoro-4-nitrobenzoxadiazole (NBD-F). Biogenic amines including tryptamine, N-methylsalsolinol, histamine, and agmatine were studied. The biogenic NBD-amine derivatives could be quantitatively enriched in-line on 20 x 0.25 mm capillary columns packed in-house with ... More
Modification of gelsolin with 4-fluoro-7-nitrobenz-2-oxa-1,3-diazole.
AuthorsDoi Y, Hashimoto T, Yamaguchi H, Vertut-Doï A
JournalEur J Biochem
PubMed ID1649046
Pig plasma gelsolin was modified with the fluorescent reagent 4-fluoro-7-nitrobenz-2-oxa-1,3-diazole (NBD-F) for lysyl residues. The relationship between the gelsolin activity and the degree of NBD labeling suggested that a single lysyl residue, which reacted five times slower than the other reactive lysyl residues, was essential for the activity. Taking advantage ... More
Determination of amphetamine-related compounds by high-performance liquid chromatography with chemiluminescence and fluorescence detections.
AuthorsHayakawa K, Hasegawa K, Imaizumi N, Wong OS, Miyazaki M
JournalJ Chromatogr
PubMed ID2722984
High-performance liquid chromatography with chemiluminescence detection has been established for the determination of trace levels of amphetamine-related compounds (APs) after fluorigenic derivatization. Bis(2,4,6-trichlorophenyl) oxalate and hydrogen peroxide in acetonitrile was used as a post-column chemilumigenic reagent. As derivatization reagents, dansyl chloride (Dns-Cl), 4-fluoro-7-nitrobenzoxadiazole (NBD-F) and naphtalene-2,3-dicarbaldehyde (NDA) were compared. Dns-Cl ... More
Characterization of visible dyes for four-decay fluorescence detection in DNA sequencing.
AuthorsNunnally BK, He H, Li LC, Tucker SA, McGown LB
JournalAnal Chem
PubMed ID9212706
Dyes of several classes were investigated as candidates for use in a multiplex, four-decay fluorescence detection scheme for DNA sequencing. The dyes include nitrobenzofuran dyes, rhodamine dyes, fluorescein dyes, cyanine dyes, Nile Red, and BODIPY dyes. Based on the results of fluorescence spectral and lifetime studies, an initial set of ... More
Capillary electrophoretic and micellar electrokinetic separations of asymmetric dimethyl-L-arginine and structurally related amino acids: quantitation in human plasma.
We report the development of efficient electrophoretic methods for the separation and quantification of L-arginine and six naturally occurring derivatives that are structurally and functionally related. Capillary electrophoresis (CE) employing a concentrated borate buffer at pH 9.4 achieves the separation of mixtures containing dimethyl-L-arginine, NG-monomethyl-L-arginine, L-arginine, L-homoarginine, L-ornithine, and L-citrulline ... More
Helix-helix association of a lipid-bound amphipathic alpha-helix derived from apolipoprotein C-II.
The interaction of a peptide derived from the sequence of apolipoprotein C-II (apoC-II) with a model lipid surface has been investigated by fluorescence spectroscopy. ApoC-II19-39, labeled at the N-terminus with 7-nitrobenz-2-oxa-1,3-diazole (NBD), bound to small unilamellar vesicles of phosphatidylcholine with a dissociation constant of 6 microM. The lipid-bound NBD-labeled peptide ... More
Study of ligand-receptor interactions by fluorescence correlation spectroscopy with different fluorophores: evidence that the homopentameric 5-hydroxytryptamine type 3As receptor binds only one ligand.
AuthorsWohland T, Friedrich K, Hovius R, Vogel H
JournalBiochemistry
PubMed ID10393542
The 5-hydroxytryptamine receptor of type 3 was investigated by fluorescence correlation spectroscopy (FCS). Binding constants of fluorescently labeled ligands, the stoichiometry, and the mass of the receptor are readily accessible by this technique, while the duration of measurement is on the order of seconds to minutes. The receptor antagonist 1,2,3, ... More
Interaction of fluorescently labeled pardaxin and its analogues with lipid bilayers.
AuthorsRapaport D, Shai Y
JournalJ Biol Chem
PubMed ID1748653
Fluorescence measurements were used to monitor the interaction of the neurotoxin pardaxin and its analogues with membranes. Eight peptides were selectively labeled with the fluorophore 7-nitrobenz-2-oxa-1,3-diazole-4-yl, either at their N-terminal or at their C-terminal. No detectable changes in membrane permeability or hemolytic activity were observed upon modification. Upon the titration ... More
Highly sensitive determination of lanthanides by capillary electrophoresis with direct visible detection after precapillary complexation with aromatic polyaminocarboxylate and additionally applying dynamic ternary complexation with nitrilotriacetic acid.
AuthorsSaito S, Danzaka N, Hoshi S
JournalElectrophoresis
PubMed ID16800028
A newly synthesized aromatic polyaminocarboxylate (NBD-ABEDTA, H(4)L) was applied to precapillary derivatizing capillary electrophoresis as a chelating reagent for lanthanide ions (Ln(3+)). The Ln-L complexes provide both kinetic stability on dissociation due to their methyl-EDTA coordinating structure, and high light absorptivity (epsilon(max) = 2.4 x 10(4) cm(-1) mol(-1) dm(3)) in ... More
Stabilization of calmodulin-dependent protein kinase II through the autoinhibitory domain.
AuthorsIshida A, Fujisawa H
JournalJ Biol Chem
PubMed ID7836445
The active 30-kDa chymotryptic fragment of calmodulin-dependent protein kinase II (CaM kinase II), devoid of the autoinhibitory domain, and the enzyme, autothiophosphorylated at Thr286/Thr287, were much more labile than was the original native enzyme. They were markedly stabilized by synthetic peptides, designed after the sequence around the autophosphorylation site in ... More
Transmission of ADP.vanadate-induced conformational changes to three peptide segments of myosin subfragment-1.
AuthorsHiratsuka T
JournalJ Biol Chem
PubMed ID2229042
In order to study the conformational changes associated with formation of the stable ternary complex of myosin subfragment-1 (S-1) with ADP and orthovanadate (Vi), S-1 was fluorescently labeled with 9-anthroylnitrile, 4-fluoro-7-nitrobenz-2-oxa-1,3-diazole, and 5-(iodoacetamido) fluorescein at the 23-, 50-, and 20-kDa peptide segments of S-1, respectively (Hiratsuka, T. (1989) J. Biol. ... More
Synthetic peptides corresponding to the calmodulin-binding domains of skeletal muscle myosin light chain kinase and human erythrocyte Ca2+ pump interact with and permeabilize liposomes and cell membranes.
AuthorsEshel Y, Shai Y, Vorherr T, Carafoli E, Salomon Y
JournalBiochemistry
PubMed ID8392369
Synthetic calmodulin-binding (CaM-binding) peptides (CBPs) representing CaM-binding domains of Ca2+/CaM-dependent enzymes have been reported to interfere with the activity of the melanocyte-stimulating hormone (MSH) receptor function in melanoma cells [Gerst, J. E., & Salomon, Y. (1988) J. Biol. Chem. 263, 7073-7078]. We postulated that membrane lipids may play an important ... More
Secondary structure and membrane localization of synthetic segments and a truncated form of the IsK (minK) protein.
AuthorsBen-Efraim I, Strahilevitz J, Bach D, Shai Y
JournalBiochemistry
PubMed ID8204631
IsK, also referred to as minK, is a membrane protein consisting of 130 amino acids and localized mainly in epithelial cells but also in human T lymphocytes. Depending on the cRNA concentration that was injected into Xenopus oocytes, IsK and its truncated forms can induce either a K+ current alone ... More
Structural and functional characterization of the alpha 5 segment of Bacillus thuringiensis delta-endotoxin.
AuthorsGazit E, Shai Y
JournalBiochemistry
PubMed ID8384882
One of the most conserved sequences in various delta-endotoxins is the 30 amino acid long block I. Block I of cryIIIA delta-endotoxin contains a 23 amino acid amphiphilic alpha-helix termed alpha 5. The potential involvement of this alpha 5 helix in the toxic mechanism of delta-endotoxin was examined. For this ... More
Participation of two fusion peptides in measles virus-induced membrane fusion: emerging similarity with other paramyxoviruses.
AuthorsSamuel O, Shai Y
JournalBiochemistry
PubMed ID11170461
Paramyxoviruses penetrate into their host cells by fusing their membranes with the plasma membrane. The hydrophobic N terminus of their F1 protein, termed the 'fusion peptide', is thought to be responsible for this process. Recently, an additional internal fusion peptide, homologous in sequence to the N-terminal fusion peptide of HIV-1, ... More
Determination of hydrolysed fumonisin B1 in alkali-processed corn foods.
AuthorsScott PM, Lawrence GA
JournalFood Addit Contam
PubMed ID8885322
Treatment of fumonisin B1 (FB1)-contaminated corn with calcium hydroxide solution is known to cause large losses of FB1 and formation of the aminopentol AP1 by hydrolysis. Methodology was developed for determination of AP1 in foods manufactured from calcium hydroxide-processed corn. The ground food (tortilla chips, nacho chips, taco shells, or ... More
Reversible surface aggregation in pore formation by pardaxin.
AuthorsRapaport D, Peled R, Nir S, Shai Y
JournalBiophys J
PubMed ID8744290
The mechanism of leakage induced by surface active peptides is not yet fully understood. To gain insight into the molecular events underlying this process, the leakage induced by the peptide pardaxin from phosphatidylcholine/ phosphatidylserine/cholesterol large unilamellar vesicles was studied by monitoring the rate and extent of dye release and by ... More
Interaction of D-amino acid incorporated analogues of pardaxin with membranes.
AuthorsPouny Y, Shai Y
JournalBiochemistry
PubMed ID1390731
The influence of specific L- to D-amino acid substitutions on the interaction of pardaxin, a shark repellent neurotoxin polypeptide, with phospholipid vesicles and human erythrocytes is described. Twelve modified, truncated, or fluorescently labeled [with the fluorophore 7-nitrobenz-2-oxa-1,3-diazole-4-yl (NBD) at their N-terminal amino acid] analogues of pardaxin were synthesized by a ... More
Determination of ABT-089 in human plasma by high performance liquid chromatography using in situ precolumn derivatization with 7-fluoro-4-nitrobenzo-2-oxa-1,3-diazole.
AuthorsBryan PD, Emry ML, El-Shourbagy TA
JournalJ Pharm Biomed Anal
PubMed ID10704009
ABT-089 is a potent, selective neuronal cholinergic channel modulator with cognition enhancing activity in several animal paradigms. A simple and sensitive chromatographic method for the specific determination of ABT-089 in human plasma has been developed and validated. The method utilizes in situ precolumn fluorescence derivatization of the sample with 7-fluoro-4-nitrobenzo-2-oxa-1,3-diazole ... More
Enantiomeric separation and sensitive determination of D,L-amino acids derivatized with fluorogenic benzofurazan reagents on Pirkle type stationary phases.
AuthorsFukushima T, Kato M, Santa T, Imai K
JournalBiomed Chromatogr
PubMed ID7734928
The enantiomeric separations of D,L-amino acids derivatized with fluorogenic reagents, 4-fluoro-7-nitro-2,1,3-benzoxadiazole (NBD-F), 4-(N,N-dimethylaminosulphonyl)-7-fluoro-2,1,3-benzoxadiazole (DBD-F) and 4-aminosulphonyl-7-fluoro-2,1,3-benzoxadiazole (ABD-F) by high-performance liquid chromatography (HPLC) on various Pirkle type chiral stationary phases (CSPs, Sumichiral OA series) with citric acid in methanol as a mobile phase were studied. Since the least retention and no ... More
The assembly and organization of the alpha 5 and alpha 7 helices from the pore-forming domain of Bacillus thuringiensis delta-endotoxin. Relevance to a functional model.
AuthorsGazit E, Shai Y
JournalJ Biol Chem
PubMed ID7852320
The pore-forming domain of Bacillus thuringiensis insecticidal CryIIIA delta-endotoxin contains two helices, alpha 5 and alpha 7, that are highly conserved within all different Cry delta-endotoxins. To gain information on the mode of action of delta-endotoxins, we have used a spectrofluorimetric approach and characterized the structure, the organization state, and ... More
Synthetic peptides corresponding to the four P regions of Electrophorus electricus Na+ channel: interaction with and organization in model phospholipid membranes.
AuthorsPouny Y, Shai Y
JournalBiochemistry
PubMed ID7779818
The hydropathy plot of the alpha subunit of the voltage-gated Na+ channel reveals four homologous repeats, each of which is homologous to Shaker type K+ channel monomer and contains six putative transmembrane segments and a hydrophobic segment within the loop connecting transmembrane segments S5 and S6. Current models predict that ... More
Coassembly of synthetic segments of shaker K+ channel within phospholipid membranes.
AuthorsPeled-Zehavi H, Arkin IT, Engelman DM, Shai Y
JournalBiochemistry
PubMed ID8639634
Increasing evidence suggests that membrane-embedded hydrophobic segments can interact within the phospholipid milieu of the membrane with varying degrees of specificity and thus contribute to the folding and oligomerization of proteins. We have used synthetic peptides corresponding to segments from the hydrophobic core of the Shaker potassium channel as a ... More
A modular strategy for tailoring fluorescent biosensors from ribonucleopeptide complexes.
AuthorsHagihara M, Fukuda M, Hasegawa T, Morii T
JournalJ Am Chem Soc
PubMed ID17002390
Fluorescent biosensors that facilitate reagentless sensitive detection of small molecules are crucial tools in the areas of therapeutics and diagnostics. However, construction of fluorescent biosensors with desired characteristics, that is, detection wavelengths and concentration ranges for ligand detection, from macromolecular receptors is not a straightforward task. An ATP-binding ribonucleopeptide (RNP) ... More
Lipopolysaccharide is transferred from high-density to low-density lipoproteins by lipopolysaccharide-binding protein and phospholipid transfer protein.
AuthorsLevels JH, Marquart JA, Abraham PR, van den Ende AE, Molhuizen HO, van Deventer SJ, Meijers JC
JournalInfect Immun
PubMed ID15784577
Lipopolysaccharide (LPS), the major outer membrane component of gram-negative bacteria, is a potent endotoxin that triggers cytokine-mediated systemic inflammatory responses in the host. Plasma lipoproteins are capable of LPS sequestration, thereby attenuating the host response to infection, but ensuing dyslipidemia severely compromises this host defense mechanism. We have recently reported ... More
The effect of cyclization of magainin 2 and melittin analogues on structure, function, and model membrane interactions: implication to their mode of action.
AuthorsUnger T, Oren Z, Shai Y
JournalBiochemistry
PubMed ID11371201
The amphipathic alpha-helical structure is a common motif found in membrane binding polypeptides including cell lytic peptides, antimicrobial peptides, hormones, and signal sequences. Numerous studies have been undertaken to understand the driving forces for partitioning of amphipathic alpha-helical peptides into membranes, many of them based on the antimicrobial peptide magainin ... More
Calcium-dependent and -independent interfacial binding and catalysis of cytosolic group IV phospholipase A2.
AuthorsHixon MS, Ball A, Gelb MH
JournalBiochemistry
PubMed ID9622504
Cytosolic group IV phospholipase A2 (cPLA2) plays a role in liberating arachidonic acid from the sn-2 position of mammalian cellular phospholipids. The enzyme consists of a catalytic domain joined to an N-terminal calcium-dependent, membrane binding domain (C2 domain). The interfacial binding properties of the full-length, nonphosphorylated enzyme and its C2 ... More
Exploring a channel to the active site of copper/topaquinone-containing phenylethylamine oxidase by chemical modification and site-specific mutagenesis.
AuthorsMatsuzaki R, Tanizawa K
JournalBiochemistry
PubMed ID9760229
Copper amine oxidase contains an organic redox cofactor, 2,4, 5-trihydroxyphenylalaninequinone (topaquinone, TPQ), derived by the post-translational modification of a specific tyrosyl residue. To identify amino acid residues participating in the biogenesis of TPQ in the recombinant phenylethylamine oxidase from Arthrobacter globiformis, we have modified the copper/TPQ-less apoenzyme and the copper/TPQ-containing ... More
A leucine zipper motif in the ectodomain of Sendai virus fusion protein assembles in solution and in membranes and specifically binds biologically-active peptides and the virus.
AuthorsGhosh JK, Ovadia M, Shai Y
JournalBiochemistry
PubMed ID9398274
We have detected a leucine zipper-like motif in the ectodomain of the Sendai virus fusion protein (aa 269-307) which is extremely conserved in the family of Sendai viruses. To find a possible role for this motif, we synthesized SV-269, a 39 amino acid peptide corresponding to this domain, and a ... More
Sendai virus internal fusion peptide: structural and functional characterization and a plausible mode of viral entry inhibition.
AuthorsGhosh JK, Peisajovich SG, Shai Y
JournalBiochemistry
PubMed ID10995225
Viral glycoproteins catalyze the fusion between viral and cellular membranes. The fusion protein (F(1)) of Sendai virus has two fusion peptides. One is located at its N-terminus and the other, highly homologous to the HIV-1 and RSV fusion peptides, in the interior of the F(1) protein. A synthetic peptide corresponding ... More
Spectrum of antimicrobial activity and assembly of dermaseptin-b and its precursor form in phospholipid membranes.
AuthorsStrahilevitz J, Mor A, Nicolas P, Shai Y
JournalBiochemistry
PubMed ID8086412
Dermaseptins are 27-34 amino acid antimicrobial peptides that irreversibly inhibit growth of pathogenic filamentous fungi, in addition to their ability to inhibit the growth of bacteria, yeasts, and protozoa. Synthetic peptides, with sequences corresponding to dermaseptin-b (DS-b) and its N-terminal extended precursor form dermaseptin-B (DS-B), were synthesized and investigated with ... More
L-aspartate but not the D form is secreted through microvesicle-mediated exocytosis and is sequestered through Na+-dependent transporter in rat pinealocytes.
AuthorsYatsushiro S, Yamada H, Kozaki S, Kumon H, Michibata H, Yamamoto A, Moriyama Y
JournalJ Neurochem
PubMed ID9202328
Rat pinealocytes accumulate glutamate in microvesicles and secrete it through exocytosis so as to transmit signals intercellularly. Glutamate is involved in the negative regulation of norepinephrine-stimulated melatonin production. In this study, we found that aspartate is also released from cultured rat pinealocytes during the exocytosis of glutamate. The release of ... More