Easily reversible desthiobiotin binding to streptavidin, avidin, and other biotin-binding proteins: uses for protein labeling, detection, and isolation.
AuthorsHirsch JD, Eslamizar L, Filanoski BJ, Malekzadeh N, Haugland RP, Beechem JM, Haugland RP
JournalAnal Biochem
PubMed ID12419349
'The high-affinity binding of biotin to avidin, streptavidin, and related proteins has been exploited for decades. However, a disadvantage of the biotin/biotin-binding protein interaction is that it is essentially irreversible under physiological conditions. Desthiobiotin is a biotin analogue that binds less tightly to biotin-binding proteins and is easily displaced by ... More
Insights into the mechanism of pore opening of acid-sensing ion channel 1a.
'Acid-sensing ion channels (ASICs) are trimeric cation channels that undergo activation and desensitization in response to extracellular acidification. The underlying mechanism coupling proton binding in the extracellular region to pore gating is unknown. Here we probed the reactivity toward methanethiosulfonate (MTS) reagents of channels with cysteine-substituted residues in the outer ... More
S-glutathiolation by peroxynitrite of p21ras at cysteine-118 mediates its direct activation and downstream signaling in endothelial cells.
AuthorsClavreul N, Adachi T, Pimental DR, Ido Y, Schöneich C, Cohen RA
JournalFASEB J
PubMed ID16415107
'The highly reactive species, peroxynitrite, is produced in endothelial cells in pathological states in which the production of superoxide anion and NO is increased. Here, we show that peroxynitrite added exogenously or generated endogenously in response to exposure to an NO donor or oxidized low-density lipoproteins (oxLDL) increases p21ras activity ... More
Isoform-specific regulation of Akt by PDGF-induced reactive oxygen species.
AuthorsWani R, Qian J, Yin L, Bechtold E, King SB, Poole LB, Paek E, Tsang AW, Furdui CM,
JournalProc Natl Acad Sci U S A
PubMed ID21670275
'Isoform-specific signaling of Akt, a major signaling hub and a prominent therapeutic target, remained poorly defined until recently. Subcellular distribution, tissue-specific expression, substrate specificity, and posttranslational modifications are believed to underlie isoform-specific signaling of Akt. The studies reported here show inhibition of Akt2 activity under physiologically relevant conditions of oxidation ... More
Beta-lactam antibiotics modulate T-cell functions and gene expression via covalent binding to cellular albumin.
AuthorsMor F, Cohen IR,
JournalProc Natl Acad Sci U S A
PubMed ID23382225
Recent work has suggested that beta-lactam antibiotics might directly affect eukaryotic cellular functions. Here, we studied the effects of commonly used beta-lactam antibiotics on rodent and human T cells in vitro and in vivo on T-cell-mediated experimental autoimmune diseases. We now report that experimental autoimmune encephalomyelitis and adjuvant arthritis were ... More
LC-MS/MS analysis of apical and basolateral plasma membranes of rat renal collecting duct cells.
AuthorsYu MJ, Pisitkun T, Wang G, Shen RF, Knepper MA,
JournalMol Cell Proteomics
PubMed ID16899541
We used biotinylation and streptavidin affinity chromatography to label and enrich proteins from apical and basolateral membranes of rat kidney inner medullary collecting ducts (IMCDs) prior to LC-MS/MS protein identification. To enrich apical membrane proteins and bound peripheral membrane proteins, IMCDs were perfusion-labeled with primary amine-reactive biotinylation reagents at 2 ... More
S-glutathionylation impairs signal transducer and activator of transcription 3 activation and signaling.
AuthorsXie Y, Kole S, Precht P, Pazin MJ, Bernier M,
JournalEndocrinology
PubMed ID18988672
S-glutathionylation is a physiological, reversible protein modification of cysteine residues with glutathione in response to mild oxidative stress. Because the key cell growth regulator signal transducer and activator of transcription (STAT) 3 is particularly susceptible to redox regulation, we hypothesized that oxidative modification of cysteine residues of STAT3 by S-glutathionylation ... More
Immobilized nitro-avidin and nitro-streptavidin as reusable affinity matrices for application in avidin-biotin technology.
AuthorsMorag E, Bayer EA, Wilchek M
JournalAnal Biochem
PubMed ID8954558
Chemically modified forms of egg-white avidin and bacterial streptavidin (termed nitro-avidin and nitro-streptavidin, respectively), in which the binding-site tyrosine was nitrated, were used for several biotechnological applications. The fundamental difference between nitro-avidin and the native protein is that interaction of the modified protein with biotin can be reversed under relatively ... More