'Drosophila is an important model organism for investigating neural development, neural morphology, neurophysiology, and neural correlates of behaviors. However, almost nothing is known about how electrical signals propagate in Drosophila neurons. Here, we address these issues in antennal lobe projection neurons, one of the most well studied classes of Drosophila ... More
Enzyme-modulated cleavage of dsDNA for supramolecular design of biosensors.
AuthorsYan F, Sadik OA
JournalAnal Chem
PubMed ID11721929
'Supramolecular docking and immobilization of biotinylated dsDNA onto a self-assembled monolayer of avidin have been measured using impedance spectroscopy and quartz crystal microbalance technique. The formation of the serial assembly was first achieved by linearizing circular plasmid dsDNA using BamH I endonuclease enzyme. This was followed by a bisulfite-catalyzed transamination ... More
Selective labeling of functional groups on membrane proteins or glycoproteins using reactive biotin derivatives and 125I-streptavidin.
AuthorsRoffman E, Meromsky L, Ben-Hur H, Bayer EA, Wilchek M
JournalBiochem Biophys Res Commun
PubMed ID3085669
'Amino groups, sulfhydryl groups or oxidation-induced aldehydes on erythrocyte membrane proteins and/or glycoproteins, were reacted with biotinyl N-hydroxysuccinimide ester (BNHS), 3-(N-maleimido-propionyl) biocytin (MPB) or biocytin hydrazide (BCHZ), respectively. The detergent-lysed biotinylated samples were subjected to SDS-polyacrylamide gel electrophoresis, and the proteins were transferred onto nitrocellulose membranes. The blot was then ... More
Capture of peptides with N-terminal serine and threonine: a sequence-specific chemical method for Peptide mixture simplification.
AuthorsChelius D, Shaler TA
JournalBioconjug Chem
PubMed ID12526710
'The objective of this study was to evaluate a sequence-specific chemistry for the ability to specifically capture peptides that contain N-terminal serine or threonine residues from mixtures. The first step is the oxidation of the 1,2-amino alcohol structure -CH(NH(2))CH(OH)- of peptides containing N-terminal serine or threonine with periodate. The newly ... More
Detection of protein carbonyls by means of biotin hydrazide-streptavidin affinity methods.
AuthorsHensley K,
JournalMethods Mol Biol
PubMed ID19378083
'Oxidative posttranslational protein modifications occur as a normal process of cell biology and to a greater extent during pathogenic conditions. The detection and quantitation of protein oxidation has posed a continuing challenge to bioanalytical chemists because the products of oxidative protein damage are chemically diverse, protein oxidation generally occurs at ... More
The avidin-biotin complex in bioanalytical applications.
AuthorsWilchek M, Bayer EA
JournalAnal Biochem
PubMed ID3044183
Detection of the ganglioside N-glycolyl-neuraminyl-lactosyl-ceramide by biotinylated Escherichia coli K99 lectin.
AuthorsOuadia A, Karamanos Y, Julien R
JournalGlycoconj J
PubMed ID1392562
K99 lectin from Escherichia coli was purified and biotinylated via its carboxyl groups using biocytin hydrazide and a water soluble carbodiimide. Biotinylation of two out of the nine carboxyl groups was sufficient to permit detection of the lectin by avidin and did not cause any loss of the haemagglutinating activity. ... More
Biotinylation reagents for the study of cell surface proteins.
AuthorsElia G,
JournalProteomics
PubMed ID18763706
The extraordinarily stable, non-covalent interaction between avidin and biotin is one of the most commonly exploited tools in chemistry and biology. Methods for derivatization with biotin of a variety of molecules (in particular, proteins) have been introduced, in order to allow their efficient recovery, immobilization and detection with avidin-based reagents. ... More
Lymphocyte activation by oxidative modification: avidin-modified T cells activate biotin-modified autologous T cells but not vice versa.
AuthorsRoffman E, Wilchek M
JournalCell Immunol
PubMed ID3492281
Immunocompetent human thymocytes were oxidized by periodate and conjugated with either biocytin-hydrazide or avidin-hydrazide followed by reduction with borohydride. Without further treatment, the resultant modified cells alone exhibited moderate levels of activation as a function of exogenously added interleukin 2. However, strong interleukin 2-dependent stimulation was observed when avidin-modified cells ... More
Selective covalent modification of newly synthesized activation-induced sialoglycoconjugates on the T lymphocyte membrane.
AuthorsRoffman E, Wilchek M
JournalBiochem Biophys Res Commun
PubMed ID3008722
Resting human lymphocytes were oxidized by periodate and subsequently reduced with borohydride to block the aldehydes formed. The cells were then incubated for 24 or 48 hours with (or without) the mitogenic lectin phytohemagglutinin. A second oxidation with periodate at the indicated times resulted in strong surface-aldehyde formation in samples ... More
Biocytin hydrazide--a selective label for sialic acids, galactose, and other sugars in glycoconjugates using avidin-biotin technology.
AuthorsBayer EA, Ben-Hur H, Wilchek M
JournalAnal Biochem
PubMed ID2456025
Biocytin hydrazide (BCHZ), a new, water-soluble, long-chained, biotin-containing hydrazide, was synthesized and used for the selective nonradioactive detection of glycoconjugates. Procedures were developed for labeling glycoconjugates on blots. The method involves either chemical (periodate-induced) or enzymatic (via galactose oxidase) oxidation of glycoconjugates, the resultant aldehyde groups are then labeled with ... More
Sustained calcium entry through P2X nucleotide receptor channels in human airway epithelial cells.
AuthorsZsembery A, Boyce AT, Liang L, Peti-Peterdi J, Bell PD, Schwiebert EM
JournalJ Biol Chem
PubMed ID12566439
Purinergic receptor stimulation has potential therapeutic effects for cystic fibrosis (CF). Thus, we explored roles for P2Y and P2X receptors in stably increasing [Ca(2+)](i) in human CF (IB3-1) and non-CF (16HBE14o(-)) airway epithelial cells. Cytosolic Ca(2+) was measured by fluorospectrometry using the fluorescent dye Fura-2/AM. Expression of P2X receptor (P2XR) ... More
The extent of oxidative mitogenesis does not correlate with the degree of aldehyde formation of the T lymphocyte membrane.
AuthorsRoffman E, Wilchek M
JournalJ Immunol
PubMed ID3086457
Chemical oxidation of T lymphocytes with periodate or the combined action of the enzymes neuraminidase and galactose oxidase (NAGO) results in T cell activation. The latter process includes the production of interleukin 2 (IL 2) and the induction of IL 2 receptors. Because membrane-bound aldehydes act in the transmission of ... More