Quenched BODIPY dye-labeled casein substrates for the assay of protease activity by direct fluorescence measurement.
AuthorsJones LJ, Upson RH, Haugland RP, Panchuk-Voloshina N, Zhou M, Haugland RP
JournalAnal Biochem
PubMed ID9299009
'We have prepared casein conjugates of two BODIPY dyes for use as fluorogenic protease substrates in homogeneous assays. Both conjugates are labeled to such an extent that the dyes are efficiently quenched in the protein, yielding virtually nonfluorescent substrate molecules. These fluorogenic substrates release highly fluorescent BODIPY dye-labeled peptides upon ... More
'Many areas of research today are based on enzymatic assays most of which are still performed as enzyme-linked immunosorbent assays in microtiter plates. The demand for highly parallel screening of thousands of samples eventually led to a miniaturization and automation of these assays. However, the final transfer of enzymatic assays ... More
Continuous assay of proteases using a microtiter plate fluorescence reader.
AuthorsMenges DA, Ternullo DL, Tan-Wilson AL, Gal S
JournalAnal Biochem
PubMed ID9398357
A protease-dependent mechanism for initiating T-dependent B cell responses to large particulate antigens.
AuthorsCatron DM, Pape KA, Fife BT, van Rooijen N, Jenkins MK,
JournalJ Immunol
PubMed ID20208013
Ab production is critical for antimicrobial immunity, and the initial step in this process is the binding of Ag to the BCR. It has been shown that small soluble proteins can directly access the lymph node follicles to reach naive B cells, but virus particles must be translocated into follicles ... More
Selective modulation of superantigen-induced responses by streptococcal cysteine protease.
AuthorsKansal RG, Nizet V, Jeng A, Chuang WJ, Kotb M
JournalJ Infect Dis
PubMed ID12552423
Streptococcal pyrogenic exotoxin (Spe) B, a streptococcal cysteine protease, is believed to be important in group A streptococcal (GAS) pathogenesis. The present study examined the effect of SpeB on the activity of superantigenic exotoxins secreted by M1T1 GAS isolates. The proliferative response of human lymphocytes to culture supernatant (SUP) from ... More
Probing the cathepsin D using a BODIPY FL-pepstatin A: applications in fluorescence polarization and microscopy.
AuthorsChen CS, Chen WN, Zhou M, Arttamangkul S, Haugland RP
JournalJ Biochem Biophys Methods
PubMed ID10737220
Redistribution of cathepsin D, a major lysosomal aspartic endopeptidase, has been related to various pathological progressions during tumor formation and oxidation stress. We have synthesized a fluorescent probe for cathepsin D, where the pepstatin A was covalently conjugated with the BODIPY (Boron dipyrromethene difluoride) fluorophore. In vitro, BODIPY FL-pepstatin A ... More
Proteinase assay by capillary electrophoresis employing fluorescence-quenched protein-dye conjugates.
AuthorsWelder F, McCorquodale EM, Colyer CL
JournalElectrophoresis
PubMed ID12179975
Determination of proteinases--enzymes that catalyze the hydrolysis of peptide bonds--is often difficult due to the presence of interferences in complex biological media and limited sample size. Capillary electrophoresis (CE), with laser-induced fluorescence (LIF) can serve as a useful tool for such determinations. LIF detection offers the advantages of increased sensitivity ... More
Directed polar secretion of protease from single cells of Vibrio cholerae via the type II secretion pathway.
AuthorsScott ME, Dossani ZY, Sandkvist M
JournalProc Natl Acad Sci U S A
PubMed ID11698663
Bacteria have long been thought of as little more than sacks of homogeneously distributed enzymes. However, recent cytological studies indicate that bacteria are compartmentalized with proteins involved in processes such as cell division, motility, chemotaxis, and development located at distinct sites. We have used the green fluorescent protein as a ... More
Inverse relation between disease severity and expression of the streptococcal cysteine protease, SpeB, among clonal M1T1 isolates recovered from invasive group A streptococcal infection cases.
AuthorsKansal RG, McGeer A, Low DE, Norrby-Teglund A, Kotb M
JournalInfect Immun
PubMed ID11035746
The streptococcal cysteine protease (SpeB) is one of the major virulence factors produced by group A streptococci (GAS). In this study we investigated if differences exist in SpeB production by clonally related M1T1 clinical isolates derived from patients with invasive infections. Twenty-nine of these isolates were from nonsevere cases and ... More