We have investigated the effect of protease inhibitors on hyperthermic cell killing using cultured mammalian cells (L5178Y) and found that protease inhibitors were potent hyperthermia sensitizers. At 37 degrees C, phenylmethylsulfonyl fluoride (PMSF), a serine protease inhibitor, was not cytotoxic at the concentration of 400 micrograms/ml for up to 6 h. When cells were exposed to PMSF (200-400 ...

Calpastatin is an endogenous inhibitor of calpain (calcium-dependent cysteine protease). Calpastatin activityis highly related to the rate of protein turnover and rate of meat tenderization. In order to characterize thestructure of calpastatin in Iranian Afshari breed of sheep, intron 6 and partial exon 7 of the L domain wereamplified and sequenced. A fragment of approximately...

The transcriptome response of Tribolium castaneum larvae to dietary protease inhibitors was evaluated by whole-genome microarray analysis. RNA was isolated from guts of larvae fed control diet (no inhibitor), or diets containing 0.1% E-64 (cysteine protease inhibitor), 5.0% soybean trypsin inhibitor (STI, serine protease inhibitor), or a combination of 0.1% E-64 and 5.0% STI. Data were analyzed...

Human protein C inhibitor (PCI), a serpin-type protease inhibitor originally described as an inhibitor of activated protein C, has broad protease reactivity. In addition to its activities within the blood clotting and fibrinolytic cascades, it seems to participate in several biological processes including reproduction and tumor growth. This review summarizes the current understanding of PCI fun...

Although many human immunodeficiency virus type 1 (HIV-1)-infected persons are treated with multiple protease inhibitors in combination or in succession, mutation patterns of protease isolates from these persons have not been characterized. We collected and analyzed 2,244 subtype B HIV-1 isolates from 1,919 persons with different protease inhibitor experiences: 1,004 isolates from untreated per...

The effect of solid-phase fibrin on the inactivation of plasmin, miniplasmin, and neutrophil leukocyte elastase (PMN-elastase) by plasma protease inhibitors (alpha 2-antiplasmin, alpha 1-protease inhibitor, alpha 2-macroglobulin) was studied. In Hanks' balanced salt solution, fibrin reduces the second-order rate constant for the inhibition of PMN-elastase by alpha 1-protease inhibitor from 8,76...

Protease K1 activity initiates the degradation of the Kunitz soybean trypsin inhibitor (KSTI) during germination and early seedling growth. This enzyme was purified nearly 1300-fold from the cotyledons of 4-day-old soybean (Glycine max [L.] Merrill) seedlings. Protease K1 is a cysteine protease with a molecular weight of approximately 29,000. It cleaves the native form of KSTI, Ti(a), to Ti(a) ...

A protease inhibitor unsticks cells AI-1 is unique among protease inhibitors because it binds to the matrix protein vitronectin (VN). PAI-1 binding blocks VN's binding site for the cell surface receptor uPAR and for integrin family members. Czekay et al. (page 781) now show that PAI-1 is also able to detach cells through a less direct approach. Unlike the direct competition method, PAI-1 also d...

It has already been reported that muscle necrosis induced by various phenylenediamine derivatives are correlated with their autoxidation rate. Now in a more detailed investigation of the cytotoxic mechanism using a model system of isolated hepatocytes and ring-methylated structural isomer durenediamine (DD) we have shown that under aerobic conditions, phenylenediamine induced cytotoxicity and R...