The present study intended to verify activities of cysteine proteinase of Pneumocystis carinii from rats and to purify the enzyme. In order to exclude the contamination of host-derived enzymes, concentrates of P. carinii was primarily treated with a mixture of proteinase inhibitors before lysis of P. carinii. A 68-kDa cysteine proteinase was finally purified from the crude extract of P. carinii...

The interaction ae-macroglobulin with four proteinases has been investigated by binding assays and by gel electrophoresis. At pH 7.65 the binding ratios of the proteinase-cwa-macroglobulin complexes were found to be 2:l (trypsin and papain), 1.4:1 (chymotrypsin), and 1:l (plasmin). The progressive decrease in the stoichiometry of the three seryl proteinase complexes was paralleled by a concomit...

In the nanomolar enzyme and inhibitor concentration range, 1 mol of mucus proteinase inhibitor (MPI) inhibits 1 mol of neutrophil elastase, cathepsin G, trypsin, and chymotrypsin. In the micromolar concentration range, the enzyme:inhibitor binding stoichiometry is still 1:1 for elastase but shifts to 2:1 for the three other proteinases. These data could be confirmed by three nonenzymatic method...

The interaction of the 56-kilodalton (kDa) proteinase from Serratia marcescens with human plasma activated C1 (C1) inhibitor, alpha 2-antiplasmin, and antithrombin III was investigated. The 56-kDa proteinase was not affected by these inhibitors; on the contrary, all the inhibitors were inactivated by the 56-kDa proteinase within 2 to 6 h. Sodium dodecyl sulfate-polyacrylamide gel electrophoresi...

Proteinase inhibitors play an important role in plant resistance of insects and pathogens. In this study, we characterized the serine proteinase inhibitor SaPIN2b, which is constitutively expressed in Solanum americanum trichomes and contains two conserved motifs of the proteinase inhibitor II (PIN2) family. The recombinant SaPIN2b (rSaPIN2b), which was expressed in Escherichia coli, was demons...

Male Sprague-Dawley rats that received 60% total body surface, full-thickness, scald burns on the dorsum and abdomen were used in this study. Neutral proteinase and Ca2+-activated neutral proteinase activities were measured in gastrocnemius and soleus muscles at 3 and 21 days after the thermal injury. Neutral proteinase activity decreased significantly in the soleus (50%) and gastrocnemius (46%...

The NIa proteinase from pepper vein banding virus (PVBV) is a sequence-specific proteinase required for processing of viral polyprotein in the cytoplasm. It accumulates in the nucleus of the infected plant cell and forms inclusion bodies. The function of this protein in the nucleus is not clear. The purified recombinant NIa proteinase was active, and the mutation of the catalytic residues His-4...

Previous work has indicated a crucial role for the extracellular cysteine proteinase of Streptococcus pyogenes in the pathogenicity and virulence of this important human pathogen. Here we find that the purified streptococcal cysteine proteinase releases biologically active kinins from their purified precursor protein, H-kininogen, in vitro, and from kininogens present in the human plasma, ex vi...

The capacity for self-polymerization and shape of the tubulin polymers assembled after digestion with trypsin, Pronase, chymotrypsin, subtilisin, Staphylococcus aureus proteinase V8 and proteinase K were investigated. Digestion with trypsin, Pronase or chymotrypsin resulted in a decrease in the ability of tubulin for self-assembly, whereas limited proteolysis with subtilisin, S. aureus proteina...

Activation of inflammatory pathways is known to accompany development of obesity-induced non-alcoholic fatty liver disease (NAFLD), insulin resistance and type 2 diabetes. In addition to caspase-1, the neutrophil serine proteases proteinase 3, neutrophil elastase and cathepsin G are able to process the inactive pro-inflammatory mediators IL-1β and IL-18 to their bioactive forms, thereby regulat...