Trypsin-like protease

This signal peptide might have been eliminated by a trypsin-like protease cleavage (Benoist et al., 1987) since an Arg occurs in the CLPGl sequence, as in the case of PG of F. momUfonne and of PGII of A. niger (Bussink et al., 1991 Caprari et al., 1993). 

Bromomethyl-3,4-dibromo-3,4-dihydrocoumarin 1 (Fig. 11.4) and its chloro-methylated analogue 2b rapidly and progressively inactivate a-chymotrypsin and also the activities of a series of trypsin-like proteases. A benzyl substituent characteristic of good substrates of a-chymotrypsin was introduced at the 3-position to make inhibition more selective. This substituted dihydrocoumarin 3 irreversibly inhibited a-chymotrypsin and other proteases. These functionalized six-membered aromatic lactones, and their five- and seven-membered counterparts, 3//-benzofuran-2-ones 2a26 and 4,5-dihydro-3//-benzo[b]oxepin-2-ones 2c,27 were the first efficient suicide inhibitors of serine proteases. Their postulated mechanism of action is shown in Scheme 11.2. 

It is generally believed that proteases enhance cancer spread primarily by catalyzing degradation of the extracellular matrix. Since multiple substrates are encountered in this matrix, a number of different proteases are likely to be required to complete the metastatic process. Multiple proteases may also be required to activate different inactive precursor forms. Thus, in vitro, plasmin (D7), cathepsin B (D7), and a trypsin-like protease (K12) can all activate pro-uPA, while plasmin, which results from the action of uPA on plasminogen, can activate certain metalloproteases (M4). As mentioned earlier, completion of the metastatic process may require a cascade of different proteases operating, as shown in Fig. 2. 

Minhas T and Greenman J (1989) Production of cell-bound and vesicle-associated trypsin-like protease, alkaline phosphatase and N-acetyl—glucosaminidase by Bacteroides gingivalis strain W50. J Gen Microbiol 135, 557-564. 

St Leger et al. (1987b) characterized two subtilisin-like proteases (chymoelastases) and three tiypsin-like proteases from M. anisopliae. A subtilisin-like protease (Prl pl=10.3, Mw=25 kDa) and a trypsin-like protease (Pr2 pl=4.42, Mw=28.5 kDa) were purified to homogeneity. Inhibition studies have revealed that both enzymes possess essential Ser and His residues in the active site. Prl exhibited higher activity to locust cuticle than Pr2 and it showed activity to elastin as well. 

Pei et al. (2000) purified MAP-21, a further cuticle-degrading serine protease from M. anisopliae. Fungal cultures were induced by minimal medium supplemented with Cicada exuviae, colloidal chitin, shrimp cuticle, maggot cuticle, horsefly cuticle and silkworm Chrysalis cuticle. The recognition site of the protease occurred to be Arg. Studies with different protease inhibitors have revealed that MAP-21 is a trypsin-like protease. 

The inducibility of Prl by proteinaceous compounds released enzymatically from insect cuticle was also studied inM anisopliae (Paterson et al., 1994b). In the case of Schistocerca gregaria cuticle treated with KOH in order to remove proteins, no induction of Prl production was observed, while cuticle treated with chloroform or ether to remove lipids was able to induce enzyme production. Digestion of cuticle with Prl or the trypsin-like protease Pr2 ofM anisopliae resulted in peptides mainly in the range of 150-2000 Da. The addition of these peptides at 3 pg Ala equivalents ml"1 led to the induction of Prl production to a level (75%) similar to that observed in the case of untreated insect cuticle. The ability of various amino acids and peptides abundant in insect cuticular protein (Ala, Gly, Ala-Ala, Ala-Ala-Ala, Ala-Pro and Pro-Ala) to induce Prl was tested but none of them was found to increase enzyme production in the levels observed with cuticle, or peptides enzymatically released from the cuticle. 

The regulation of the trypsin-like protease Pr2 of M anisopliae was examined by Paterson et al. (1993). Three insoluble protein sources, insect cuticle, elastin and collagen, as well as two soluble proteins, gelatine and especially bovine serum albumin (BSA) were found... 

Mohanty et al. (2008) studied the efficacy of the virulent M. anisopliae strain 892 -isolated from Pyrausta nubilalis - against mosquito larvae. LC50 values of M. anisopliae 892 for Culex quinquefasciatus, Anopheles stephensi and Aedes aegypti were examined. M. anisopliae 892 was found to cause approximately 50% mortality of C. quinquefasciatus 4 days post inoculation. The production of subtilisin-like (Prl) and trypsin-like protease (Pr2) was measured in the presence of certain inducers. Significant differences in the production of Prl and Pr2 were found following the addition of inducers i.e. cuticles of the three... 

Paterson, I. C., Chamley, A. K., Cooper, R. M., and Clarkson J. M. (1993). Regulation of production of a trypsin-like protease by the insect pathogenic fungus Metarhizium anisopliae. FEMSMicrobiology Letters, 109, 323-328. 

Thrombin is the pivotal trypsin-like protease for the regulation of thrombosis and hemostasis. Thrombin hydrolyzes its natural substrates by recognition of the Pro-Arg motif in the apolar S2- and the primary specificity SI pocket [42]. The molecular structure of the thrombin-CtA complex (Figure 1.11) showed that CtA was bound to the active site of the enzyme. The arginine side chain formed an electrostatic interaction with Aspl89, located at the bottom of the SI binding pocket. 

Note that proteolysis in conjunction with ion-exchangers may be used in special cases. The pH used with anion exchangers (typically around 8) may induce the activation of proteases such as trypsin-like proteases as well as plasmin and kallikrein when traces are present (these come from animal sera). In this case DEAE and Q, ion-exchangers should therefore be avoided as the first separation chromatographic column. 

Often-cited examples for tandem duplications are pepsin, a member of the aspartate protease family [19], and chymotrypsin, representative of the trypsin-like protease family [20], Structurally, both enzymes consist of two homologous, stacked domains, fi-... 

Diphtheria toxin is produced as a single polypeptide chain (Fig. la) yyhich is easily cleaved ("nicked") by trypsin and trypsin-like proteases into two disulfide-linked fragments, A and B (Pappenheimer, 1977). The structure of the nicked toxin resembles that of the plant toxins ricin, abrin, modeccin, viscumin and others (Olsnes and Sandvig, 1985). 

Inaba, K., C.C. Buerano, F.F. Natividad and M. Morisawa. Degradation of vitellogenins by 170 kDa trypsin-like protease in the plasma of the tilapia, Oreochromis niloticus. Comp. Biochem. Physiol. 118B 85-90, 1997. 

Substituted (i.e. C (NH)NH2, halogen, N02 etc.) benzylphenyl ethers, a,(ji)-dioxyalkanes and a,a, a"-tris(phenoxy) mesitylene benzamidines have been synthesized and analyzed for their inhibition of boar acrosin, a trypsin-like protease in spermatozoa. 2 of the compounds are more... 

Assay of the isozymers from L rubellus is based on the enzymic reaction with various substrates. F-T and F-III are thought to represent a chymotrypsin-like and a trypsin-like protease, respectively [24], F-II appears to act as a trypsin-like protease or an elastase. Interestingly, F-II1-1 and -2, also with strong caseinolylic activity, have much higher fibrinolytic activity than plasmin as described by Mihara et al. [1,3]... 

Mono- and diamidlnobenzimidazoles such as bis(5-amidino-2-benzimldazolyDmethane (BABIM) (jO) possess significant suppressive effects on the cytopathology and yield of respiratory syncytial virus (RSV). 7 The mechanism of action of BABIM may be related to its inhibition of certain trypsin-like proteases, 7 but a study of twenty-four amidlne derivatives showed no correlation between RSV-lnduced cell fusion and inhibition of four protease enzymes. 8... 

Affinity chromatographic purification of a trypsin-like protease from 375 Streptomyces griseus... 

Bdelllns a group of protease inhibitors from leeches. Particularly high activities of B. are found in the region of the outer sex organs and in the salivary glands of the leech, Hirudo medicinalis. B. inhibit trypsin and plasmin, and they show strong inhibition of the trypsin-like protease, acrosin, present in the ac-rosomes of spermatozoa. 

The proteasome inhibitors salinosporamide A and omuralide are both y-lactam-p-lactone bicy-clic compounds (Fig. 13.5) derived from natural sources. Salinosporamide A, also known as marizomib, is obtained from Salinospora tropica, a bacterium found in ocean sediments. The drug is an irreversible proteasome inhibitor that shows little effect on the caspase-like activity but inhibits chymotrypsin- and trypsin-like protease activities. Preclinical studies have demonstrated antitumor activity in models for multiple myeloma, hematologic malignancies, and solid tumors and, importantly, marizomib does not show cross-resistance with other proteasome inhibitors. Omuralide (clasto-lactacystin p-lactone p-clastolactacystin) is the active metabolite of... 

The parasporal crystalline inclusion bodies formed within the B. thuringiensis cells adjacent to the endospore during spomlation are protoxins which are composed of precursors of the active 5-endotoxins and DNA (Clarimont et al., 1998). For the three conventional three-domain toxins, e.g. Cryl, Cry2 and Cry3, the C-terminal half of these inactive protoxins are enzymatically cleaved within the midgut of susceptible insect larvae by trypsin-like proteases to the active toxin, which consists of the N-terminal portion of the molecule (Federici, 1993 Rukmini et al., 1999). 

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