CHYMOSTATIN

Description

Chymostatin is a bioactive peptide of microbial origin that acts as a protease inhibitor with selectivity for chymotryptase-like serine proteases. It potently inhibits chymotrypsin and chymase (K_i = 9.36 and 13.1 nM, respectively) while less effectively blocking the activity of cathepsins, papain, and leukocyte elastase. It is without effect on trypsin, thrombin, plasmin, pepsin, and kallikrein.

The Uses of CHYMOSTATIN

Chymostatin is a specific inhibitor of α-, β-, γ-, and δ-chymotrypsin.

The Uses of CHYMOSTATIN

Chymostatin has been used in a study that determined that molecular calculations are useful for evaluating the interactions between ligands, including inhibitors and homologous enzymes, in docking models. Chymostatin has also been used in a study to investigate the norovirus protease as an attractive target for antiviral drug development.

What are the applications of Application

Chymostatin is an inhibitor of chymotrypsin, papain, and cathepsin G, A, B, H, and L

General Description

Chymostatin is a mixture of three components, A, B, and C. The component A being N-[((S)-1-carboxy-2-phenylethyl)-carbamoyl]-α-[2-iminohexahydro-4(S)-pyrimidyl]-L-glycyl-L-leucyl-phenylalaninal. The other two components B and C differ in that the L-leucyl residue is substituted by L-valine and L-isoleucine, respectively.

Biochem/physiol Actions

Chymostatin is a strong inhibitor of many proteases, including chymotrypsin, papain, chymotrypsin-like serine proteinases, chymases, and lysosomal cysteine proteinases such as cathepsins A,B,C, B, H, and L. It weakly inhibits human leucocyte elastase. It is effective at a final concentration of 100 to 200 μg/ml (10 to 100 μM). Chymostatin is often included in protease inhibitor cocktails used with plant extracts.

in vitro

chymostatin was found to be a potent inhibitor of human leucocyte chymotrypsin-like protease. its affinity to the leucocyte protease was found to be much higher than its affinity to bovine pancreatic alpha-chymotrypsin. chymsotatin also showed a weak inhibitory effect on the activity of human leucocyte elastase. in addition, the preincubation of chymostatin with 35so2-4-labeled cartilage before the addition of the human chymotrypsin-like protease to the tissue could also inhibit 35so2-4 release [1].

in vivo

the effect of chymostatin on c57bl/6j-dy dystrophic mice was studied. the locomotor activity of normal mice markedly increased, attaining a plateau at 8 weeks of age. serum levels of creatine phosphokinase were much higher in dystrophic mice when compared with normal mice, and dystrophic mice also showed a reduced muscle protein content. when 3-week-old dystrophic mice received chymostatin at 1 mg/kg, the decrease in locomotor activity could be retarded, serum enzyme levels significantly decreased, and muscle protein content also obviously increased. in addition, the survival time of chymostatin-treated dystrophic mice was prolonged [2].

References

1) Umezawa?et al.?(1970),?Chymostatin, a new chymotrypsin inhibitor produced by actinomycetes; J. Antibiot. (Tokyo)?23?425 2) Johnson?et al.?(1998),?Inactivation of chymotrypsin and human skin chymase: kinetics of time-dependent inhibition in the presence of substrate; Biochim. Biophys. Acta?953?269 3) Stein and Strimpler (1987),?Slow-binding of chymotrypsin and cathepsin G by the peptide aldehyde chymostatin; Biochemistry?26?2611 4) Roszkowska-Chojecka?et al.?(2015),?Effects of chymostatin, a chymase inhibitor, on blood pressure, plasma and tissue angiotensin II, renal haemodynamics and renal excretion in two models of hypertension in the rat; Exp. Physiol.?100?1093