Effects of Protease from Plerocercoid of Spirometra erinacei on Host Structural Protein.

点击翻译按钮获取中文摘要

Thiol protease was isolated from plerocercoid of Spirometra erinacei (plerocercoid protease, pl-p). Splitting activities of the protease against structural and contractile proteins from host vertebrate skeletal muscle were investigated. the results obtained are as follows.1) Pl-P may cleave native actin and myosin peptides. G-actin is digested by pl-p more quickly than F-actin. ATPase activity remained intact on the residues produced by myosin digestion.2) A myofibril prepared from host skeletal muscle, having macromolecular structure may also digested by pl-p in vitro. myosin, a constituent of the thick-filament on, myofibril, is splitted and dissolved without a loss of its ATPase activity.3) Effects of pl-p on the host actomyosin containing a regulatory system (myosin-B) were examined by changes in superprecipitation as an in vitro model of muscular contraction. Ca^<2+>-sensitivity in the actomyosin system is lost by the addition of pl-p.4) The effect of pl-p on regulatory proteins, tropomyosin and troponin was examined. Substrates used are cleaved more preferably cleaved by pl-p in the following order: troponin T-subunit<greater than or equal> troponin I-subunit > tropomyosin > troponin CResults obtained from the present study suggest that pl-p from S. erinacei plerocercoids may be able to degradate host muscular structure.