Papain inhibitory activity in normal & cataractous mammalian lenses
Chandrasekher, G.; Virupaksha, H.S.; Pattabiraman, T.N.
Indian Journal of Medical Research 82: 458-462
1985
ISSN/ISBN: 0019-5340 PMID: 4093164 Document Number: 259555
Papain inhibitory activity was observed in human, sheep, goat and bovine lenses. The activity (absorbance units/mg protein, mean .+-. SD) was more in human (infant 0.32 .+-. 0.07; adult 0.28 .+-. 0.05) lenses than in animal lenses (bovine 0.09 .+-. 0.01; goat 0.13 .+-. 0.04; sheep 0.13 .+-. 0.03). Inhibitory activity when expressed as a function of lens weight was found to decrease with age (human adults 96.7 .+-. 24.7; infants 129 .+-. 29.5) and during cataractogenes (human cataract lenses (75.2 .+-. 20.0). The trend of insolubilization of proteins with age and cataractogenesis was also reflected in the case of the inhibitory activity. The inhibitory activity was markedly increased on heat treatment (80.degree. C, 10 min) suggesting the presence of thiol proteases and inhibitors in lenticular tissue.