title: Modification of amino groups in porcine pancreatic elastase with polyethylene glycol in relation to binding ability towards anti-serum and to enzymic activity.
abstract: Porcine pancreatic elastase was modified by activated polyethylene glycol (2-0-methoxy-polyethyleneglycol-4, 6-dichloro-s-triazine) with molecular weight of 5000. The modification of elastase in which three amino groups out of the total four amino groups in the molecular gave rise to a complete loss of the binding ability towards anti-elastase serum from rabbit. The modified enzyme showed 35% of the original enzymic activity towards succinyl-L-alanyl-L-alanyl-L-alanine-p-nitroanilide and 17% towards casein. The heat-denatured collagen was also digested by the modified elastase, but the enzymic activity towards the elastin substrate was completely lost. The inhibition of the modified elastase activity by alpha 2-macroglobulin was found to be lesser than that of non-modified elastase.
mesh_terms: D000818:Animals; D003094:Collagen / Q000378:metabolism; D004549:Elastin / Q000378:metabolism; D006358:Hot Temperature; D007106:Immune Sera; D008970:Molecular Weight; D010179:Pancreas / Q000201:enzymology*; D010196:Pancreatic Elastase / Q000378:metabolism*; D011092:Polyethylene Glycols / Q000378:metabolism*; D013329:Structure-Activity Relationship; D013552:Swine
chemical_list: D007106:Immune Sera; D011092:Polyethylene Glycols; D003094:Collagen; D004549:Elastin; D010196:Pancreatic Elastase