Possible Interaction: Cysteine and Papain

“An immunoglobulin IgG (Sackfield) which is known to have polypeptide chains shorter than those of typical proteins of its class has been subjected to fragmentation by papain in the presence of cysteine.”

“Treatment of reduced and alkylated subunits with papain in the presence of cysteine produces Fabu and Fcu fragments.”

“Furthermore, γG2 and γG4 myeloma proteins can be distinguished from each other by their behaviour on incubation with papain in the presence of cysteine (at 37° C, for 4 h).”

“The addition of cysteine to the incubation mixtures of globulins with papain or trypsin enhanced the degree of fragmentation, but some physical and immunochemical properties of these fragments were found to be different from those of fragments obtained in the absence of cysteine.”

“Immobilization of papain on Sepharose 6B in the presence of different concentrations of cysteine affected the enzyme activity depending on cysteine concentration.”

“The maximum specific activity was observed when papain was immobilized with 200 mM cysteine.”

“ Inactive papain reacted with high concentrations of cysteine or cyanide to yield completely repaired active papain, and with benylamine to yield non-repairable, inactive papain.”

“ Papain is reversibly inactivated in the presence of air and low concentrations of cysteine.”