Kinetics of the reversible reaction of papain with 5,5'-dithiobis-(2-nitrobenzoate) dianion: evidence for nucleophilic reactivity in the un-ionized thiol group of cysteine-25 and for general acid catalysis by histidine-159 of the reaction of the 5-mercapto-2-nitrobenzoate dianion with the papain-5-mercapto-2-nitrobenzoate mixed disulphide.
Source:http://linkedlifedata.com/resource/pubmed/id/5084801
