ENHANCED GLYCOSYLATION USING MODIFIED ENDOHEXOSAMINIDASE

摘要

Replacement of the key glutamic acid 173 residue of Endo A by either glutamine or histidine produces mutant enzymes for which hydrolytic activity has either been eliminated, or significantly curtailed, yet which still effect transglycosylation of acceptor substrates by the use of oxazolines as glycosyl donors. The E173H histidine mutant was demonstrated to be more effective than wild type Endo A for the production of a single homogenous glycoform of ribonuclease B.