The effect of amino acid substitution at position 219 of Citrobacter freundii cephalosporinase on extension of its substrate spectrum
K Tsukamoto, R Ohno, M Nukaga, T Sawai
Eur J Biochem
207
3
DOI: 10.1111/j.1432-1033.1992.tb17150.x
PMID: 1499556