Substitution of lysine at position 104 or 240 of TEM-1 sub(pTZ18R) beta -lactamase enhances the effect of serine-164 substitution on hydrolysis or affinity for cephalosporins and the monobactam aztreonam

• Published in: Biochemistry (Easton) Vol. 30; no. 13; pp. 3179 - 3188
• Main Authors: Sowek, JA, Singer, S B, Ohringer, S, Malley, M F, Dougherty, T J, Gougoutas, J Z, Bush, K
• Format: Journal Article
• Language: English
• Published: 01.01.1991
• Subjects: lysine; serine

By site-directed mutagenesis, TEM-1 beta -lactamase was altered to contain single amino acid changes of E104K, R164S, and E240K, in addition to double changes of E104K/R164S or R164S/E240K and the triple changes of E104K/R164S/E240K. Hydrolysis rates for cephaloridine and benzylpenicillin were lower...