TABLE 5.

Relative hydrolytic activity (with 100 μM nitrocefin) of Gly238 β-lactamase mutants

aa variationa	RHA (μM/s/mg of protein)b
Gly (wt)	281.3
Ala	20.8
Ser	4.34
Cys	0
Pro	0.64
Asp	4.2
Thr	13.8
Asn	28.9
Val	9.4
Glu	37.5
Gln	37.8
His	12.6
Ile	13.7
Leu	0.9
Met	38.5
Lys	16.0
Phe	7.2
Tyr	2.3
Arg	8.8
Trp	1.5

^aaa, amino acid; wt, wild type.

^bRHA, relative hydrolytic activity (±10% error). The mean of three independent determinations is given.