TABLE 2.

Specific activities and binding affinities for HCB of wild-type HcbA1 and its mutants

Category	Protein	Sp act (μmol/min·g)	KD (M) for HCB
Wild type	HcbA1	8.26 ± 0.67	1.0 × 10−12
Active mutant	H17A	2.55 ± 0.19	2.2 × 10−7
	M12A	4.87 ± 0.54	1.8 × 10−7
Inactive mutant	R311L		1.8 × 10−5
	R314L		4.5 × 10−5
	H79A		2.0 × 10−5
	V59A		8.6 × 10−5
	F10A		2.1 × 10−4
Insoluble mutant	Y362S
	Y362F
	D315A