Table 1.

The specific activity of GEO1900 and AF0933 toward different keto acids.

Amino acceptor	Specific activity (U/mg)
	GEO1900a	AF0933b
3-methyl-2-oxobutyrate	n.a.	5.14
4-methyl-2-oxopentanoate	7.7	3.05
3-methyl-2-oxopentanoate	7.1	3.23
2-oxopentanoate	n.a.	6.51
2-oxohexanoate	n.a.	4.26
2-oxooctanoate	n.a.	2.4
2-oxobutyrate	1.3	n.a.
pyruvate	0.56	0.73
phenylglyoxylate	n.a.	4.55
β-phenylpyruvate	n.a.	2.84
indole-3-pyruvate	n.a.	1.02

^a5 mM L-glutamate was used as the amino donor and 5 mM keto acid was used at 65°C in 50 mM phosphate buffer, pH 8.0; supplemented with 60 μM PLP.

^b10 mM L-glutamate was used as the amino donor and 10 mM keto acid was used at 70°C in 100 mM Tris-HCl buffer pH 7.5 supplemented with 0.1 mM PLP.

Not all donor acceptor pairs were tested for both enzymes.