Table 1. Summary of enzyme kinetic of MDH and ICDH from E. coli and S. salinarum.

	Salt or Osmolyte (M)	Km (mM)	Vmax (U mg−1)	Specifity Constant (U mg−1 mM−1)	Osmolyte Performance (Vmax/Km relative to 0.05 M NaCl)
MDHE.coli	0.05 M NaCl	0.022	1,486	67,443	100
	1.2 M NaCl	0.163	227	1,393	2.1
	2.4 M NaCl	0.26	78	306	0.5
	2.5 M GB	0.018	273	15,478	23
MDHS.salinarum	0.05 M NaCl	0.038	2,062	54,832	100
	1.2 M NaCl	0.20	314	1,568	3
	2.4 M NaCl	0.25	144	578	1.1
	2.5 M GB	0.031	519	16,527	30
ICDHE.coli	0.05 M NaCl	0.021	46	2,167	100
	1.2 M NaCl	1.2	12.3	10	0.5
	2.4 M NaCl	3.9	4.7	1.2	0.1
	2.5 M GB	0.009	3.2	369	17
ICDHS.salinarum	0.05 M NaCl	0.019	6.8	353	100
	1.2 M NaCl	0.68	1.6	2.3	0.7
	2.4 M NaCl	0.82	0.32	0.4	0.1
	2.5 M GB	0.014	2.4	170	48

GB, glycine betaine; ICDH, isocitrate dehydrogenase; MDH, malate dehydrogenase; NaCl, sodium chloride.