TABLE 3.

Affinity constants (K_m) for cystathionine-γ-synthase (MetB) and cystathonine-β-lyase (MetC) from C. glutamicum (this study) and from data for other bacteria and a plant taken from the literature

Enzyme	Substrate	Km (μM) (organism or plant)	References
Cystathionine-γ-synthase	l-Cysteine	260 (C. glutamicum)	This study
	l-Cysteine	180 (Spinach)	24
	l-Cysteine	50 (E. coli)	7
	l-Homocysteine	540 (C. glutamicum)	This study
Cystathionine-β-lyase	l-Cystathionine	110 (C. glutamicum)	This study
	l-Cystathionine	40 (E. coli)	2
	l-Cystathionine	220 (Serovar Typhimuriuma)	2
	l-Cystathionine	70 (Bordetella avium)	5
	l-Homolanthionine	4,540 (E. coli)	2

^aSalmonella enterica serovar Typhimurium.