Two glyoxylate reductase isoforms are functionally redundant but required under high photorespiration conditions in rice

Table 3 K_m and V_max of OsGR1 and OsGR2 with various substrates

Enzyme	Substrate at fixed concentration	Substrate at varying concentration	K_m (μM)	V_max (μmol glyoxylate min⁻¹ mg⁻¹ protein)
OsGR1	Glyoxylate	NADPH	17.6 ± 3.1	74.7 ± 5.9
	NADPH	Glyoxylate	30.4 ± 3.5	74.7 ± 5.9
	Glyoxylate	NADH	420.2 ± 50.5	59.9 ± 8.1
	NADH	Glyoxylate	267.7 ± 22.7	59.9 ± 8.1
OsGR2	Glyoxylate	NADPH	53.0 ± 4.6	61.9 ± 3.2
	NADPH	Glyoxylate	72.1 ± 5.3	61.9 ± 3.2
	Glyoxylate	NADH	403.9 ± 66.5	22.4 ± 3.5
	NADH	Glyoxylate	144.6 ± 19.3	22.4 ± 3.5

The OsGR1 and OsGR2 expressed in E.coli were purified for analyses, and K_m values with different substrate pairs were compared. Values are means ± SD (n = 3)