1.5.1.5	C58Y	kcat/Km for 5,10-methenyltetrahydrofolate is 8.4fold lower than wild-type value	
1.5.1.5	D121A	kcat/Km for 5,10-methenyltetrahydrofolate is 600fold lower than wild-type value	
1.5.1.5	D133E	mutant retains no dehydrogenase activity	
1.5.1.5	D133E	no dehydrogenase activity retained, Mg2+ binding site	
1.5.1.5	G122D	kcat/Km for 5,10-methenyltetrahydrofolate is 84fold lower than wild-type value	
1.5.1.5	K54S	kcat/Km for 5,10-methenyltetrahydrofolate is identical to wild-type value	
1.5.1.5	K56Q/Q100K	retaines two-third of dehydrogenase activity but no cyclohydrolase activity	
1.5.1.5	K56Q/Q100K	site-directed mutagenesis shows that the double mutant has no cyclohydrolase activity but retains two-thirds of the normal dehydrogenase activity	
1.5.1.5	additional information	asparagine-125 is required for folate-substrate binding, arginine-173 mutation causes 500fold increase in the Km for NADP, serine-197 mutation a 20fold increase	
1.5.1.5	additional information	knockout mutant of MTHFD2 is embryonic lethal in mice at about 12 days gestation, no normal development of hematogenesis in the liver	
1.5.1.5	additional information	mutation of arginine-166 leads to complete loss of dehydrogenase activity, is critically responsible for binding of the inorganic phosphate, with arginine-198 mutation some dehydrogenase activity is retained, it probably only assists in phosphate binding	
1.5.1.5	additional information	successful double replacement of the DHCH1 gene is a result of double electroporation with two replacement fragments but an intact gene copy is retained (probably aneuploidy), additional metabolic complementation to bypass the requirement for DHCH1 is not successful either, ectopic addition of DHCH1 or formate-tetrahydrofolate ligase before the second replacement step finally results in a null mutant without chromosomal DHCH1 gene (dhch1-/pXNG4-DHCH1 or dhch1-/pXNG4-FTL) or addition to wild-type in overexpressing transfectants (WT/pXNG4-DHCH1 or WT/pXNG4-FTL)	
1.5.1.5	Q98K	very low activity with 5,10-methenyltetrahydrofolate	
1.5.1.5	R191E	very low activity with 5,10-methenyltetrahydrofolate	
1.5.1.5	R653Q	mutant enzyme has normal substrate affinity but a 36% reduction in half-life at 42°C	
1.5.1.5	Y50S	very low activity with 5,10-methenyltetrahydrofolate