[methionine synthase] reductase (NADPH) activity
[methionine synthase] reductase (nadph) activity
Catalysis of the reaction: [methionine synthase]-cob(II)alamin + NADPH + H+ + S-adenosyl methionine = [methionine synthase]-methylcob(I)alamin + S-adenosylhomocysteine + NADP+.