Defects in Auxiliary Redox Proteins Lead to Functional Methionine Synthase Deficiency (original) (raw)

Methionine synthase, essential for methionine synthesis, requires redox activation, which has been poorly understood in mammals. This research identifies that mammalian methionine synthase can be activated through an NADPH-dependent pathway and necessitates the involvement of at least two redox proteins. Through biochemical complementation studies involving cblG and cblE cell lines, it was determined that defects in these cell lines have distinct impacts on methionine synthase function—cblG illustrates direct defects in the enzyme, while cblE highlights abnormalities in the redox proteins, underscoring the complexities of cobalamin-dependent metabolic pathways.