A + choline = AH2 + betaine aldehyde Amine and polyamine biosynthesis; betaine biosynthesis via choline pathway; betaine aldehyde from choline (cytochrome c reductase route): step 1/1. Acetylation of Lys-498 is observed in liver mitochondria from fasted mice but not from fed mice. Decreased testicular betaine and increased choline and phosphatidylcholine concentrations. Only one of eleven males was able to reproduce, impaired fertility was due to diminished sperm motility. Belongs to the GMC oxidoreductase family.