IMPROVED METHOD FOR THE PRODUCTION OF VITAMIN B12

摘要

The invention relates to an improved method for producing vitamin B12, according to which a culture containing a microorganism in which at least the enzymes uroporphyrinogen-III-methyltransferase and precorrin-2-dehydrogenase that are involved in sirohaem synthesis have an increased activity as opposed to the corresponding endogenous enzyme activities is fermented.