Culture of Rhizobium cobalaminogenum capable of producing vitamin B12 and mutants thereof

摘要

There is provided an economical, efficient and industrially useful method of producing vitamin B12 which comprises cultivating a microorganism belonging to Rhizobium cobalaminogenum which is capable of producing vitamin B12 in a culture medium to produce vitamin B12 and recovering the produced vitamin B12. There are also provided a microorganism belonging to Rhizobium cobalaminogenum which is capable of producing vitamin B12 and a microorganism Rhizobium cobalaminogenum 27B74 (FERM BP-4429).