title: [Vitamin B 12 dependent methionine biosynthesis in pseudomonas aeruginosa].
abstract: Among methionineless mutants of Pseudomonas aeruginosa strain PAO lacking the ability of methylating homocysteine we found two different types: One of them responding to methionine only, the other one to methionine or vitamin B12 alternatively. That means that P. aeruginosa PAO as well as other B12-producing bacteria (with one exception: Aerobacter aerogenes) use only the B12 pathway (metH) for methionine synthesis. The effect of some cys-auxotrophs equally growing on vitamin B12 as described by Calhoun and Feary (1969) was confirmed for P. aeruginosa PAO by our mutants. In a P. aeruginosa strain of other origin, PAE, neither met- nor cys-mutants responding to B12 have been found, although strain PAE as well as strain PAO excessively synthesize B12.
mesh_terms: D003545:Cysteine / Q000378:metabolism; D006710:Homocysteine / Q000378:metabolism; D008715:Methionine / Q000096:biosynthesis* / Q000378:metabolism; D008769:Methylnitronitrosoguanidine; D009153:Mutagens; D011550:Pseudomonas aeruginosa / Q000254:growth & development / Q000378:metabolism*; D013237:Stereoisomerism; D014805:Vitamin B 12 / Q000378:metabolism*
chemical_list: D009153:Mutagens; D006710:Homocysteine; D008769:Methylnitronitrosoguanidine; D008715:Methionine; D003545:Cysteine; D014805:Vitamin B 12
vernacular_title: Vitamin B12-ABHANGIGE Methioninbiosynthese bei Pseudomonas aeruginosa