Abstract
X factor isolated from a bacterial cell preparation is cobinamide, or a closely related compound. Its addition to the culture medium together with dimethylbenzimidazole resulted in a marked increase in cobamide production by P. Shermanii, a cobamide-producing organism. The highest value obtained under optimum condition was as high as 5 μg/ml, a yield not very high in view of industrial production, but considering the fact that the cobamide production by P. Shermanii IAM 1713 used by the authors is not very high, producing insignificant cobamide in the medium of Bernhauer devoid of cobalt salts. The pronounced increase in cobamide production after addition of X factor and DBI seems to suggest both compounds to be the precursors. One of the purpose of the authors is to identify the form of cobamide produced and the yield of the cobamide may be sufficient for such study.
