A COENZYME CONTAINING PSEUDOVITAMIN B 12

Abstract
The isolation of a coenzyme form of pseudovitamin B12 is reported which is required for the decomposition of glutamate by particle-free extracts of Clostridium tetanomorphum. The coenzyme is involved in the rearrangement of the C skeleton of glutamate to form a branched-chain amino acid, [beta]-methylaspartate. Chemical analysis indicates the coenzyme contains one or more purine moieties. The light-sensitivity of the coenzyme and the large shift of the peak in the visible region to longer wave lengths on exposure to light suggest that a functionally important substituent group is attached both to C and to some part of the conjugated double-bond system of the prophyrin-like structure.