LAWRENCE J. BRANDT, M.D.; LESLIE H. BERNSTEIN, M.D.; WAGLE ABDUL, M.S.
We investigated the presence of vitamin B12 analogues (cobamides) and the bacterial conversion of 57Co-B12 (vitamin B12 cyanocobalamin, [57Co]-CN-Cbl) into cobamides in the intestinal contents of four patients with bacterial overgrowth. The (57Co)-CN-Cbl bound to intrinsic factor was given orally. Jejunal contents were aspirated for 24 h and cultured aerobically and anaerobically. The CN-Cbl and cobamides were separated by electrophoresis and chromatography and identified by bioautography. Radioactivity of cobamide zones from duplicate chromatograms showed bacterial conversion of (57Co)-CN-Cbl into cobamides. Cobamides ([AdeJCNCba, [2-Me Ade] CNCba, [CN]2Cbi and factor E) were found in the intestinal contents in three of the four patients, and in two of three patients cobamides represented more than 25% of the administered CN-Cbl. Thus bacterial production of cobamides, both de novo and from ingested CN-Cbl bound to intrinsic factor, occurs in humans with bacterial overgrowth states and results in a significant loss of vitamin B12 to the host.
BRANDT LJ, BERNSTEIN LH, ABDUL W. Production of Vitamin B12 Analogues in Patients with Small-Bowel Bacterial Overgrowth. Ann Intern Med. ;87:546–551. doi: 10.7326/0003-4819-87-5-546
Download citation file:
Published: Ann Intern Med. 1977;87(5):546-551.
Results provided by:
Copyright © 2019 American College of Physicians. All Rights Reserved.
Print ISSN: 0003-4819 | Online ISSN: 1539-3704
Conditions of Use