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Abstract
Humans, as well as other mammals, must convert ingested vitamin B12 to active coenzyme forms for biologic activity. We found that human fibroblasts in
tissue culture are capable of carrying out this conversion and we report a method
to measure the accumulation of newly synthesized coenzymes by the cultured cells.
Fibroblasts are grown in culture medium which contains the precursor vitamin, 57Co-hydroxocobalamin. After 4 days the cells are harvested. Cobalamins are extracted
from the cells and then separated by thin layer chromatography. In addition to the
hydroxocobalamin, two peaks of radioactivity are found which correspond to the coenzyme
forms of B12, deoxyadenosylcobalamin and methylcobalamin. The ability to study coenzyme synthesis
and accumulation in human cells will enable investigation of normal B12 metabolism and of human disease states where abnormal metabolism is suspected.
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References
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Article info
Publication history
Accepted:
May 12,
1971
Received:
February 15,
1971
Footnotes
☆Supported by research grants from the John A. Hartford Foundation and the National Institutes of Health (AM 12579).
Identification
Copyright
© 1971 Published by Elsevier Inc.
