Studies on the biosynthesis of vitamin B sub 2 and vitamin B sub 12
Abstract
Feeding experiments with Ashbya gossypii followed by NMR analysis of the resulting riboflavin showed incorporation of deuterium from D-(2-{sup 2}H)ribose at C-2{prime} and from D-(1-{sup 2}H)ribose in the pro-R position at C-1{prime} of the ribityl side chain. The results rule out an Amadori rearrangement mechanism for the reduction of the ribosylamino to the ribitylamino linkage and point to formation of a Schiff base that is reduced stereospecifically opposite to the face from which the oxygen has departed. As prerequisite for the analysis, the {sup 1}H NMR signals for the pro-R and pro-S hydrogens at C-1{prime} of riboflavin and its tetraacetate were assigned with the aid of synthetic stereospecifically deuteriated samples. Feeding experiments with Propionibacterium shermianii followed by NMR analysis of the resulting vitamin B{sub 12} showed: (1) 5-methylbenzimidazole (5MBI) incorporated and only one regioisomer (B6-demethylcyanocobalamin)formed. (2) 8-demethylriboflavin incorporated and the same regioisomer was obtained as 5MBI experiment. (3) (1{prime}-{sup 13}C, 5-{sup 15}N)riboflavin incorporated and {sup 13}C-NMR showed that {sup 13}C at the B2 position of cyanocobalamin coupled to both adjacent nitrogen-15 atoms at about the same ratio.
- Authors:
- Publication Date:
- Research Org.:
- Ohio State Univ., Columbus, OH (USA)
- OSTI Identifier:
- 7165272
- Resource Type:
- Thesis/Dissertation
- Resource Relation:
- Other Information: Thesis (Ph. D.)
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 59 BASIC BIOLOGICAL SCIENCES; VITAMIN B GROUP; BIOSYNTHESIS; VITAMIN B-12; BACTERIA; CARBON 13; DEUTERIUM; NITROGEN 15; NMR SPECTRA; SCHIFF BASES; TRACER TECHNIQUES; CARBON ISOTOPES; DRUGS; EVEN-ODD NUCLEI; HEMATINICS; HEMATOLOGIC AGENTS; HYDROGEN ISOTOPES; IMINES; ISOTOPE APPLICATIONS; ISOTOPES; LIGHT NUCLEI; MICROORGANISMS; NITROGEN ISOTOPES; NUCLEI; ODD-EVEN NUCLEI; ODD-ODD NUCLEI; ORGANIC COMPOUNDS; ORGANIC NITROGEN COMPOUNDS; SPECTRA; STABLE ISOTOPES; SYNTHESIS; VITAMINS; 550201* - Biochemistry- Tracer Techniques
Citation Formats
Chen, H C. Studies on the biosynthesis of vitamin B sub 2 and vitamin B sub 12. United States: N. p., 1988.
Web.
Chen, H C. Studies on the biosynthesis of vitamin B sub 2 and vitamin B sub 12. United States.
Chen, H C. 1988.
"Studies on the biosynthesis of vitamin B sub 2 and vitamin B sub 12". United States.
@article{osti_7165272,
title = {Studies on the biosynthesis of vitamin B sub 2 and vitamin B sub 12},
author = {Chen, H C},
abstractNote = {Feeding experiments with Ashbya gossypii followed by NMR analysis of the resulting riboflavin showed incorporation of deuterium from D-(2-{sup 2}H)ribose at C-2{prime} and from D-(1-{sup 2}H)ribose in the pro-R position at C-1{prime} of the ribityl side chain. The results rule out an Amadori rearrangement mechanism for the reduction of the ribosylamino to the ribitylamino linkage and point to formation of a Schiff base that is reduced stereospecifically opposite to the face from which the oxygen has departed. As prerequisite for the analysis, the {sup 1}H NMR signals for the pro-R and pro-S hydrogens at C-1{prime} of riboflavin and its tetraacetate were assigned with the aid of synthetic stereospecifically deuteriated samples. Feeding experiments with Propionibacterium shermianii followed by NMR analysis of the resulting vitamin B{sub 12} showed: (1) 5-methylbenzimidazole (5MBI) incorporated and only one regioisomer (B6-demethylcyanocobalamin)formed. (2) 8-demethylriboflavin incorporated and the same regioisomer was obtained as 5MBI experiment. (3) (1{prime}-{sup 13}C, 5-{sup 15}N)riboflavin incorporated and {sup 13}C-NMR showed that {sup 13}C at the B2 position of cyanocobalamin coupled to both adjacent nitrogen-15 atoms at about the same ratio.},
doi = {},
url = {https://www.osti.gov/biblio/7165272},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Jan 01 00:00:00 EST 1988},
month = {Fri Jan 01 00:00:00 EST 1988}
}