Carboxybiotin translocation mechanisms suggested by diffraction studies of biotin and its vitamers.
- 1 January 1980
- journal article
- research article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences
- Vol. 77 (1) , 333-337
- https://doi.org/10.1073/pnas.77.1.333
Abstract
Biotin is a coenzyme that fixes CO2 for transfer in a family of carboxylase, decarboxylase and transcarboxylase enzymes. Their enzyme reactions involve 2 basic steps during which a carboxybiotinyl intermediate forms at 1 site and translocates to a 2nd (distinct) site for CO2 transfer. Diffraction studies of biotin and its vitamers suggest that translocation involves rotation about 1, or at most 2, bonds in biotin''s valeryl chain. The rotations are energetically economical gauche .dblarw. trans rotations about the 2 valeryl bonds nearest the biotin bicyclic ring. They move a C atom of a CO2 moiety bound at N-1'' approximately 7 .ANG., a distance in accord with spectroscopic measurements of 1 of the biotin enzymes. S in biotin may impart to the valeryl chain a conformational variability necessary for bond rotation and, hence, translocation between catalytic sites.This publication has 10 references indexed in Scilit:
- The contribution of microchemical methods of histochemistry to the biological sciences.Journal of Histochemistry & Cytochemistry, 1977
- The crystal and molecular structure of (+–)-azabiotin hydrochloride monohydrate, the nitrogen analog of biotinActa Crystallographica Section B: Structural Science, Crystal Engineering and Materials, 1977
- Crystal and molecular structure of d,l-dethiobiotin. Role of sulfur in biotin stereochemistryJournal of the American Chemical Society, 1976
- Molecular structure of biotin. Results of two independent crystal structure investigationsJournal of the American Chemical Society, 1976
- Magnetic resonance studies of the proximity and spatial arrangement of propionyl coenzyme A and pyruvate on a biotin-metalloenzyme, transcarboxylaseBiochemistry, 1976
- Proton and phosphorus-31 Fourier transform magnetic resonance studies of the conformation of enzyme-bound propionyl coenzyme A on transcarboxylaseBiochemistry, 1976
- Electron and nuclear magnetic resonance studies of the interaction of pyruvate with transcarboxylaseBiochemistry, 1974
- Synthesis and Growth-Promoting Activity of dl-cis-Hexahydro-4-( 4-carboxybutyl)-2-cyclopentimidazolone: CarbobiotinJournal of Pharmaceutical Sciences, 1972
- Transcarboxylase. VI. Kinetic analysis of the reaction mechanism.1969
- Structure of the Bis-p-bromoanilide of Carbon Dioxide Biotin*Biochemistry, 1965