Binding of Cob(II)alamin to the adenosylcobalamin-dependent ribonucleotide reductase from Lactobacillus leichmannii. Identification of dimethylbenzimidazole as the axial ligand

Autor:	C C, Lawrence, G J, Gerfen, V, Samano, R, Nitsche, M J, Robins, J, Rétey, J, Stubbe
Rok vydání:	1999
Předmět:	Lactobacillus Vitamin B 12 Deoxycytosine Nucleotides Ribonucleotide Reductases Electron Spin Resonance Spectroscopy Benzimidazoles Cobamides Enzyme Inhibitors Ligands Catalysis Protein Binding
Zdroj:	The Journal of biological chemistry. 274(11)
ISSN:	0021-9258
Popis:	The ribonucleoside triphosphate reductase (RTPR) from Lactobacillus leichmannii catalyzes the reduction of nucleoside 5'-triphosphates to 2'-deoxynucleoside 5'-triphosphates and uses coenzyme B12, adenosylcobalamin (AdoCbl), as a cofactor. Use of a mechanism-based inhibitor, 2'-deoxy-2'-methylenecytidine 5'-triphosphate, and isotopically labeled RTPR and AdoCbl in conjunction with EPR spectroscopy has allowed identification of the lower axial ligand of cob(II)alamin when bound to RTPR. In common with the AdoCbl-dependent enzymes catalyzing irreversible heteroatom migrations and in contrast to the enzymes catalyzing reversible carbon skeleton rearrangements, the dimethylbenzimidazole moiety of the cofactor is not displaced by a protein histidine upon binding to RTPR.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=pmid________::1f4f5f0bdd81ff25922d3a26a29c06af https://pubmed.ncbi.nlm.nih.gov/10066759 Zobrazit plný text záznamu