The coordinating properties of d-biotin.
The coenzyme d-biotin offers in its anionic form to metal ions 3 possible binding sites: the carboxylate group of the valerate side chain, the ureido residue of the 2-imidazolidone ring, and the thioether sulfur of the tetrahydrothiophene ring; the coordinating properties of these groups are summarized and compared. Hydrogen bond formation of the ureido group has also been observed, and hydrogen bonding may possibly be important in biotin-bicarbonate recognition. The aliphatic part of the valeric acid side chain can undergo hydrophobic interactions. Such interactions and/or the stereoselective sulfur-metal ion coordination could be the means for a correct 'fixation' of the biotinyl moiety at the surface of a protein, thus creating the active enzyme-substrate complex.
D001665:Binding Sites; D001710:Biotin / Q000378:metabolism*; D002264:Carboxylic Acids / Q000378:metabolism; D002413:Cations, Divalent; D055598:Chemical Phenomena; D002621:Chemistry; D003300:Copper / Q000378:metabolism; D004355:Drug Stability; D006860:Hydrogen Bonding; D008345:Manganese / Q000378:metabolism; D008670:Metals / Q000378:metabolism; D008968:Molecular Conformation; D013440:Sulfides / Q000378:metabolism; D015032:Zinc / Q000378:metabolism
D002264:Carboxylic Acids; D002413:Cations, Divalent; D008670:Metals; D013440:Sulfides; D008345:Manganese; D001710:Biotin; D003300:Copper; D015032:Zinc