title: Magnesium pyrophosphates in enzyme mimics of nucleotide synthases and kinases and in their prebiotic chemistry.
abstract: Derivatives of ribosyl pyrophosphate have been synthesized, and examined with magnesium salts in the coupling of the ribose unit to various nucleophiles, including pyrazole and 2-chloroimidazole. Only with the magnesium salt present did they generate the ribosyl cation by binding to the leaving group and then couple the ribose derivative with nucleophiles. The role of magnesium salts in phosphorylation of methanol by ATP was also examined. Here a remarkable effect was seen: phosphorylation by ATP was slowed with low concentrations of Mg(2+) but accelerated by higher concentrations. Related effects were also seen in the effect of Mg(2+) on phosphorylation by ADP. The likely mechanisms explain these effects.
authors.affiliation: Department of Chemistry, Columbia University, New York, NY 10027.
authors.forename: Purushothaman
authors.initials: P
authors.lastname: Gopinath
authors.affiliation: Department of Chemistry, Columbia University, New York, NY 10027.
authors.forename: Vijayakumar
authors.initials: V
authors.lastname: Ramalingam
authors.affiliation: Department of Chemistry, Columbia University, New York, NY 10027 rb33@columbia.edu.
authors.forename: Ronald
authors.initials: R
authors.lastname: Breslow
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism*; D011756:Diphosphates / Q000378:metabolism*; D017616:Magnesium Compounds / Q000378:metabolism*; D000432:Methanol / Q000378:metabolism; D018716:Molecular Mimicry; D015394:Molecular Structure; D009711:Nucleotides / Q000096:biosynthesis*; D000069497:Origin of Life; D010766:Phosphorylation / Q000502:physiology*; D012266:Ribose / Q000378:metabolism
chemical_list: D011756:Diphosphates; D017616:Magnesium Compounds; D009711:Nucleotides; D012266:Ribose; D000255:Adenosine Triphosphate; C034732:magnesium pyrophosphate; D000432:Methanol
keywords: ADP; ATP; nucleosides; phosphoribosyl pyrophosphate