カワムラ　クニオ   KAWAMURA Kunio   川村　邦男    所属   広島修道大学  人間環境学部    職種   教授
言語種別	英語
発行・発表の年月	1999/12
形態種別	学術論文
査読	査読有り
標題	Clay catalysis of oligonucleotide formation: Kinetics of the reaction of the 5'-phosphorimidazolides of nucleotides with the non-basic heterocycles uracil and hypoxanthine
執筆形態	共著
掲載誌名	Origins Life Evol. Biosphere
掲載区分	国外
巻・号・頁	29(6),pp.563-591
担当範囲	Corresponding anthor
著者・共著者	◎Kunio Kawamura, J. P. Ferris
概要	The montmorillonite clay catalyzed condensation of activated monocleotides to oligomers of RNA is a possible first step in the formation of the proposed RNA world. The oligomerization reactions of the 5’-phosphoromidazolides of uridine and inosine on montmorillonite yield oligo(U)s and oligo(I)s as long as heptamers. Both the apparent rate constants in the reaction mixture and the rate constants on the clay surface were calculated using the partition coefficients of the oligomers between the aqueous and clay phases. The rate constants for trimer formation are much greater than those dimer synthesis but there was little difference in the rate constants for the formation of trimers and higher oligomers. The overall rates of oligomerization of the phosphorimidazolides of purine and pyrimidine nucleosides in the presence of montmorillonite clay are the same suggesting that RNA formed on the primitive Earth could have contained a variety of heterocyclic bases.