Polyphosphatase PPN1 of Saccharomyces cerevisiae Is a Deoxyadenosine Triphosphate Phosphohydrolase  

作　　者：Nadezhda Andreeva Ludmila Trilisenko Mikhail Eldarov Tatiana Kulakovskaya Nadezhda Andreeva;Ludmila Trilisenko;Mikhail Eldarov;Tatiana Kulakovskaya(Skryabin Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, Pushchino, Russia;Institute of Bioengineering, Centre of Biotechnology, Russian Academy of Sciences, Moscow, Russia)

机构地区：[1]Skryabin Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, Pushchino, Russia [2]Institute of Bioengineering, Centre of Biotechnology, Russian Academy of Sciences, Moscow, Russia

出　　处：《Advances in Enzyme Research》2016年第4期144-151,共9页酶研究进展（英文）

摘　　要：The Saccharomyces cerevisiae polyphosphatase PPN1 (uniprot/Q04119) degrades inorganic polyphosphates both by cleaving Pi from the chain end and by fragmenting long-chain polymers into shorter ones. In this study, we have found a new activity of this protein: it releases phosphate from dATP. The dATP phosphohydrolase activity of pure PPN1 was ~7-fold lower compared to the exopolyphosphatase activity. This activity was strongly stimulated by Co²⁺ ions, as well as by ammonium ions, and inhibited by heparin and pyrophosphate similar to the exopolyphosphatase activity of PPN1. The Km value for dATP was 0.88 ± 0.14 mM. The dATP phosphohydrolase activity in the cells of PPN1-overexpressing yeast strain was several-fold higher than that in the parent strain. The other exopolyphosphatase of S. cerevisiae, PPX1, did not split Pi from dATP.The Saccharomyces cerevisiae polyphosphatase PPN1 (uniprot/Q04119) degrades inorganic polyphosphates both by cleaving Pi from the chain end and by fragmenting long-chain polymers into shorter ones. In this study, we have found a new activity of this protein: it releases phosphate from dATP. The dATP phosphohydrolase activity of pure PPN1 was ~7-fold lower compared to the exopolyphosphatase activity. This activity was strongly stimulated by Co²⁺ ions, as well as by ammonium ions, and inhibited by heparin and pyrophosphate similar to the exopolyphosphatase activity of PPN1. The Km value for dATP was 0.88 ± 0.14 mM. The dATP phosphohydrolase activity in the cells of PPN1-overexpressing yeast strain was several-fold higher than that in the parent strain. The other exopolyphosphatase of S. cerevisiae, PPX1, did not split Pi from dATP.

关 键 词：POLYPHOSPHATE YEAST PPN1 Polyphosphatase Deoxyadenosine Triphosphate Phos-phohydrolase dATP 

分 类 号：O63[理学—高分子化学]