Author(s)

Nadezhda Andreeva¹, Ludmila Trilisenko¹, Mikhail Eldarov², Tatiana Kulakovskaya^1*

¹Skryabin Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, Pushchino, Russia.
²Institute of Bioengineering, Centre of Biotechnology, Russian Academy of Sciences, Moscow, Russia.

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.

Polyphosphate, Yeast, PPN1, Polyphosphatase, Deoxyadenosine Triphosphate Phos-phohydrolase, dATP

Andreeva, N. , Trilisenko, L. , Eldarov, M. and Kulakovskaya, T. (2016) Polyphosphatase PPN1 of Saccharomyces cerevisiae Is a Deoxyadenosine Triphosphate Phosphohydrolase. Advances in Enzyme Research, 4, 144-151. doi: 10.4236/aer.2016.44013.