Finding of endopolyphosphatase activity in the yeast Saccharomyces cerevisiae.
Endopolyphosphatase activity has been revealed in cytosol preparations of the yeast Saccharomyces cerevisiae with inactivated PPX1 and PPN1 genes encoding exopolyphosphatases. The enzyme cleaves inorganic polyphosphates with chain length of 15 to 208 phosphate residues to shorter chains without the release of orthophosphate (P(i)). The long chain polyphosphates are cleaved with preference over the short ones. Heparin, a known inhibitor of exopolyphosphatases, represses this activity. The endopolyphosphatase activity is not stimulated by Mg(2+) or Co(2+), in contrast to exopolyphosphatases. This activity along with a pyrophosphatase is supposed to be responsible for polyphosphate utilization as a phosphate reserve in a mutant devoid of exopolyphosphatases.
Lichko
L P
LP
Skryabin Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russia. alla@ibpm.pushchino.ru
Kulakovskaya
T V
TV
Kulakovskaya
E V
EV
Kulaev
I S
IS
D017766:Acid Anhydride Hydrolases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004795:Enzyme Stability; D020868:Gene Silencing; D011122:Polyphosphates / Q000737:chemistry / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000737:chemistry / Q000201:enzymology* / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
D011122:Polyphosphates; D029701:Saccharomyces cerevisiae Proteins; D017766:Acid Anhydride Hydrolases; C022563:endopolyphosphatase