Stress Resistance of Saccharomyces cerevisiae Strains Overexpressing Yeast Polyphosphatases

Nadeshda Andreeva,Ludmila Trilisenko,Larisa Ledova,Lubov Ryazanova,Tatiana Kulakovskaya

doi:10.3390/stresses2010002

Abstract

Inorganic polyphosphate (polyP) is an important factor in the stress resistance of microorganisms. The polyphosphate-overexpressing strains of yeast S. cerevisiae were used as a model for studying the inter-relationship between stress resistance and polyP level. We compared the polyP level and resistance to the oxidative, manganese, cadmium, and alkaline stresses in parent stain CRN and in strains overexpressing the four yeast polyphosphatases: Ppx1, Ppn1, Ppn2, and Ddp1. Strains overexpressing Ppx1, Ppn1, and Ppn2 have lower polyP content and the strain overexpressing Ddp1 has the same polyP content as the parent strain. The strains overexpressing Ppn1 and Ddp1 show higher resistance to peroxide and manganese. The strain overexpressing Ppx1 showed a decrease in peroxide resistance. The strain overexpressing Ppn2 was more resistant to alkaline and peroxide stresses. A similar increase in resistance to the manganese and peroxide stresses of strains overexpressing Ppn1 and Ddp1, which differ in polyP content, led to the conclusion that there is no direct relationship between polyP content and variations in this resistance. Thus, we speculate about the potential role of inositol pyrophosphates as signaling molecules in stress response.

Highlights

Inorganic polyphosphate, a linear polymer containing a few to several hundred orthophosphate residues, participates in various processes regulating vital activities [1,2,3,4], including stress response in microbial cells [1,5,6,7,8,9]
PolyP and polyphosphate kinases are involved in the induction of the synthesis of RpoS, an RNA polymerase subunit in bacteria that provides the expression of the genes responsible for adaptation to the stationary stage and are necessary for bacterial cell motility, biofilm formation, and virulence [1]
We demonstrated that the overexpression of yeast polyphosphatases in the cells of S. cerevisiae alters their stress resistance, independently of changes in polyP content

Summary

Introduction

Inorganic polyphosphate (polyP), a linear polymer containing a few to several hundred orthophosphate residues, participates in various processes regulating vital activities [1,2,3,4], including stress response in microbial cells [1,5,6,7,8,9]. In the cells of radioresistant bacterium Deinococcus radiodurans, the PPKDr gene encoding polyphosphate kinase and the PPXDr gene encoding Mn-dependent polyphosphatase exhibited different expression profiles under oxidative stress [15]. Stresses 2022, 2 upregulated and polyphosphatase hydrolyzed polyP-Mn, followed by phosphate (Pi) release and Mn–Pi formation [16]. Hf tehnecpe,atrheinst sstutrdayincaonmdpfaoruesr rsetrsaisintasnocevetroexopxirdesastiivneg, paloklaylpinheo,sapnhdathaeseasvyPpmxe1t,aPl pstnr1e,ssPepsno2f, tahnedpDardepn1t , sctrualtinivaatnedd fuonudresrttrhaeinssamoveecruexltpurreescsoinngdiptioolnysp, hinocslpuhdaintagsegsroPwptxh1s, tPagpen1a,nPdpPni2c,oanncdenDtrdatpio1n,

Strains and Growth Conditions

Pi and polyP Extraction and Assay

Polyphosphatase Activity Assay

Findings

Conclusions