Exploration of a pho13 knockout growth phenotype in non‐engineered strains of Saccharomyces cerevisiae

Abstract

Pho13p from Saccharomyces cerevisiae (budding yeast) is a member of the Haloacid Dehalogenase (HAD) superfamily. Accumulating evidence indicates a loss of Pho13p function imparts an enhanced ability of engineered strains to grow on D‐xylose. Recent evidence has also indicated that Pho13p exhibits specificity towards the substrate 2‐phosphoglycolate but a growth phenotype in non‐engineered pho13 deletion strains has not been apparent. There is evidence that 2‐phosphoglycolate is generated by yeast pyruvate kinase (PYK1) as a secondary metabolic reaction and that fructose‐1,6‐bisphosphate accelerates this activity. The accumulation of 2‐phosphoglycolate under these conditions could impart a growth phenotype in pho13 deletion cells as 2‐phosphoglycolate inhibits triose phosphate isomerase (TPI1). Non‐engineered strains of yeast were subjected to the metabolic inhibitors pyrazole and 2‐thenoyltrifluoroacetone (TTA) that have been shown to increase fructose‐1,6‐bisphosphate in cells. Mutant pho13 deletion strains did not exhibit any hypersensitivity to these inhibitors under rich growth conditions. Currently, pho13 deletion strains are being examined using minimal growth media in combination with pyrazole and TTA. The yeast pyruvate kinase open reading frame is also being PCR‐amplified from genomic DNA and cloned under the control of the GAL1 promoter to assess whether overexpression could enhance a potential inhibitor effect.Support or Funding InformationThis work was supported by an internal NTID FEAD grant (A.U.G.)This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.