Fig. 6

Identification of the causative gene GAS1 on chromosome XIII by using reciprocal hemizygosity analysis of candidate alleles of low pH resistance phenotype. A Spot growth assay of the hemizygous diploids for GAS1, ELP6, GLC8, and FET4. The reciprocal hemizygote containing the GAS1 allele from ACY503 outperformed the one presenting the allele of CEN.PK113-1A(CEN.PK) at pH 2.1. Spot growth assay on control condition (pH 6) was also performed to check if hemizygous deletion did not affect strain fitness. B Spot assay on low pH of ACY503 and CEN.PK113-1A (CEN.PK) strains with interchanged GAS1 allele. The swap of GAS1 allele between the strains remarkably improved CEN.PK113-1A tolerance to low pH, while the opposite occurred with ACY503 expressing GAS1 allele from CEN.PK113-1A