Open AccessDisruption of phospholipase B gene, PLB1 , increases the survival of baker's yeast Torulaspora delbrueckii
Author(s) -
Watanabe Yasuo,
Imai Kenji,
Oishi Hideki,
Tamai Youichi
Publication year - 1996
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1996.tb08609.x
Subject(s) - gene , biology , genetics , chemistry , ecology
An uracil auxotrophic mutant of baker's yeast Torulaspora delbrueckii , which is resitant to 5‐fluoro‐orotic acid, was complemented by transformation with YEp24 which harbors 2 μm origin and URA3 derived from Saccharomyces cerevisiae . The phospholipase B in T. delbrueckii cells is active in both acidic and alkaline conditions. However, activity of phospholipase B gene ( PLB1 ) in cells of disruption mutant ( plbI : : URA3 ) was lost in both conditions, which indicates that all phospholipase B activity is encoded by a single gene (or a single polypeptide) in these yeast cells. Over‐expression of PLB1 with YEp plasmid vector in T. delbrueckii cells showed ∼ 2.5‐fold increase in phospholipase B activity, comparing with that in wild‐type cells. Cells of plb1 Δ mutant showed increased survival when cells of plb1 Δ mutant and wild‐type strain were incubated in water at 30 °C. Cells of PLB1 ‐over‐expressed strain died rapidly even during the cultivation period, indicating that phospholipase B activity may be a determinant for the survival of this yeast.