Isolation,
heterological cloning and sequencing of the PEL1/PGS1 gene from Kluyveromyces
lactis.
Margita Obernauerova, Silvia Tyciakova, Lucia Dokusova, Kamila Peterkova, Julius
Subik
Dep. Microbiology and Virology, Comenius University, Mlynska dolina B-2,
Bratislava, 842 15, Slovak Republic (obernauerova@fns.uniba.sk)
The PEL1 gene encodes a phosphatidylglycerolphosphate synthase, the enzyme which catalyses the first step in the biosynthesis of cardiolipin. Pel1p is localized to the inner mitochondrial membrane. Mutations in the PEL1 gene have been found to convert the petite-positive strain Saccharomyces cerevisiae to petite-negative one. Kluyveromyces lactis is a petite-negative yeast species and the integrity of mitochondrial genome is required for the viability of its cells, like for the pel1 mutant in S. cerevisiae. The present work is focused to the isolation, cloning and characterization of the PEL1 homologue from K. lactis. The pel1 mutant strain of S. cerevisiae was used to isolate this homologue by screening K. lactis genomic library. The new gene was named KlPGS1. This gene was assigned to chromosome I. Its coding region was found to consist of 1623 bp. The corresponding protein exhibits 57% identity to the S. cerevisiae counterpart. A mitochondrial targeting presequence of Kl-Pel1p is longer than that of Sc-Pel1p. The authors thank Ben J. Zonneveld for the K. lactis genomic library. This work was supported by grants from Slovak Grant Agency of Science, from Complutense University, Madrid and from the Slovak Ministry of Education.