Rapid evolution of recombinant Saccharomyces cerevisiae for Xylose fermentation through formation of extra-chromosomal circular DNA.

ABSTRACT: Circular DNA elements are involved in genome plasticity, particularly of tandem repeats. However, amplifications of DNA segments in Saccharomyces cerevisiae reported so far involve pre-existing repetitive sequences such as ribosomal DNA, Ty elements and Long Terminal Repeats (LTRs). Here, we report the generation of an eccDNA, (extrachromosomal circular DNA element) in a region without any repetitive sequences during an adaptive evolution experiment. We performed whole genome sequence comparison between an efficient D-xylose fermenting yeast strain developed by metabolic and evolutionary engineering, and its parent industrial strain. We found that the heterologous gene XylA that had been inserted close to an ARS sequence in the parent strain has been amplified about 9 fold in both alleles

SUBMITTER: Demeke MM 

PROVIDER: S-EPMC4352087 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature