Organization of specific genomic regions of Zygosaccharomyces rouxii and Pichia sorbitophila:: comparison with Saccharomyces cerevisiae

The genomes of Zygosaccharomyces rouxii and Pichia sorbitophila were partially explored. The genome of Z. rouxii CBS 732 consists of seven chromosomes with an approximate size of 1.0-2.75 Mb, 12.8 Mb in total, Five of the chromosomes were labelled with specific probes, Three Z. rouxii genomic DNA fragments mere sequenced; all 10 ORFs found mere without introns and they have homologues in S, cerevisiae. Gene order comparison revealed that the organization is partially conserved in both species. The genome of P. sorbitophila CBS 7064 consists of seven chromosomes with an approximate size of 1.0-2.9 Mb, 13.9 Mb in total, Three of the chromosomes were labelled with specific probes. The sequencing of a 5.2 kb genomic DNA fragment revealed three ORFs, but no conservation of their organization was found, although all of them have their respective homologues in S, cerevisiae. According to our results, the presence of two overlapping ORFs in S, cerevisiae (YJL107c-YJL108c) could be interpreted as the result of a frameshift mutation. The Accession Nos of the sequenced DIVA fragments are: Y18561, AJ25115, Y18560 and Y18559. Copyright (C) 2000 John Wiley & Sons, Ltd.