HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Cong, Y.-S. Articles by Fukuhara, H. Search for Related Content PubMed PubMed Citation Articles by Cong, Y.-S. Articles by Fukuhara, H. Agricola Articles by Cong, Y.-S. Articles by Fukuhara, H.

Linear DNA plasmids from Pichia etchellsii, Debaryomyces hansenii and Wingea robertsiae

Institut Curie, Section de Biologie, Batiment 110, Centre Universitaire Paris XI, Orsay 91405 France
Centraalbureau voor Schimmelcultures, Yeast Division, 2628 BC Delft, The Netherlands
Genetics Institute, Fudan University, Shanghai 200433, China

^*Author for correspondence: Hiroshi Fukuhara. Tel: +33 1 69 86 30 63. Fax: +33 1 69 86 94 29.

ABSTRACT

Linear DNA plasmids were found in the following yeasts: four strains of Kluyveromyces lactis, one of Debaryomyces hansenii, one of Winges robertsiae and four of Pichia etchellsii. In each case, the plasmids were present as a pair of DNA molecules of different sizes. The plasmids of K. lactis strains were associated with a killer activity and their structure was similar to the known killer plasmids pGKL1 and 2. The plasmids from the other three species were different from pGKL plasmids and showed no killer activity against the yeast species tested so far. In all cases, the linear molecules possessed terminal (probably inverted) repeats and their 5' ends had a protected structure insensitive to exonuclease, while the 3' ends were accessible to exonuclease III. All these strains could be efficiently cured of the plasmids by ultraviolet irradiation. The plasmids from D. hansenii (pDH1 A and B) and from W. robertsiae (pWR1A and B) shared related sequences with some of the K. lactis killer plasmid genes (encoding the supposed DNA polymerases, RNA polymerase and the chitinase), suggesting related genome organization of these plasmids. The pair of plasmids from P. etchellsii (pPE1 A and B) appear to be a distantly related member of the group. This pair showed no sequence homology with other plasmids, except weak homology with the putative RNA polymerase gene of pGKL2. None of the plasmids contained the sequences homologous to ORF3 and ORF4 of pGKL1 encoding the toxin resistance determinant and the toxin subunit, respectively.