Candida Infection Biology – fungal armoury, battlefields ... - FINSysB

Poster number: 24
Characterization of the Candida albicans PKH1 and YPK1
genes for their roles in biofilm formation and cell wall
integrity
Vitor Cabral 1,2 , Arnaud Firon 1,2 , Tobias Schwarzmüller 3 , Karl Kuchler 3 ,
Christophe d’Enfert 1,2 and Sophie Bachellier-Bassi 1,2
1 Institut Pasteur, Unité Biologie et Pathogénicité Fongiques, Département Génomes et
Génétique, F-75015 Paris, France; 2 INRA, USC2019, F-75015 Paris, France; 3 Medical
University Vienna, Max F. Perutz Laboratories, Christian Doppler Laboratory for Infection
Biology, Department of Medical Biochemistry, A-1030 Vienna, Austria
In Saccharomyces cerevisiae, the Pkh1/Pkh2 and Ypk1/Ypk2 protein kinases are
part of a signaling cascade important for maintenance of cell wall integrity. Our
analysis of a large collection of Candida glabrata knock-out mutants for their ability
to form biofilms has revealed that the C. glabrata Pkh2 protein kinase
(CAGL0I07513g) is necessary for growth on solid surfaces and efficient biofilm
formation while Pkh1/CAGL0G04609g is not (Schwarzmüller et al., in preparation).
Candida albicans has only one gene for the Pkh protein kinase and one gene for
the Ypk protein kinase that we have named PKH1 and YPK1, respectively. In order
to test whether the Pkh1 and Ypk1 protein kinases also play a role in biofilm
formation in C. albicans, heterozygous and homozygous knockout mutants for the
YPK1 and PKH1 genes have been constructed. Preliminary data show that the
ypk1∆/ypk1∆ knock-out mutant has altered sensitivity to the cell wall perturbing
agents Congo Red and Calcofluor White suggesting that Ypk1 might perform a
function similar to that of Ypk1 and Ypk2 in S. cerevisiae. Additional studies of these
mutants and complemented strains are ongoing and will be presented.
We are grateful to the European Commission for funding the FINSysB Marie Curie Initial Training Network
(PITN-GA-2008-214004).
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