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CO(2) acts as a signalling molecule in populations of the fungal pathogen Candida albicans.

ABSTRACT: When colonising host-niches or non-animated medical devices, individual cells of the fungal pathogen Candida albicans expand into significant biomasses. Here we show that within such biomasses, fungal metabolically generated CO(2) acts as a communication molecule promoting the switch from yeast to filamentous growth essential for C. albicans pathology. We find that CO(2)-mediated intra-colony signalling involves the adenylyl cyclase protein (Cyr1p), a multi-sensor recently found to coordinate fungal responses to serum and bacterial peptidoglycan. We further identify Lys 1373 as essential for CO(2)/bicarbonate regulation of Cyr1p. Disruption of the CO(2)/bicarbonate receptor-site interferes selectively with C. albicans filamentation within fungal biomasses. Comparisons between the Drosophila melanogaster infection model and the mouse model of disseminated candidiasis, suggest that metabolic CO(2) sensing may be important for initial colonisation and epithelial invasion. Our results reveal the existence of a gaseous Candida signalling pathway and its molecular mechanism and provide insights into an evolutionary conserved CO(2)-signalling system.

SUBMITTER: Hall RA

PROVIDER: S-EPMC2987819 | biostudies-literature | 2010 Nov

REPOSITORIES: biostudies-literature

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CO(2) acts as a signalling molecule in populations of the fungal pathogen Candida albicans.

Hall Rebecca A RA De Sordi Luisa L Maccallum Donna M DM Topal Hüsnü H Eaton Rebecca R Bloor James W JW Robinson Gary K GK Levin Lonny R LR Buck Jochen J Wang Yue Y Gow Neil A R NA Steegborn Clemens C Mühlschlegel Fritz A FA

PLoS pathogens 20101118 11

When colonising host-niches or non-animated medical devices, individual cells of the fungal pathogen Candida albicans expand into significant biomasses. Here we show that within such biomasses, fungal metabolically generated CO(2) acts as a communication molecule promoting the switch from yeast to filamentous growth essential for C. albicans pathology. We find that CO(2)-mediated intra-colony signalling involves the adenylyl cyclase protein (Cyr1p), a multi-sensor recently found to coordinate fu ...[more]

PMID: 21124988

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CO(2) acts as a signalling molecule in populations of the fungal pathogen Candida albicans.

Publications

CO(2) acts as a signalling molecule in populations of the fungal pathogen Candida albicans.

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