An integrated study of photochemical function and expression of a key photochemical gene (psbA) in photosynthetic communities of Lake Bonney (McMurdo Dry Valleys, Antarctica)

0440894 - MBÚ 2015 RIV GB eng J - Journal Article
Kong, W. - Wei, L. - Romancová, Ingrid - Prášil, Ondřej - Morgan-Kiss, R. M.
An integrated study of photochemical function and expression of a key photochemical gene (psbA) in photosynthetic communities of Lake Bonney (McMurdo Dry Valleys, Antarctica).
FEMS Microbiology Ecology. Roč. 89, č. 6 (2014), s. 293-302. ISSN 0168-6496. E-ISSN 1574-6941
R&D Projects: GA MŠMT ED2.1.00/03.0110
Grant - others:NSF Office of Polar Programs(US) OPP-0631659, OPP-1056396
Institutional support: RVO:61388971
Keywords : photochemistry * lake Bonnney * communities
Subject RIV: EE - Microbiology, Virology
Impact factor: 3.568, year: 2014

Lake Bonney is one of several permanently ice-covered lakes in the McMurdo Dry Valleys, Antarctica, which maintain the only year-round biological activity on the Antarctic continent. Vertically stratified populations of autotrophic microorganisms occupying the water columns are adapted to numerous extreme conditions, including very low light, hypersalinity, ultra-oligotrophy and low temperatures. In this study, we integrated molecular biology, microscopy, flow cytometry, and functional photochemical analyses of the photosynthetic communities residing in the east and west basins of dry valley Lake Bonney. Diversity and abundance of the psbA gene encoding a major protein of the photosystem II reaction center were monitored during the seasonal transition between Antarctic summer (24-h daylight) to winter (24-h darkness). Vertical trends through the photic zone in psbA abundance (DNA and mRNA) closely matched that of primary production in both lobes. Seasonal trends in psbA transcripts differed between the two lobes, with psbA expression in the west basin exhibiting a transient rise in early Fall. Last, using spectroscopic and flow cytometric analyses, we provide the first evidence that the Lake Bonney photosynthetic community is dominated by picophytoplankton that possess photosynthetic apparatus adapted to extreme shade.
Permanent Link: http://hdl.handle.net/11104/0243986