Insights into variability of actinorhodopsin genes of the LG1 cluster in two different freshwater habitats

0394407 - BC 2014 RIV US eng J - Journal Article
Jezberová, Jitka - Jezbera, Jan - Hahn, M.W.
Insights into variability of actinorhodopsin genes of the LG1 cluster in two different freshwater habitats.
PLoS ONE. Roč. 8, č. 7 (2013), e68542. ISSN 1932-6203. E-ISSN 1932-6203
R&D Projects: GA ČR(CZ) GEEEF/10/E011
Institutional support: RVO:60077344
Keywords : actinobacteria * bacteria * bacterioplankton * diversity * sequences * lakes
Subject RIV: EE - Microbiology, Virology
Impact factor: 3.534, year: 2013

Actinorhodopsins (ActRs) are recently discovered proteorhodopsins present in Actinobacteria, enabling them to adapt to a wider spectrum of environmental conditions. Frequently, a large fraction of freshwater bacterioplankton belongs to the acI lineage of Actinobacteria and codes the LG1 type of ActRs. In this paper we studied the genotype variability of the LG1 ActRs. We have constructed two clone libraries originating from two environmentally different habitats located in Central Europe; the large alkaline lake Mondsee (Austria) and the small humic reservoir Jiricka (the Czech Republic). The 75 yielded clones were phylogenetically analyzed together with all ActR sequences currently available in public databases. Altogether 156 sequences were analyzed and 13 clusters of ActRs were distinguished. Newly obtained clones are distributed over all three LG1 subgroups - LG1-A, B and C. Eighty percent of the sequences belonged to the acI lineage (LG1-A ActR gene bearers) further divided into LG1-A1 and LG1-A2 subgroups. Interestingly, the two habitats markedly differed in genotype composition with no identical sequence found in both samples of clones. Moreover, Jiricka reservoir contained three so far not reported clusters, one of them LG1-C related, presenting thus completely new, so far undescribed, genotypes of Actinobacteria in freshwaters.
Permanent Link: http://hdl.handle.net/11104/0222832