Comparative single-cell genomics reveals potential ecological niches for the freshwater acl Actinobacteria lineage

Ghylin, Trevor W.; Garcia, Sarahi L.; Moya, Francisco; Oyserman, Ben O.; Schwientek, Patrick; Forest, Katrina T.; Mutschler, James; Dwulit-Smith, Jeffrey; Chan, Leong-Keat; Martinez-Garcia, Manuel; Sczyrba, Alexander; Stepanauskas, Ramunas; Grossart, Hans-Peter; Woyke, Tanja; Warnecke, Falk; et. al.

Abstract

Members of the acI lineage of Actinobacteria are the most abundant microorganisms in most freshwater lakes; however, our understanding of the keys to their success and their role in carbon and nutrient cycling in freshwater systems has been hampered by the lack of pure cultures and genomes. We obtained draft genome assemblies from 11 single cells representing three acI tribes (acI-A1, acI-A7, acI-B1) from four temperate lakes in the United States and Europe. Comparative analysis of acI SAGs and other available freshwater bacterial genomes showed that acI has more gene content directed toward carbohydrate acquisition as compared to Polynucleobacter and LD12 Alphaproteobacteria, which seem to specialize more on carboxylic acids. The acI genomes contain actinorhodopsin as well as some genes involved in anaplerotic carbon fixation indicating the capacity to supplement their known heterotrophic lifestyle. Genome-level differences between the acI-A and acI-B clades suggest specialization at the clade level for carbon substrate acquisition. Overall, the acI genomes appear to be highly streamlined versions of Actinobacteria that include some genes allowing it to take advantage of sunlight and N-rich organic compounds such as polyamines, di-and oligopeptides, branched-chain amino acids and cyanophycin. This work significantly expands the known metabolic potential of the cosmopolitan freshwater acI lineage and its ecological and genetic traits.

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Título según WOS: ID WOS:000345498200015 Not found in local WOS DB
Título de la Revista: ISME JOURNAL
Volumen: 8
Número: 12
Editorial: OXFORD UNIV PRESS
Fecha de publicación: 2014
Página de inicio: 2503
Página final: 2516
DOI:

10.1038/ismej.2014.135

Notas: ISI