title: Bacterial community dynamics during polysaccharide degradation at contrasting sites in the Southern and Atlantic Oceans.
abstract: The bacterial degradation of polysaccharides is central to marine carbon cycling, but little is known about the bacterial taxa that degrade specific marine polysaccharides. Here, bacterial growth and community dynamics were studied during the degradation of the polysaccharides chitin, alginate and agarose in microcosm experiments at four contrasting locations in the Southern and Atlantic Oceans. At the Southern polar front, chitin-supplemented microcosms were characterized by higher fractions of actively growing cells and a community shift from Alphaproteobacteria to Gammaproteobacteria and Bacteroidetes. At the Antarctic ice shelf, chitin degradation was associated with growth of Bacteroidetes, with 24% higher cell numbers compared with the control. At the Patagonian continental shelf, alginate and agarose degradation covaried with growth of different Alteromonadaceae populations, each with specific temporal growth patterns. At the Mauritanian upwelling, only the alginate hydrolysis product guluronate was consumed, coincident with increasing abundances of Alteromonadaceae and possibly cross-feeding SAR11. 16S rRNA gene amplicon libraries indicated that growth of the Bacteroidetes-affiliated genus Reichenbachiella was stimulated by chitin at all cold and temperate water stations, suggesting comparable ecological roles over wide geographical scales. Overall, the predominance of location-specific patterns showed that bacterial communities from contrasting oceanic biomes have members with different potentials to hydrolyse polysaccharides.
authors.affiliation: Institute for Chemistry and Biology of the Marine Environment, University of Oldenburg, Oldenburg, 26129, Germany.
authors.forename: Matthias
authors.identifier: http://orcid.org/0000-0002-9786-3026
authors.initials: M
authors.lastname: Wietz
authors.affiliation: Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, University of Göttingen, Göttingen, 37077, Germany.
authors.forename: Bernd
authors.initials: B
authors.lastname: Wemheuer
authors.affiliation: Institute for Chemistry and Biology of the Marine Environment, University of Oldenburg, Oldenburg, 26129, Germany.
authors.forename: Heike
authors.initials: H
authors.lastname: Simon
authors.affiliation: Institute for Chemistry and Biology of the Marine Environment, University of Oldenburg, Oldenburg, 26129, Germany.
authors.forename: Helge-Ansgar
authors.initials: HA
authors.lastname: Giebel
authors.affiliation: ICBM-MPI Bridging Group for Marine Geochemistry, Institute for Chemistry and Biology of the Marine Environment, University of Oldenburg, Oldenburg, 26129, Germany.
authors.forename: Maren A
authors.initials: MA
authors.lastname: Seibt
authors.affiliation: Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, University of Göttingen, Göttingen, 37077, Germany.
authors.forename: Rolf
authors.initials: R
authors.lastname: Daniel
authors.affiliation: Institute for Chemistry and Biology of the Marine Environment, University of Oldenburg, Oldenburg, 26129, Germany.
authors.forename: Thorsten
authors.initials: T
authors.lastname: Brinkhoff
authors.affiliation: Institute for Chemistry and Biology of the Marine Environment, University of Oldenburg, Oldenburg, 26129, Germany.
authors.forename: Meinhard
authors.initials: M
authors.lastname: Simon
mesh_terms: D000464:Alginates / Q000378:metabolism; D020561:Alphaproteobacteria / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D034241:Alteromonadaceae / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D000864:Antarctic Regions; D001267:Atlantic Ocean; D041963:Bacteroidetes / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D002686:Chitin / Q000378:metabolism; D003080:Cold Temperature; D017753:Ecosystem; D005843:Geography; D020723:Glucuronic Acid / Q000378:metabolism; D006603:Hexuronic Acids / Q000378:metabolism; D059013:Microbial Consortia / Q000502:physiology*; D009792:Oceans and Seas; D011134:Polysaccharides / Q000378:metabolism*; D012336:RNA, Ribosomal, 16S / Q000235:genetics
chemical_list: D000464:Alginates; D006603:Hexuronic Acids; D011134:Polysaccharides; D012336:RNA, Ribosomal, 16S; D002686:Chitin; C007896:guluronic acid; D020723:Glucuronic Acid