title: Different utilization of alginate and other algal polysaccharides by marine Alteromonas macleodii ecotypes.
abstract: The marine bacterium Alteromonas macleodii is a copiotrophic r-strategist, but little is known about its potential to degrade polysaccharides. Here, we studied the degradation of alginate and other algal polysaccharides by A. macleodii strain 83-1 in comparison to other A. macleodii strains. Cell densities of strain 83-1 with alginate as sole carbon source were comparable to those with glucose, but the exponential phase was delayed. The genome of 83-1 was found to harbour an alginolytic system comprising five alginate lyases, whose expression was induced by alginate. The alginolytic system contains additional CAZymes, including two TonB-dependent receptors, and is part of a 24 kb genomic island unique to the A. macleodii 'surface clade' ecotype. In contrast, strains of the 'deep clade' ecotype contain only a single alginate lyase in a separate 7 kb island. This difference was reflected in an eightfold greater efficiency of surface clade strains to grow on alginate. Strain 83-1 furthermore hydrolysed laminarin, pullulan and xylan, and corresponding polysaccharide utilization loci were detected in the genome. Alteromonas macleodii alginate lyases were predominantly detected in Atlantic Ocean metagenomes. The demonstrated hydrolytic capacities are likely of ecological relevance and represent another level of adaptation among A. macleodii ecotypes.
authors.affiliation: Institute for Chemistry and Biology of the Marine Environment, University of Oldenburg, Oldenburg, 26129, Germany.
authors.forename: Anna M
authors.initials: AM
authors.lastname: Neumann
authors.affiliation: Department of Marine Sciences, University of North Carolina, 3117 Venable Hall, Chapel Hill, NC, USA.
authors.forename: John P
authors.initials: JP
authors.lastname: Balmonte
authors.affiliation: Institute for Chemistry and Biology of the Marine Environment, University of Oldenburg, Oldenburg, 26129, Germany.
authors.forename: Martine
authors.initials: M
authors.lastname: Berger
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: Department of Marine Sciences, University of North Carolina, 3117 Venable Hall, Chapel Hill, NC, USA.
authors.forename: Carol
authors.initials: C
authors.lastname: Arnosti
authors.affiliation: Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, University of Göttingen, Göttingen, 37077, Germany.
authors.forename: Sonja
authors.initials: S
authors.lastname: Voget
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
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: Matthias
authors.identifier: http://orcid.org/0000-0002-9786-3026
authors.initials: M
authors.lastname: Wietz
mesh_terms: D000464:Alginates / Q000378:metabolism*; D020591:Alteromonas / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D059001:Aquatic Organisms / Q000235:genetics / Q000378:metabolism*; D001267:Atlantic Ocean; D001426:Bacterial Proteins / Q000235:genetics; D060146:Ecotype; D004734:Energy Metabolism / Q000502:physiology*; D016680:Genome, Bacterial / Q000235:genetics; D044404:Genomic Islands / Q000235:genetics; D005936:Glucans / Q000378:metabolism; D020723:Glucuronic Acid / Q000378:metabolism; D006603:Hexuronic Acids / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics; D054892:Metagenome / Q000235:genetics; D011133:Polysaccharide-Lyases / Q000235:genetics* / Q000378:metabolism; D012623:Seawater / Q000382:microbiology; D014990:Xylans / Q000378:metabolism
chemical_list: D000464:Alginates; D001426:Bacterial Proteins; D005936:Glucans; D006603:Hexuronic Acids; D008565:Membrane Proteins; D014990:Xylans; C057616:tonB protein, Bacteria; D020723:Glucuronic Acid; C009109:pullulan; C008247:laminaran; D011133:Polysaccharide-Lyases; C016158:poly(beta-D-mannuronate) lyase