title: Falsirhodobacter sp. alg1 Harbors Single Homologs of Endo and Exo-Type Alginate Lyases Efficient for Alginate Depolymerization.
abstract: Alginate-degrading bacteria play an important role in alginate degradation by harboring highly efficient and unique alginolytic genes. Although the general mechanism for alginate degradation by these bacteria is fairly understood, much is still required to fully exploit them. Here, we report the isolation of a novel strain, Falsirhodobacter sp. alg1, the first report for an alginate-degrading bacterium from the family Rhodobacteraceae. Genome sequencing reveals that strain alg1 harbors a primary alginate degradation pathway with only single homologs of an endo- and exo-type alginate lyase, AlyFRA and AlyFRB, which is uncommon among such bacteria. Subsequent functional analysis showed that both enzymes were extremely efficient to depolymerize alginate suggesting evolutionary interests in the acquirement of these enzymes. The exo-type alginate lyase, AlyFRB in particular could depolymerize alginate without producing intermediate products making it a highly efficient enzyme for the production of 4-deoxy-L-erythro-5-hexoseulose uronic acid (DEH). Based on our findings, we believe that the discovery of Falsirhodobacter sp. alg1 and its alginolytic genes hints at the potentiality of a more diverse and unique population of alginate-degrading bacteria.
authors.affiliation: Faculty of Science and Engineering, Waseda University, Tokyo, Japan.
authors.forename: Tetsushi
authors.identifier: 0000-0001-7096-4161
authors.initials: T
authors.lastname: Mori
authors.affiliation: Faculty of Science and Engineering, Waseda University, Tokyo, Japan.
authors.forename: Mami
authors.initials: M
authors.lastname: Takahashi
authors.affiliation: Department of Life Sciences, Graduate School of Bioresources, Mie University, Mie, Japan.
authors.forename: Reiji
authors.initials: R
authors.lastname: Tanaka
authors.affiliation: Department of Life Sciences, Graduate School of Bioresources, Mie University, Mie, Japan.
authors.forename: Hideo
authors.initials: H
authors.lastname: Miyake
authors.affiliation: Department of Life Sciences, Graduate School of Bioresources, Mie University, Mie, Japan.
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Shibata
authors.affiliation: Research Center for Aquatic Genomics, National Research Institute of Fisheries Science, Kanagawa, Japan.
authors.forename: Seinen
authors.initials: S
authors.lastname: Chow
authors.affiliation: Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan.
authors.forename: Kouichi
authors.initials: K
authors.lastname: Kuroda
authors.affiliation: Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan.
authors.forename: Mitsuyoshi
authors.initials: M
authors.lastname: Ueda
authors.affiliation: Faculty of Science and Engineering, Waseda University, Tokyo, Japan.
authors.forename: Haruko
authors.initials: H
authors.lastname: Takeyama
mesh_terms: D000464:Alginates / Q000378:metabolism*; D001483:Base Sequence; D002855:Chromatography, Thin Layer; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D020723:Glucuronic Acid / Q000378:metabolism; D006603:Hexuronic Acids / Q000378:metabolism; D009876:Operon / Q000235:genetics; D010802:Phylogeny; D058105:Polymerization; D011133:Polysaccharide-Lyases / Q000235:genetics / Q000378:metabolism*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D015203:Reproducibility of Results; D016992:Rhodobacter / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification; D017386:Sequence Homology, Amino Acid
chemical_list: D000464:Alginates; D006603:Hexuronic Acids; D012336:RNA, Ribosomal, 16S; D020723:Glucuronic Acid; D011133:Polysaccharide-Lyases; C016158:poly(beta-D-mannuronate) lyase