title: The genome of the alga-associated marine flavobacterium Formosa agariphila KMM 3901T reveals a broad potential for degradation of algal polysaccharides.
abstract: In recent years, representatives of the Bacteroidetes have been increasingly recognized as specialists for the degradation of macromolecules. Formosa constitutes a Bacteroidetes genus within the class Flavobacteria, and the members of this genus have been found in marine habitats with high levels of organic matter, such as in association with algae, invertebrates, and fecal pellets. Here we report on the generation and analysis of the genome of the type strain of Formosa agariphila (KMM 3901(T)), an isolate from the green alga Acrosiphonia sonderi. F. agariphila is a facultative anaerobe with the capacity for mixed acid fermentation and denitrification. Its genome harbors 129 proteases and 88 glycoside hydrolases, indicating a pronounced specialization for the degradation of proteins, polysaccharides, and glycoproteins. Sixty-five of the glycoside hydrolases are organized in at least 13 distinct polysaccharide utilization loci, where they are clustered with TonB-dependent receptors, SusD-like proteins, sensors/transcription factors, transporters, and often sulfatases. These loci play a pivotal role in bacteroidetal polysaccharide biodegradation and in the case of F. agariphila revealed the capacity to degrade a wide range of algal polysaccharides from green, red, and brown algae and thus a strong specialization of toward an alga-associated lifestyle. This was corroborated by growth experiments, which confirmed usage particularly of those monosaccharides that constitute the building blocks of abundant algal polysaccharides, as well as distinct algal polysaccharides, such as laminarins, xylans, and κ-carrageenans.
authors.affiliation: Max Planck Institute for Marine Microbiology, Bremen, Germany.
authors.forename: Alexander J
authors.initials: AJ
authors.lastname: Mann
authors.forename: Richard L
authors.initials: RL
authors.lastname: Hahnke
authors.forename: Sixing
authors.initials: S
authors.lastname: Huang
authors.forename: Johannes
authors.initials: J
authors.lastname: Werner
authors.forename: Peng
authors.initials: P
authors.lastname: Xing
authors.forename: Tristan
authors.initials: T
authors.lastname: Barbeyron
authors.forename: Bruno
authors.initials: B
authors.lastname: Huettel
authors.forename: Kurt
authors.initials: K
authors.lastname: Stüber
authors.forename: Richard
authors.initials: R
authors.lastname: Reinhardt
authors.forename: Jens
authors.initials: J
authors.lastname: Harder
authors.forename: Frank Oliver
authors.initials: FO
authors.lastname: Glöckner
authors.forename: Rudolf I
authors.initials: RI
authors.lastname: Amann
authors.forename: Hanno
authors.initials: H
authors.lastname: Teeling
mesh_terms: D001483:Base Sequence; D000460:Chlorophyta / Q000382:microbiology*; D041965:Flavobacteriaceae / Q000235:genetics* / Q000378:metabolism; D016680:Genome, Bacterial / Q000235:genetics*; D006026:Glycoside Hydrolases / Q000235:genetics / Q000378:metabolism; D058977:Molecular Sequence Annotation; D008969:Molecular Sequence Data; D011134:Polysaccharides / Q000378:metabolism*; D017422:Sequence Analysis, DNA; D013045:Species Specificity
chemical_list: D011134:Polysaccharides; D006026:Glycoside Hydrolases