FN Archimer Export Format
PT J
TI Evolutionary Evidence of Algal Polysaccharide Degradation Acquisition by Pseudoalteromonas carrageenovora 9(T) to Adapt to Macroalgal Niches
BT 
AF GOBET, Angelique
   BARBEYRON, Tristan
   MATARD-MANN, Maria
   MAGDELENAT, Ghislaine
   VALLENET, David
   DUCHAUD, Eric
   MICHEL, Gurvan
AS 1:1;2:1;3:1,2;4:3;5:3;6:4;7:1;
FF 1:;2:;3:;4:;5:;6:;7:;
C1 Sorbonne Univ, CNRS, Integrat Biol Marine Models LBI2M, SBR, Roscoff, France.
   Amadeite SAS, Poke Biotechnol Haut Bois, Brehan, France.
   Univ Paris Sacisy, Univ Evry, Genom Metab, Genoscope,Inst Francois Jacob,CEA,CNRS, Evry, France.
   Univ Paris Saclay, VIM, INRA, Jouy En Josas, France.
C2 UNIV PARIS 06, FRANCE
   AMADEITE SAS, FRANCE
   UNIV PARIS SACISY, FRANCE
   UNIV PARIS SACLAY, FRANCE
IF 4.259
TC 38
UR https://archimer.ifremer.fr/doc/00489/60070/63377.pdf
   https://archimer.ifremer.fr/doc/00489/60070/63378.xlsx
   https://archimer.ifremer.fr/doc/00489/60070/63379.xlsx
   https://archimer.ifremer.fr/doc/00489/60070/63380.xlsx
   https://archimer.ifremer.fr/doc/00489/60070/63381.xlsx
   https://archimer.ifremer.fr/doc/00489/60070/63382.xlsx
   https://archimer.ifremer.fr/doc/00489/60070/63383.xlsx
   https://archimer.ifremer.fr/doc/00489/60070/63384.xlsx
   https://archimer.ifremer.fr/doc/00489/60070/63385.xlsx
   https://archimer.ifremer.fr/doc/00489/60070/63386.pdf
   https://archimer.ifremer.fr/doc/00489/60070/63387.pdf
LA English
DT Article
DE ;carrageenan;CAZymes;alginate;Gammaproteobacteria;Pseudoalteromonas;marine bacteria;algal holobiont;biofilm
AB About half of seaweed biomass is composed of polysaccharides. Most of these complex polymers have a marked polyanionic character. For instance, the red algal cell wall is mainly composed of sulfated galactans, agars and carrageenans, while brown algae contain alginate and fucose-containing sulfated polysaccharides (FCSP) as cell wall polysaccharides. Some marine heterotrophic bacteria have developed abilities to grow on such macroalgal polysaccharides. This is the case of Pseudoalteromonas carrageenovora 9(T) (ATCC 43555(T)), a marine gammaproteobacterium isolated in 1955 and which was an early model organism for studying carrageenan catabolism. We present here the genomic analysis of P. carrageenovora. Its genome is composed of two chromosomes and of a large plasmid encompassing 109 protein-coding genes. P. carrageenovora possesses a diverse repertoire of carbohydrate-active enzymes (CAZymes), notably specific for the degradation of macroalgal polysaccharides (laminarin, alginate, FCSP, carrageenans). We confirm these predicted capacities by screening the growth of P. carrageenovora with a large collection of carbohydrates. Most of these CAZyme genes constitute clusters located either in the large chromosome or in the small one. Unexpectedly, all the carrageenan catabolism-related genes are found in the plasmid, suggesting that P. carrageenovora acquired its hallmark capacity for carrageenan degradation by horizontal gene transfer (HGT). Whereas P. carrageenovora is able to use lambda-carrageenan as a sole carbon source, genomic and physiological analyses demonstrate that its catabolic pathway for kappa- and iota-carrageenan is incomplete. This is due to the absence of the recently discovered 3,6-anhydro-D-galactosidase genes (GH127 and GH129 families). A genomic comparison with 52 Pseudoalteromonas strains confirms that carrageenan catabolism has been recently acquired only in a few species. Even though the loci for cellulose biosynthesis and alginate utilization are located on the chromosomes, they were also horizontally acquired. However, these HGTs occurred earlier in the evolution of the Pseudoalteromonas genus, the cellulose- and alginate-related loci being essentially present in one large, late-diverging clade (LDC). Altogether, the capacities to degrade cell wall polysaccharides from macroalgae are not ancestral in the Pseudoalteromonas genus. Such catabolism in P. carrageenovora resulted from a succession of HGTs, likely allowing an adaptation to the life on the macroalgal surface. 
PY 2018
PD NOV
SO Frontiers In Microbiology
SN 1664-302X
PU Frontiers Media Sa
VL 9
IS 2740
UT 000450891500001
DI 10.3389/fmicb.2018.02740
ID 60070
ER

EF