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bioRxiv · 10.1101/2023.03.13.532333

Zobellia alginoliquefaciens sp. nov. , a new flavobacteria isolated from the epibiota of the brown alga Ericaria zosteroides (C.Agardh) Molinari & Guiry 2020

Barbeyron, T.·Le Duff, N.·Duchaud, E.·THOMAS, F.
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Abstract

Strain LLG6346-3.1T, isolated from the thallus of the brown alga Ericaria zosteroides collected in Mediterranean Sea near Bastia in Corsica, France, was characterized using a polyphasic method. Cells were Gram-stain-negative, strictly aerobic, non-flagellated, motile by gliding, rod-shaped and grew optimally at 30-33 {degrees}C, at pH 8-8.5 and with 4-5 % NaCl. Strain LLG6346-3.1T used the seaweed polysaccharide alginic acid as sole carbon source which was vigorously liquefied. Phylogenetic analyses showed that the bacterium is affiliated to the genus Zobellia (family Flavobacteriaceae, class Flavobacteriia). Strain LLG6346-3.1T exhibited 16S rRNA gene sequence similarity values of 98.5 and 98.3 % to the type strains of Zobellia russellii and Zobellia roscoffensis respectively, and of 97.4-98.2 % to other species of the genus Zobellia. The DNA G+C content of strain LLG6346-3.1T was determined to be 38.28 mol%. Digital DNA-DNA hybridization predictions by the ANI and GGDC methods between strain LLG6346-3.1T and other members of the genus Zobellia showed values of 76-88 %, and below 37 %, respectively. The phenotypic, phylogenetic and genomic analyses show that strain LLG6346-3.1T is distinct from species of the genus Zobellia with validly published names and that it represents a novel species of the genus Zobellia, for which the name Zobellia alginoliquefaciens sp. nov. is proposed. The type strain is LLG6346-3.1T (RCC 7657T = LLG 32918T).

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Barbeyron, T., Le Duff, N., Duchaud, E., THOMAS, F.. 2023-03-13. Zobellia alginoliquefaciens sp. nov. , a new flavobacteria isolated from the epibiota of the brown alga Ericaria zosteroides (C.Agardh) Molinari & Guiry 2020. https://doi.org/10.1101/2023.03.13.532333

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