Comparative Analysis of Glycoside Hydrolases Activities from Phylogenetically Diverse Marine Bacteria of the Genus Arenibacter

Irina Bakunina,Valery Mikhailov,Valery Rasskasov,Tatyana Zvyagintseva,Olga Nedashkovskaya,Larissa Balabanova

doi:10.3390/md11061977

Abstract

A total of 16 marine strains belonging to the genus Arenibacter, recovered from diverse microbial communities associated with various marine habitats and collected from different locations, were evaluated in degradation of natural polysaccharides and chromogenic glycosides. Most strains were affiliated with five recognized species, and some presented three new species within the genus Arenibacter. No strains contained enzymes depolymerizing polysaccharides, but synthesized a wide spectrum of glycosidases. Highly active β-N-acetylglucosaminidases and α-N-acetylgalactosaminidases were the main glycosidases for all Arenibacter. The genes, encoding two new members of glycoside hydrolyses (GH) families, 20 and 109, were isolated and characterized from the genomes of Arenibacter latericius. Molecular genetic analysis using glycosidase-specific primers shows the absence of GH27 and GH36 genes. A sequence comparison with functionally-characterized GH20 and GH109 enzymes shows that both sequences are closest to the enzymes of chitinolytic bacteria Vibrio furnissii and Cellulomonas fimi of marine and terrestrial origin, as well as human pathogen Elisabethkingia meningoseptica and simbionts Akkermansia muciniphila, gut and non-gut Bacteroides, respectively. These results revealed that the genus Arenibacter is a highly taxonomic diverse group of microorganisms, which can participate in degradation of natural polymers in marine environments depending on their niche and habitat adaptations. They are new prospective candidates for biotechnological applications due to their production of unique glycosidases.

Highlights

Bacteroidetes represents one of the main evolutionary branches of the domain Bacteria and one of the dominant components of the marine microbiota
Some types of strains of the genus Arenibacter were recovered from various marine environments, including bottom-sediment samples, the brown alga Chorda filum, the green alga Ulva fenestrata and the edible holothurian Apostichopus japonicus, collected from Sea of Japan, Sea of Okhotsk and South China Sea in the Pacific Ocean
We have previously shown that the some strains of the genus Arenibacter cannot degrade several high molecular weight natural biopolymers but they synthesized a wide range of glycosidases: α- and β-galactosidases, β-glucosidases, α-N-acetylgalactosaminidases, β-N-acetylglucosaminidases, α-fucosidases, α-mannosidases and β-xylosidases [24,25]

Summary

Introduction

Bacteroidetes represents one of the main evolutionary branches of the domain Bacteria and one of the dominant components of the marine microbiota. The genus Arenibacter, a member of marine clade of the family Flavobacteriaceae of the phylum. Bacteroidetes, was proposed by Ivanova et al [1] to accommodate Gram-negative, heterotrophic, aerobic and pigmented bacteria of marine origin. Members of the genus are Gram-negative, aerobic, heterotrophic and dark-orange-pigmented marine bacteria. Some types of strains of the genus Arenibacter were recovered from various marine environments, including bottom-sediment samples, the brown alga Chorda filum, the green alga Ulva fenestrata and the edible holothurian Apostichopus japonicus, collected from Sea of Japan, Sea of Okhotsk and South China Sea in the Pacific Ocean

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