Paenimyroides aestuarii gen. nov. sp. nov., a novel bacterium isolated from sediment in the Pearl River Estuary and reclassification of five Flavobacterium and four Myroides species

Kun Zhang; Linqing Cui; Qi Zeng; Songbiao Shi; Lijuan Long; Xinpeng Tian

doi:10.1099/ijsem.0.006091

Paenimyroides aestuarii gen. nov. sp. nov., a novel bacterium isolated from sediment in the Pearl River Estuary and reclassification of five Flavobacterium and four Myroides species

Int J Syst Evol Microbiol. 2023 Oct;73(10). doi: 10.1099/ijsem.0.006091.

Authors

Kun Zhang^{1

2

3}, Linqing Cui^{1

2

3}, Qi Zeng^{1

3}, Songbiao Shi^{1

2

3}, Lijuan Long^{1

2}, Xinpeng Tian^{1

2}

Affiliations

¹ CAS Key Laboratory of Tropical Marine Bio-resources and Ecology; Guangdong Key Laboratory of Marine Materia Medica; RNAM Center for Marine Microbiology; South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, Guangdong 510301, PR China.
² Sanya Institute of Ocean Eco-Environmental Engineering, Yazhou Scientific Bay, Sanya 572000, PR China.
³ University of Chinese Academy of Sciences, Beijing 100049, PR China.

PMID: 37882776
DOI: 10.1099/ijsem.0.006091

Abstract

An aerobic, Gram-negative, non-motile, yellow-to-orange pigmented and round bacterium, designated strain SCSIO 72103^T, was isolated from sediment collected in the Pearl River Estuary, Guangdong Province, PR China and subjected to a polyphasic taxonomic study. Growth occurred at 20-37 °C (optimum, 28 °C), pH 6-8 (optimum, pH 7) and with 1-5.5% NaCl (optimum, 1-3 %). Comparative 16S rRNA gene analysis indicated that strain SCSIO 72103^T had the highest similarities to Flavobacterium baculatum SNL9^T (94.7 %) and Myroides aquimaris SW105^T (94.2 %). Phylogenetic analysis based 16S rRNA gene sequences showed that strain SCSIO 72103^T formed a single clade with M. aquimaris SW105^T. Strain SCSIO 72103^T contained iso-C_{15 : 0} as the major fatty acid and the predominant respiratory quinone was menaquinone MK-6. These characteristics are consistent with those of F. baculatum SNL9^T and M. aquimaris SW105^T. Phosphatidylethanolamine, most notably, unidentified aminolipid and unidentified aminophospholipid were major polar lipids. Strain SCSIO 72103^T had a single circular chromosome of 2.96 Mb with a DNA G+C content of 35.1 mol%. The average nucleotide identity, average amino acid identity (AAI) and digital DNA-DNA hybridization values showed that the pairwise similarities between SCSIO 72103^T and the type strains of F. baculatum SNL9^T and M. aquimaris SW105^T were 78.5-80.5 %, 79.0-81.4 % and 22.7-22.8 %, respectively. The AAI values between species in this clade and the type species of Flavobacterium and Myroides were below the 65 % threshold, indicating that these species belong to a novel genus. On the basis of phylogenetic, physiological and chemotaxonomic characteristics, strain SCSIO 72103^T represents a new species of a novel genus, for which the name Paenimyroides aestuarii gen. nov. sp. nov. is proposed. The type strain is SCSIO 72103^T (=KCTC 92043^T=MCCC 1K06659^T). It is also proposed that nine known species in the genera Flavobacterium and Myroides are reclassified as Paenimyroides species.

Keywords: Paenimyroides aestuarii sp. nov.; polyphasic taxonomy; sediment.

MeSH terms

Amino Acids
Bacteria, Aerobic
Bacterial Typing Techniques
Base Composition
DNA, Bacterial / genetics
Estuaries*
Fatty Acids / chemistry
Flavobacterium* / genetics
Phylogeny
RNA, Ribosomal, 16S / genetics
Rivers
Sequence Analysis, DNA

Substances

RNA, Ribosomal, 16S
Fatty Acids
DNA, Bacterial
Amino Acids