Shewanella nanhaiensis sp. nov., a marine bacterium isolated from sediment of South China Sea, and emended descriptions of Shewanella woodyi, Shewanella hanedai and Shewanella canadensis

Abstract

A Gram-stain-negative, motile, facultative anaerobic and rod-shaped bacterium, designated strain NR704-98T, was isolated from marine sediment of the northern South China Sea. Cells were positive for oxidase and catalase activity. Growth was observed at 4–30 °C (optimum 20–25 °C), at pH 6–9 (pH 7) and with 0.5–7 % NaCl (2 %). The 16S rRNA gene-based phylogenetic analysis revealed that the nearest phylogenetic neighbours of strain NR704-98T were Shewanella woodyi MS32T (97.9 %), Shewanella hanedai 281T (97.1 %), Shewanella sediminis HAW-EB3T (96.8 %) and Shewanella canadensis HAW-EB2T (96.7 %). Based on the results of phylogenomic analysis, the average nucleotide identity and the digital DNA–DNA hybridization values between strain NR704-98T and the previously mentioned type strains of species of the genus Shewanella were in the range of 74.9–93.1 % and 20.6–51.4 %, respectively. The respiratory quinones were Q-7 and Q-8. The predominant fatty acids (>10 %) of strain NR704-98T were C16 : 0, summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c) and iso-C15 : 0. Phosphatidylethanolamine, phosphatidylglycerol, two unidentified aminophospholipids and five unidentified lipids were detected in strain NR704-98T. Based on the phylogenetic and phenotypic characteristics, strain NR704-98T is considered to represent a novel species of the genus Shewanella , for which the name Shewanella nanhaiensis sp. nov. is proposed. The type strain is NR704-98T (=KCTC 82799T=MCCC 1K06091T).

Whole genome-based taxonomy of Shewanella and Parashewanella

“…Some of the novel species identified in our 381-genome dataset were described during 2021 but do not have a validly published name yet, except Shewanella nanhaiensis Cao et al . 2021, with the type strain designated NR704-98 T [29], validly published and included in the LPSN while writing this paper.…”

“…Our phylogenomic reconstructions supported the identification of 46 novel Shewanella species and 2 novel Parashewanella species among the sequenced isolates (Table1). Some of the novel species identified in our 381-genome dataset were described during 2021 but do not have a validly published name yet, except Shewanella nanhaiensisCao et al 2021, with the type strain designated NR704-98 T[29], validly published and included in the LPSN while writing this paper.A highly populated clade comprising diverse strains belonging to the same novel species is that formed by Shewanella putrefaciens 97 (MIS), Shewanella sp. M16, Shewanella sp.…”