Salinimonas marina sp. nov. Isolated from Jeju Island Marine Sediment

A Gram-stain-negative, rod-shaped, and strictly aerobic bacterium designated strain G2-b^T was isolated from the marine sediment around Jeju Island, South Korea. Strain G2-b^T was found to be catalase- and oxidase-positive, white-pigmented, motile with polar flagellum, and to grow optimally at 25 °C, pH 7.0 in the presence of 4% (w/v) NaCl. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that strain G2-b^T belongs to the genus Salinimonas and was closely related Salinimonas sediminis N102^T (96.7% sequence similarity), Salinimonas iocasae KX18D6^T (95.4%), Salinimonas lutimaris DPSR-4^T (94.7%), and Salinimonas chungwhensis BH030046^T (94.6%). Strain G2-b^T possessed ubiquinone 8 as the sole respiratory quinone, summed feature 3 and summed feature 8 as the major fatty acids, and phosphatidylethanolamine and phosphatidylglycerol as the major polar lipids. The genome size and G + C content of the strain G2-b^T were determined to be 3,765,169 bp, and 49.7%, respectively, as a complete circular genome. Based on the genomic analyses (e.g., average nucleotide identity and digital DNA-DNA hybridization), the strain G2-B^T likely represents a new species in the genus Salinimonas, for which we propose to name this novel bacterium Salinimonas marina sp. nov., and the type strain is designated G2-B^T (= KCTC 72817^T = VTCC 910110^T).

Description of three new Alteromonas species Alteromonas antoniana sp. nov., Alteromonas lipotrueae sp. nov. and Alteromonas lipotrueiana sp. nov. isolated from marine environments, and proposal for reclassification of the genus Salinimonas as Alteromonas

In the course of a bioprospective study of marine prokaryotes for cosmetic purposes, four strains, MD_567^T, MD_652^T, MD_674 and PS_109^T, were isolated that 16S rRNA gene affiliation indicated could represent three new species within the family Alteromonadaceae. A thorough phylogenetic, genomic and phenotypic taxonomic study confirmed that the isolates could be classified as three new taxa for which we propose the names Alteromonas antoniana sp. nov., Alteromonas lipotrueae sp. nov. and Alteromonas lipotrueiana sp. nov. In addition, the consistent monophyletic nature of the members of the genera Alteromonas and Salinimonas showed that both taxa should be unified, and therefore we also propose the reclassification of the genus Salinimonas within Alteromonas, as well as new combinations for the species of the former. As the specific epithets profundi and sediminis are already used for Alteromonas species, we created the nomina nova "Alteromonas alteriprofundi" nom. nov. and Alteromonas alterisediminis nom. nov. to accommodate the new names for "Salinimonas profundi" and Salinimonas sediminis. Whole genome comparisons also allowed us to detect the unexpected codification of aromatic hydrocarbon biodegradative compounds, such as benzoate and catechol, whose activity was then demonstrated phenotypically. Finally, the high genomic identity between the type strains of Alteromonas stellipolaris and Alteromonas addita indicated that the latter is a junior heterotypic synonym of Alteromonas stellipolaris.

Complete genome sequence of a piezophilic bacterium Salinimonas sediminis N102T, isolated from deep-sea sediment of the New Britain Trench

Salinimonas sediminis N102^T is a cold-adapted, slightly halophilic piezophile isolated from deep-sea sediment (4700 m) of the New Britain Trench. In this study, we report the complete genome sequence of S. sediminis N102^T, which is comprised of 4,440,293 base pairs with a mean G + C content of 48.2 mol%. The complete genome harbors 3851 predicted protein-coding genes, 70 tRNA genes and 15 rRNA genes. Abundant genes in the genome were predicted to be linked to bacterial deep-sea lifestyle. The complete genome sequence of S. sediminis N102^T provides insights into the microbial adaptation strategies to the deep-sea environment.

Salinimonas iocasae sp. nov., a halophilic bacterium isolated from a polychaete tube in a hydrothermal field

A moderately halophilic bacterium, designated strain KX18D6T, was isolated from the tube of the polychaete Paralvinella hessleri collected from a hydrothermal field located in the Okinawa Trough. Strain KX18D6T was Gram-stain-negative, rod-shaped, facultatively anaerobic, motile, oxidase- and catalase-positive, and grew optimally at 30–35 °C, pH 7.0 and in the presence of 3–5 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain KX18D6T grouped with the members of the genus Salinimonas , including Salinimonas chungwhensis BH030046T (97.7 % sequence similarity), Salinimonas lutimaris DPSR-4T (97.2 %) and Salinimonas sediminis N102T (96.4 %). Genome sequencing of strain KX18D6T revealed a genome size of 4.16 Mb and a DNA G+C content of 47.3 mol%. Genomic average nucleotide identity (orthoANI) values of strain KX18D6T with S. chungwhensis DSM 16280T, S. lutimaris KCTC 23464T and S. sediminis N102T were 76.2, 73.1 and 73.2 %, respectively, while the in silico DNA–DNA hybridization (GGDC) values for strain KX18D6T with these strains were 25.3, 17.7 and 18.0 %, respectively. The major fatty acids were summed feature 3 (C16 : 1 ω7c/C16 : 1 ω6c), C16 : 0 and summed feature 8 (C18 : 1 ω7c/C18 : 1 ω6c). The predominant respiratory quinone was ubiquinone 8, and the predominant polar lipids were phosphatidylethanolamine and phosphatidylglycerol. On the basis of comparative analysis of phylogenetic, phylogenomic, phenotypic and chemotaxonomic characteristics, strain KX18D6T (=KCTC 72464T=MCCC 1K03884T) is clearly distinguishable from the type strains of species of the genus Salinimonas and is considered to represent a novel species of the genus Salinimonas , for which the name Salinimonas iocasae sp. nov. is proposed.

Alteromonas indica Lin et al. 2018 is a later heterotypic synonym of Salinimonas sediminis Cao et al. 2018

Alteromonas indica IO390401^T was compared with Salinimonas sediminis N102^T to examine the taxonomic relationship between the two type strains. The 16S rRNA gene sequence of A. indica IO390401^T shared high similarity (99.9 %) with that of S. sediminis N102^T. The results of phylogenetic analyses based on 16S rRNA gene sequences indicated that the two strains formed a tight cluster within the genus Salinimonas. Whole genomic comparison between the two strains revealed an average nucleotide identity of 99.2 % and a digital DNA-DNA hybridization estimate of 92.6 %, strongly indicating that the two strains represented a single species. In addition, neither strain displayed any striking difference in metabolic, physiological or chemotaxonomic features. Therefore, we propose Alteromonas indica as a later heterotypic synonym of Salinimonas sediminis.