Anianabacter salinae gen. nov., sp. nov. ASV31T, a Facultative Alkaliphilic and Extremely Halotolerant Bacterium Isolated from Brine of a Millennial Continental Saltern

During a prokaryotic diversity study in Anana Salt Valley, a new Rhodobacteraceae member, designated ASV31(T), was isolated from Santa Engracia spring water. It was extremely halotolerant, tolerating up to 23% NaCl, and facultatively alkaliphilic, growing at pH 6.5-9.5 (optimum at 7.0-9.5). The isolate was a Gram-negative, rod-shaped, aerobic and non-motile bacterium that formed beige-to-pink colonies on marine agar. According to a 16S rRNA gene-based phylogenetic analysis, strain ASV31(T) forms a distinct branch of the family Rhodobacteraceae, with Thioclava pacifica DSM 10166(T) being its closest type strain (95.3%). This was confirmed with a phylogenomic tree and the values of ANI (73.9%), dDDH (19.3%), AAI (63.5%) and POCP (56.0%), which were below the genus/species level boundary. Additionally, an ability to degrade aromatic compounds and biosynthesise secondary metabolites was suggested by the genome of strain ASV31(T). Distinguishing fatty acid profiles and polar lipid content were also observed. The genome size was 3.6 Mbp, with a DNA G+C content of 65.7%. Based on the data obtained, it was considered that strain ASV31(T) (=CECT 30309(T) = LMG 32242(T)) represents a new species of a new genus in the family Rhodobacteraceae, for which the name Anianabacter salinae gen. nov., sp. nov. is proposed.

Automated summary

A new member of the Rhodobacteraceae family, named Anianabacter salinae, was isolated from Santa Engracia spring water during a prokaryotic diversity study in Anana Salt Valley. This bacterium exhibited extreme halotolerance and facultatively alkaliphilic characteristics. It formed a distinct branch within the Rhodobacteraceae family based on phylogenetic analysis.