gen. nov., sp. nov., a Marine Alphaproteobacterium Isolated from the Pacific Red Alga : Phenotypic Characterization and Pan-Genome Analysis.

A novel Gram-staining negative, strictly aerobic, rod-shaped, and non-motile bacterium, designated strain 10Alg 79, was isolated from the red alga . A phylogenetic analysis based on 16S rRNA gene sequences placed the novel strain within the family , class , phylum , where the nearest neighbor was ZQ172 (97.33% of identity). However, a phylogenomic study clearly showed that strain 10Alg 79 forms a distinct evolutionary lineage at the genus level within the family combining with strains L1 8-17, KCTC 52189, and DSM 24677. The ANI, AAI, and dDDH values between them were 75.63-78.15%, 67.41-73.08%, and 18.8-19.8%, respectively. The genome comprises 3,754,741 bp with a DNA GC content of 62.1 mol%. The prevalent fatty acids of strain 10Alg 79 were C and C. The polar lipid profile consisted of phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, an unidentified aminolipid, an unidentified phospholipid and an unidentified lipid. A pan-genome analysis showed that the unique part of the 10Alg 79 genome consists of 13 genus-specific clusters and 413 singletons. The annotated singletons were more often related to transport protein systems, transcriptional regulators, and enzymes. A functional annotation of the draft genome sequence revealed that this bacterium could be a source of a new phosphorylase, which may be used for phosphoglycoside synthesis. A combination of the genotypic and phenotypic data showed that the bacterial isolate represents a novel species and a novel genus, for which the name gen. nov., sp. nov. is proposed. The type strain is 10Alg 79 (=KCTC 72611 = KMM 6723).