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In the pursuit of cultivating anaerobic anoxygenic phototrophs with unusual absorbance spectra, a purple sulfur bacterium was isolated from the shoreline of Baltrum, a North Sea island of Germany. It was designated strain 970, due to a predominant light harvesting complex (LH) absorption maximum at 963–966 nm, which represents the furthest infrared-shift documented for such complexes containing bacteriochlorophyll a. A polyphasic approach to bacterial systematics was performed, comparing genomic, biochemical, and physiological properties. Strain 970 is related to Thiorhodovibrio winogradskyi DSM 6702T by 26.5, 81.9, and 98.0% similarity via dDDH, ANI, and 16S rRNA gene comparisons, respectively. The photosynthetic properties of strain 970 were unlike other Thiorhodovibrio spp., which contained typical LH absorbing characteristics of 800–870 nm, as well as a newly discovered absorption band at 908 nm. Strain 970 also had a different photosynthetic operon composition. Upon genomic comparisons with the original Thiorhodovibrio strains DSM 6702T and strain 06511, the latter was found to be divergent, with 25.3, 79.1, and 97.5% similarity via dDDH, ANI, and 16S rRNA gene homology to Trv. winogradskyi, respectively. Strain 06511 (=DSM 116345T) is thereby described as Thiorhodovibrio litoralis sp. nov., and the unique strain 970 (=DSM 111777T) as Thiorhodovibrio frisius sp. nov.

The genus Corynebacterium is frequently found in the female urinary microbiome (FUM). In-depth characterization of Corynebacterium at the species level has been barely exploited. During ongoing FUM research studies, eight strains (c8Ua_144T, c8Ua_172T, c8Ua_174T, c8Ua_181T, c9Ua_112T, c19Ua_109T, c19Ua_121T, and c21Ua_68T) isolated from urine samples of healthy women or diagnosed with overactive bladder could not be allocated to any valid Corynebacterium species. In this work, we aimed to characterize these strains based on a polyphasic approach. The strains were Gram stain positive, rod to coccoid shaped, nonmotile, catalase positive, and oxidase negative. Phylogenetic analysis based on 16S rRNA and rpoB gene sequences indicated that all strains belonged to the genus Corynebacterium. The average nucleotide identity and digital DNA–DNA hybridization values among the genomes of the above eight strains and closely related type strains of the Corynebacterium genus were 18:1ω9c. Corynebacterium lehmanniae (c8Ua_144T = DSM 113405T = CCP 74T), Corynebacterium meitnerae (c8Ua_172T = DSM 113406T = CCP 75T), Corynebacterium evansiae (c8Ua_174T = DSM 113407T = CCP 76T), Corynebacterium curieae (c8Ua_181T = DSM 113408T = CCP 77T), Corynebacterium macclintockiae (c9Ua_112T = DSM 113409T = CCP 78T), Corynebacterium hesseae (c19Ua_109T = DSM 113410T= CCP 79T), Corynebacterium marquesiae (c19Ua_121T = DSM 113411T = CCP 80T), and Corynebacterium yonathiae (c21Ua_68T = DSM 113412T = CCP 81T) are proposed. This study evidenced that commonly used methodologies on FUM research presented limited resolution for discriminating Corynebacterium at the species level. Future research studying the biological mechanisms of the new Corynebacterium species here described may shed light on their possible beneficial role for healthy FUM.