# Description of Pseudomonas stagnisoli sp. nov. and Pseudomonas cimarronensis sp. nov., isolated from freshwater sediments

## TL;DR

Two new species of Pseudomonas bacteria were discovered in freshwater sediments and named Pseudomonas stagnisoli and Pseudomonas cimarronensis.

## Contribution

The paper introduces two novel Pseudomonas species based on genomic and taxonomic analysis of freshwater sediment isolates.

## Key findings

- Strains P3C3T and MAC6T form distinct branches within the Pseudomonas genus based on phylogenetic analysis.
- Genomic data shows the strains have average nucleotide identity and DNA-DNA hybridization values below species-level thresholds.
- The two strains differ in optimal growth conditions and genomic characteristics.

## Abstract

A polyphasic taxonomic approach was employed to characterize two novel strains, P3C3T and MAC6T, isolated from sediments of the Innovation Way Drive Pond (Stillwater, OK) and the Cimarron River (Perkins, OK), respectively. Both strains were strictly aerobic, Gram-stain-negative, rod-shaped, motile and non-spore-forming bacteria. Strain P3C3T grew optimally at 35 °C, pH 6.0 and 0.5% (v/w) NaCl, while strain MAC6T grew optimally at 30 °C, pH 6.0 and 4.0% (v/w) NaCl. Based on 16S rRNA gene sequence similarity, P3C3T was most closely related to Pseudomonas alcaligenes (98.3%), whereas MAC6T was most closely related to Pseudomonas anguilliseptica (98.6%). Phylogenetic analysis using the 16S rRNA gene and whole-genome phylogenomic analysis indicated that P3C3T and MAC6T formed distinct branches within the Pseudomonas genus. Additionally, overall genomic-based relatedness indices demonstrated that P3C3T and MAC6T and the type strains of close relatives shared average nucleotide identity and digital DNA–DNA hybridization values <95% and <70%, respectively, which are below the currently accepted thresholds for species-level delineation. The genomes of strains P3C3T and MAC6T were 4.3 and 4.2 Mbp, respectively, with G+C contents of 64.5 and 60.5 mol%. Based on polyphasic taxonomic criteria, P3C3T and MAC6T represent two novel species within the genus Pseudomonas, for which the names Pseudomonas stagnisoli and Pseudomonas cimarronensis sp. nov. are proposed. The type strains are P3C3T (=CCM 9468T=CECT 31230T=DSM 119661T) and MAC6T (=CCM 9470T=CCUG 78313T=CECT 31231T), respectively.