Pseudomonas wadenswilerensis sp. nov. and Pseudomonas reidholzensis sp. nov., two novel species within the Pseudomonas putida group isolated from forest soil

Abstract

Within the frame of a biotechnological screening, we isolated two Pseudomonas strains from forest soil. 16S rRNA gene sequence analysis indicated that strain CCOS 864T shared 99.8 % similarity with Pseudomonas donghuensis HYST, while strain CCOS 865T shared 99.0 % similarity with Pseudomonas putida DSM 291T and lower similarity with other P. putida group type strains. Based on multilocus sequence analysis, the two strains were genotypically distinct from each other, each forming a separate clade. Strains CCOS 864T and CCOS 865T were Gram-stain-negative, motile and rod-shaped, growing at a temperature range of 4-37 °C. Strain CCOS 864T could be phenotypically distinguished from P. putida group species by the combination of gelatinase-positive reaction and positive growth on N-acetyl-d-glucosamine, p-hydroxyphenylacetic acid and inosine but lack of fluorescein production on King's B medium, while strain CCOS 865T could be distinguished from P. putida group species by the combination of positive growth with saccharic acid and negative growth with p-hydroxyphenylacetic acid and l-pyroglutamic acid. The major polar lipid for both strains was phosphatidylethanolamine; the major quinone was ubiquinone Q-9. DNA-DNA hybridization and average nucleotide identities confirmed the novel species status for the two strains. The DNA G+C contents of CCOS 864T and CCOS 865T were 62.1 and 63.8 mol%, respectively. The phenotypic, phylogenetic and DNA-DNA relatedness data support the suggestion that CCOS 864T and CCOS 865T represent two novel Pseudomonas species. The names Pseudomonas wadenswilerensis sp. nov. (type strain CCOS 864T=LMG 29327T) and Pseudomonas reidholzensis sp. nov. (type strain CCOS 865T=LMG 29328T) are proposed.

Comparative Genomic Analysis of the Biotechnological Potential of the Novel Species Pseudomonas wadenswilerensis CCOS 864T and Pseudomonas reidholzensis CCOS 865T

“…Investigation of the pan-genome revealed that P. wadenswilerensis CCOS 864 T has a complete gene set for p-HPA degradation ( Figure 3A), which was absent from the genome of P. reidholzensis CCOS 865 T . Positive growth of P. wadenswilerensis CCOS 864 T with this compound was obtained before [16], supporting our findings from the genomes. The hpaBC genes for degradation of p-HPA to homoprotocatechuic acid (HPC) and the hpaAG1G2EDF-nicT-hpaHIR gene cluster for the degradation from HPC to succinyl-CoA and acetyl-CoA by meta-cleavage [35,37] were found in the genome of P. wadenswilerensis CCOS 864 T .…”

“…The presence of both p-HPA degradation gene clusters was confirmed for 15 of 43 members of the P. putida group (Figure 2). Comparative genomic results of this feature matched with the phenotypical results obtained before for strains that were tested in their studies [16,38]. In comparison to the cluster in P. wadenswilerensis CCOS 864 T , the cluster in P. entomophila L48 T differed by the absence of the putative metabolite transport protein nicT, while in Pseudomonas sp.…”

“…However, closer inspection of the region downstream of crtI showed the presence of alternative crtBZ orthologs with lower sequence identity at this location (Figure 4). Although the presence of a complete gene cluster, a yellow color, indicating the synthesis of this carotenoid, was not observed phenotypically for P. reidholzensis CCOS 865 T [16]. Therefore, it might be possible that it is only weak or not at all expressed in P. reidholzensis CCOS 865 T under the tested conditions.…”

“…In particular, zeaxanthin showed promising effects against human cancer cells [79,80]. However, due to the missing phenotypical manifestation [16], the activity of the carotenoid biosynthesis genes for potential biocatalysis must be studied in more details.…”

7‐hydroxytropolone is the main metabolite responsible for the fungal antagonism of Pseudomonas donghuensis strain SVBP6

“…On the basis of their 16S rDNA sequences, the strains harbouring the orthologous cluster are representatives of P. donghuensis (HYS, P482, Irchel 3F5, 1239, ABAC8, NBRC 111117 and RIT263), P. qingdaonensis (JJ3, BIGb0473, PA14H7, 1033, MF6396, BRM28 and UASWS0946) and P. wadenswilerensis (SNU WT1), being the three of them recently described species within the broad P. putida group (Gao et al, 2015;Frasson et al, 2017;Wang et al, 2019) (Fig. S1).…”