AUTHOR=Gutierrez-Albanchez Enrique , García-Villaraco Ana , Lucas José A. , Horche Ignacio , Ramos-Solano Beatriz , Gutierrez-Mañero F. J. 

TITLE=Pseudomonas palmensis sp. nov., a Novel Bacterium Isolated From Nicotiana glauca Microbiome: Draft Genome Analysis and Biological Potential for Agriculture

JOURNAL=Frontiers in Microbiology

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2021.672751

DOI=10.3389/fmicb.2021.672751

ISSN=1664-302X

ABSTRACT=<p>A novel <italic>Pseudomonas</italic>, designated strain BBB001<sup>T</sup>, an aerobic, rod-shaped bacterium, was isolated from the rhizosphere of <italic>Nicotiana glauca</italic> in Las Palmas Gran Canaria, Spain. Genomic analysis revealed that it could not be assigned to any known species of <italic>Pseudomonas</italic>, so the name <italic>Pseudomonas palmensis</italic> sp. nov. was proposed. A 16S rRNA gene phylogenetic analysis suggested affiliation to the <italic>Pseudomonas brassicae</italic> group, being <italic>P. brassicae</italic> MAFF212427 <sup>T</sup> the closest related type strain. Upon genomic comparisons of both strains, all values were below thresholds established for differentiation: average nucleotide identity (ANI, 88.29%), average amino acid identity (AAI, 84.53%), digital DNA-DNA hybridization (dDDH, 35.4%), and TETRA values (0.98). When comparing complete genomes, a total of 96 genes present exclusively in BBB001<sup>T</sup> were identified, 80 of which appear associated with specific subsystems. Phenotypic analysis has shown its ability to assimilate glucose, potassium gluconate, capric acid malate, trisodium citrate, and phenylacetic acid; it was oxidase positive. It is able to produce auxins and siderophores <italic>in vitro</italic>; its metabolic profile based on BIOLOG Eco has shown a high catabolic capacity. The major fatty acids accounting for 81.17% of the total fatty acids were as follows: C<sub>16:0</sub> (33.29%), summed feature 3 (22.80%) comprising C<sub>16:1</sub> ω7<italic>c</italic> and C<sub>16:1</sub> ω6<italic>c</italic>, summed feature 8 (13.66%) comprising C<sub>18:1</sub> ω7<italic>c</italic>, and C<sub>18:1</sub>ω6<italic>c</italic> and C<sub>17:0</sub> cyclo (11.42%). The ability of this strain to improve plant fitness was tested on tomato and olive trees, demonstrating a great potential for agriculture as it is able to trigger herbaceous and woody species. First, it was able to improve iron nutrition and growth on iron-starved tomatoes, demonstrating its nutrient mobilization capacity; this effect is related to its unique genes related to iron metabolism. Second, it increased olive and oil yield up to 30% on intensive olive orchards under water-limiting conditions, demonstrating its capacity to improve adaptation to adverse conditions. Results from genomic analysis together with differences in phenotypic features and chemotaxonomic analysis support the proposal of strain BBB001<sup>T</sup> (=LMG 31775<sup>T</sup> = NCTC 14418<sup>T</sup>) as the type strain of a novel species for which the name <italic>P. palmensis</italic> sp. nov is proposed.</p>