Peribacillus castrilensis sp. nov.: A Plant-Growth-Promoting and Biocontrol Species Isolated From a River Otter in Castril, Granada, Southern Spain

Miguel Rodríguez; José Carlos Reina; Inmaculada Sampedro; Inmaculada Llamas; Fernando Martínez-Checa

doi:10.3389/fpls.2022.896728

Peribacillus castrilensis sp. nov.: A Plant-Growth-Promoting and Biocontrol Species Isolated From a River Otter in Castril, Granada, Southern Spain

Front Plant Sci. 2022 Jun 23:13:896728. doi: 10.3389/fpls.2022.896728. eCollection 2022.

Authors

Miguel Rodríguez¹, José Carlos Reina¹, Inmaculada Sampedro¹, Inmaculada Llamas^{1

2}, Fernando Martínez-Checa^{1

2}

Affiliations

¹ Department of Microbiology, Faculty of Pharmacy, University of Granada, Granada, Spain.
² Biomedical Research Centre (CIBM), Institute of Biotechnology, University of Granada, Granada, Spain.

Abstract

A strictly aerobic, chemoheterotrophic, endospore-forming, Gram-positive, rod-shaped bacterial strain N3^T was isolated from the feces of a river otter in Castril (Granada, southern Spain). It is halotolerant, motile, and catalase-, oxidase-, ACC deaminase-, and C4- and C8-lipase-positive. It promotes tomato plant growth and can reduce virulence in Erwinia amylovora CECT 222^T and Dickeya solani LMG 25993^T through interference in their quorum-sensing systems, although other antagonistic mechanisms could also occur. A phylogenetic analysis of the 16S rRNA gene sequence as well as the phenotypic and phylogenomic analyses indicated that the strain N3^T is a novel species of the genus Peribacillus, with the highest 16S rRNA sequence similar to that of Bacillus frigoritolerans DSM 8801^T (99.93%) and Peribacillus simplex DSM 1321^T (99.80%). Genomic digital DNA-DNA hybridization (dDDH) between the strain N3^T and Bacillus frigoritolerans DSM 8801^T and Peribacillus simplex was 12.8 and 69.1%, respectively, and the average nucleotide identity (ANIb) of strain N3^T and Bacillus frigoritolerans DSM 8801^T and Peribacillus simplex was 67.84 and 93.21%, respectively. The genomic G + C content was 40.3 mol%. Its main cellular fatty acids were anteiso-C_15:0 and iso-C_15:0. Using 16S rRNA phylogenetic and in silico phylogenomic analyses, together with the chemotaxonomic and phenotypic data, we demonstrated that the type strain N3^T (=CECT 30509^T = LMG 32505^T) is a novel species of the genus Peribacillus and the name Peribacillus castrilensis sp. nov. is proposed.

Keywords: Peribacillus castrilensis; new species; phytopathogen; plant-growth promoting species; quorum quenching; river otter.