Genotypic and Phenotypic Characterization of Pseudomonas atacamensis EMP42 a PGPR Strain Obtained from the Rhizosphere of Echinocactus platyacanthus (Sweet Barrel)

• Published in: Microorganisms (Basel) Vol. 12; no. 8; p. 1512
• Main Authors: Salinas-Virgen, Leilani Itzel, de la Torre-Hernández, María Eugenia, Aguirre-Garrido, José Félix, Martínez-Abarca, Francisco, Ramírez-Saad, Hugo César
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 24-07-2024; MDPI
• Subjects: Bacteria; Barrel plating; Cacti; Cloning; CRISPR; Echinocactus; Ecological niches; Fertilizers; Genera; Genes; Genetic structure; Genomes; genomics; Germination; Maximum likelihood method; New species; Operons; Oxidative stress; Parasarus atacamensis; PGPR; Plant bacterial diseases; Plant growth; Plasmids; Potassium; Pseudomonas; Pseudomonas atacamensis; Regulatory sequences; Rhizosphere; rRNA; Seedlings; Seeds; Substrates; Mexico; Pseudomonas atacamensis; PGPR; genomics
• ISSN: 2076-2607; 2076-2607
• DOI: 10.3390/microorganisms12081512

Plant growth-promoting rhizobacteria (PGPR) are a group of bacteria that associate with the rhizosphere of plants; one of the most abundant bacterial genera in this ecological niche is
, which is constantly expanding due to the emergence of new species such as
, whose discovery in 2019 has led to the characterization of several strains from different environments but taxonomically related. The objective of this work was to phenotypically and molecularly characterize
strain EMP42, isolated from the rhizosphere of
. The strain EMP42 is able to use different substrates and reduce oxidative stress in plants. It is capable of improving growth parameters such as the number of inflorescences and the height of the aerial body of
, as well as the germination and seedling survival of the cacti
and
. The genetic structure of
EMP42 consists of a closed chromosome of 6.14 Mbp, and 61.1% GC content. It has 5572 genes, including those associated with PGPR activities, such as the
ABCDE, SAP,
ABPRU and
ABC genes, among others, and three ncRNA loci, nine regulatory regions, five complete rRNA operons and three CRISPR-Cas loci, showing phylogenomic similarities with the reference strain
B21-026. Therefore, this study contributes to the understanding of genomic diversity within
and, particularly, highlights the potential application of strain EMP42 as a PGPR.