Genomic Analysis of Serratia plymuthica MBSA-MJ1: A Plant Growth Promoting Rhizobacteria That Improves Water Stress Tolerance in Greenhouse Ornamentals

Abstract

Water stress decreases the health and quality of horticulture crops by inhibiting photosynthesis, transpiration, and nutrient uptake. Application of plant growth promoting rhizobacteria (PGPR) can increase the growth, stress tolerance, and overall quality of field and greenhouse grown crops subjected to water stress. Here, we evaluated Serratia plymuthica MBSA-MJ1 for its ability to increase plant growth and quality of Petunia × hybrida (petunia), Impatiens walleriana (impatiens), and Viola × wittrockiana (pansy) plants recovering from severe water stress. Plants were treated weekly with inoculum of MBSA-MJ1, and plant growth and quality were evaluated 2 weeks after recovery from water stress. Application of S. plymuthica MBSA-MJ1 increased the visual quality and shoot biomass of petunia and impatiens and increased the flower number of petunia after recovery from water stress. In addition, in vitro characterizations showed that MBSA-MJ1 is a motile bacterium with moderate levels of antibiotic resistance that can withstand osmotic stress. Further, comprehensive genomic analyses identified genes putatively involved in bacterial osmotic and oxidative stress responses and the synthesis of osmoprotectants and vitamins that could potentially be involved in increasing plant water stress tolerance. This work provides a better understanding of potential mechanisms involved in beneficial plant-microbe interactions under abiotic stress using a novel S. plymuthica strain as a model.

Serratia plymuthica MBSA-MJ1 Increases Shoot Growth and Tissue Nutrient Concentration in Containerized Ornamentals Grown Under Low-Nutrient Conditions

“…Serratia plymuthica MBSA-MJ1 originated from a bacteria collection in the laboratory of Dr. Christopher Taylor ( Aly et al, 2007 ), although the environmental source of this strain is unknown. MBSA-MJ1 was recently evaluated for its ability to reduce Botrytis cinerea infection in Petunia × hybrida ( South et al, 2020 ) and to stimulate the growth of plants recovering from severe water stress ( Nordstedt and Jones, 2021 ).…”

“…Genome sequence data for S. plymuthica MBSA-MJ1 ( Nordstedt and Jones, 2021 ) were used to search for genes putatively involved in increasing nutrient availability, carbon and amino acid metabolism, and heavy metal resistance. Genome sequence data can be found in the National Center for Biotechnology Information data base accession # PRJNA669647.…”

“…Therefore, in this work, we have evaluated the model PGPR strain Serratia plymuthica MBSA-MJ1 for its ability to increase plant growth and tissue nutrient concentration of three economically important horticulture crop species produced with low fertilizer inputs. MBSA-MJ1 was previously evaluated for its ability to increase plant growth during recovery from severe water stress ( Nordstedt and Jones, 2021 ). In addition, we have characterized the in vitro and genomic characteristics of this PGPR to begin elucidating different putative mechanisms used to promote plant growth with an emphasis on nutrient availability.…”

Antibiotic resistance in plant growth promoting bacteria: A comprehensive review and future perspectives to mitigate potential gene invasion risks

“…However, the overall relative abundance of ARGs was no significant at the applied dose but the authors suggested that biofertilizers application should be evaluated over time as resistance transfer is time dependent ( Yang et al, 2022 ). Similarly, using genomic analysis, Nordstedt and Jones (2021) identified genes putatively involved in antibiotic resistance in the PGPR Serratia plymuthica MBSA-MJ1 namely chloramphenicol acetyltransferase ( cat ) gene providing resistance to chloramphenicol and six copies of the efflux pump responsible for tetracycline resistance ( stp ; Nordstedt and Jones, 2021 ). Other identified genes include those encoding for resistance to fosmidomycin ( fsr ), bicyclomycin ( bcr ), polymyxin ( arnABCD ), and β-lactam multi-drug resistance ( ampC , ampD, and ampR ).…”

Facultative bacterial symbionts from European Orius species: Evidence for an ancestral symbiotic association

“…csdCysteine desulfurase activity to help the biosynthesis of selenoproteins (Esaki andMihara, 2002) phea2_2 Prephenate biosynthesis(Khanapur et al, 2017) yfcq_2 Cell adhesion(Garbeva, van Elsas and de Boer, 2012)group_24 13Lipid metabolic process: oxidoreductase activity (Marques-Pereira, Proença and Morais, 2020)yfcs_2Cell wall organization and chaperone-mediated protein folding(Garbeva, van Elsas and de Boer, 2012)mdtn_3Xenobiotic transmembrane transporter activity(Nordstedt and Jones, 2021) ykfi Toxic component of a type IV toxin-antitoxin (TA) system(Wen et al, 2017) mdto Involved in resistance to puromycin, acriflavine and tetraphenylarsonium chloride(Sulavik et al, 2001) yhdj DNA binding and N-methyltransferase activity(Rajagopala et al, 2014) ytnp_2The hydrolase activity as defence strategy to compete other bacteria(Schneider et al, 2011) azor1 Azoreductase activity(Ryan et al, 2014) tsar Degradation of para-toluenesulfonate (TSA) as sole source of carbon and energy(Monferrer et al, 2010) lpfd Cell adhesion(Garbeva, van Elsas and de Boer, 2012) papc_2 Fimbrial usher porin activity and identical protein binding(Omattage et al, 2018) iucc Siderophore biosynthetic process and ligase activity(Sibanda and Ramganesh, 2021) …”