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2025 Vol.37, Issue 4 Preview Page

Research Article

Genomic and Phenotypic Characterization of Enterobacter sp. MALB-1 Isolated from Monochamus alternatus for Plant Growth-Promoting Potential and Safety Assessment
Gang Hoon Lee1†
,
Jun Ho Lee1†
,
Tae Yun Choi1
,
Seo Jun Lee2
,
Saeyoull Cho3*
1MS Student, Department of Plant Medicine, College of Agriculture and Life Science, Kangwon National University, Chuncheon, 24341, Korea
2Undergraduate Student, Department of Plant Medicine, College of Agriculture and Life Science, Kangwon National University, Chuncheon, 24341, Korea
3Professor, Department of Plant Medicine, College of Agriculture and Life Science, Kangwon National University, Chuncheon, 24341, Korea
*Corresponding Author
†These authors contributed equally to this work.
31 December 2025. pp. 404-416
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Abstract

In this study, we isolated a plant growth-promoting bacterium, designated Enterobacter sp. MALB-1, from the gut of Monochamus alternatus. A polyphasic taxonomic approach demonstrated that while MALB-1 belongs to the genus Enterobacter, it represents a genetically and phenotypically distinct lineage. Whole-genome analysis revealed average nucleotide identity (ANI) values of 86.7－88.2% and digital DNA-DNA hybridization (dDDH) values of 31.8－34.7% with closely related type strains, which are significantly below the thresholds for species delineation. Genomic functional annotation identified a diverse repertoire of genes involved in nitrogen fixation, phosphate solubilization, and indole-3-acetic acid (IAA) biosynthesis, highlighting its potential as a biofertilizer. Phenotypically, MALB-1 exhibited robust adaptability to agricultural stress conditions, including broad pH (5－9) and salinity tolerance (0－5%), and possessed a versatile metabolic profile capable of utilizing various root exudate components. Importantly, a comprehensive safety assessment was conducted to address concerns regarding the opportunistic pathogenicity of the genus. Although genomic screening detected putative virulence factors and antibiotic resistance genes, phenotypic susceptibility assays confirmed that MALB-1 is susceptible to key therapeutic antibiotics, including ampicillin, kanamycin, and norfloxacin. This distinctive susceptibility profile, in stark contrast to the multidrug-resistant phenotypes of related Enterobacter strains, suggests a manageable safety risk. Collectively, these findings position Enterobacter sp. MALB-1 as a promising, safe, and efficient candidate for agricultural application.

Keywords
Biofertilizer
Enterobacter sp.
Plant growth-promoting bacterium
Safety assessment
Whole genome sequencing
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Information
  • Publisher :Agriculture and Life Sciences Research Institute, Kangwon National University
  • Publisher(Ko) :None
  • Journal Title :Journal of Agricultural, Life and Environmental Sciences
  • Volume : 37
  • No :4
  • Pages :404-416
  • Received Date : 2025-11-27
  • Revised Date : 2025-12-01
  • Accepted Date : 2025-12-01
  • DOI :https://doi.org/10.22698/jales.20250033
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