Microbacterium petrolearium sp. nov., isolated from an oil-contaminated water sample

Area of Science:

• Microbiology
• Environmental Science
• Bacterial Taxonomy

Background:

• Isolation of novel microorganisms from contaminated environments is crucial for understanding microbial diversity and developing bioremediation strategies.
• The Dagang Oilfield in China presents a unique ecosystem for studying extremophilic bacteria adapted to hydrocarbon pollution.

Purpose of the Study:

• To isolate and characterize a novel bacterial strain from an oil-contaminated site.
• To determine the taxonomic position of the novel isolate using polyphasic characterization, including phenotypic and genotypic analyses.
• To propose a new species name for the identified bacterium.

Main Methods:

• Isolation and cultivation of bacteria from oil-contaminated water samples.
• Gram staining, morphological, and physiological characterization (temperature, pH, NaCl tolerance).
• Cell wall composition analysis (diamino acid, sugars, glycan moiety).
• Respiratory quinone and polar lipid profiling.
• Fatty acid analysis.
• 16S rRNA gene sequencing and DNA-DNA hybridization for phylogenetic analysis.
• DNA G+C content determination.

Main Results:

• A Gram-positive, rod-shaped, aerobic bacterium, strain LAM0410(T), was isolated.
• The strain demonstrated broad growth ranges: 4–50 °C, pH 4.4–12.0, and up to 12% NaCl.
• Phylogenetic analysis based on 16S rRNA gene sequences placed the isolate within the genus Microbacterium.
• DNA-DNA hybridization values indicated low relatedness to closely related species, supporting its novelty.
• The DNA G+C content was determined to be 67.4 mol%.

Conclusions:

• Strain LAM0410(T) represents a novel species within the genus Microbacterium.
• The proposed name for this new species is Microbacterium petrolearium sp. nov.
• This discovery expands the known diversity of the Microbacterium genus and highlights its adaptation to extreme environments.