Microbacterium zeae sp. nov., an endophytic bacterium isolated from maize stem

Area of Science:

• Microbiology
• Bacteriology
• Plant-associated microbes

Background:

• The genus Microbacterium comprises diverse Gram-positive bacteria found in various environments.
• Characterizing novel bacterial species is crucial for understanding microbial diversity and ecological roles.

Purpose of the Study:

• To isolate and characterize a novel bacterial strain from maize stem tissue.
• To determine the taxonomic position of the novel isolate within the genus Microbacterium.

Main Methods:

• Polyphasic taxonomic study including 16S rRNA gene sequencing.
• DNA-DNA hybridization (DDH) to assess genetic relatedness.
• Analysis of chemotaxonomic markers (fatty acids, menaquinone, polar lipids).
• Physiological and biochemical characterization.

Main Results:

• A novel Gram-positive, aerobic, rod-shaped bacterium, strain 1204^T, was isolated from maize.
• 16S rRNA gene sequence analysis indicated affiliation with the genus Microbacterium, with high similarity to M. enclense and M. proteolyticum.
• DNA-DNA hybridization values were below the threshold for species delineation (<70%).
• Distinct chemotaxonomic profiles (major fatty acids, polar lipids) and biochemical characteristics differentiated strain 1204^T from related species.
• DNA G+C content was 68.0 mol%.

Conclusions:

• Strain 1204^T represents a novel species within the genus Microbacterium.
• The proposed name for this new species is Microbacterium zeae sp. nov.
• The type strain is 1204^T (=CGMCC 1.15289 = DSM 100750).