Martelella lutilitoris sp. nov., isolated from a tidal mudflat

Area of Science:

• Microbiology
• Marine Biology
• Genomics

Background:

• The genus Martelella comprises Gram-negative bacteria with limited described species.
• Marine environments, particularly coastal mudflats, are rich sources of novel microbial diversity.
• Understanding bacterial diversity in plant rhizospheres is crucial for ecological studies.

Purpose of the Study:

• To isolate and characterize a novel bacterium from a marine plant rhizosphere.
• To determine the taxonomic placement of the novel isolate using polyphasic characterization.
• To propose a new species within the genus Martelella.

Main Methods:

• Isolation and cultivation of bacteria from Carex scabrifolia rhizosphere mudflat.
• Physiological and biochemical characterization (Gram staining, oxidase, catalase, growth conditions).
• Genomic analysis (genome size, G+C content) and phylogenetic analysis (16S rRNA gene sequencing, DNA-DNA hybridization).

Main Results:

• A novel, strictly aerobic, non-flagellated, Gram-negative bacterium (GH2-6^T) was isolated.
• The isolate demonstrated optimal growth under specific salinity (0.5-3% NaCl), temperature (20-45°C), and pH (5-10) ranges.
• Phylogenetic analysis placed GH2-6^T within the genus Martelella, with distinct 16S rRNA gene sequence and DNA-DNA hybridization values differentiating it from known species.
• Genomic data revealed a genome size of 4.45 Mb and a G+C content of 61.9 mol%.

Conclusions:

• Strain GH2-6^T represents a novel species, proposed as Martelella lutilitoris sp. nov.
• The discovery expands the known diversity of the Martelella genus.
• This finding contributes to the understanding of microbial communities in marine rhizosphere ecosystems.