Comparative genomics reveals key adaptive mechanisms in pathogen host-niche specialization

Area of Science:

• Microbiology
• Genomics
• Evolutionary Biology

Background:

• Host-microbe interactions are critical for bacterial adaptation and genome diversification.
• Understanding bacterial adaptation to new hosts is essential for managing host health and pathogen survival.

Purpose of the Study:

• To perform a comparative genomic analysis of bacterial pathogens across diverse hosts and environments.
• To identify genomic features, virulence factors, and antibiotic resistance genes associated with specific ecological niches.

Main Methods:

• Comparative genomic analysis of 4,366 bacterial genomes.
• Utilized bioinformatics databases and machine learning to identify genomic differences.
• Examined functional categories, virulence factors, and antibiotic resistance genes.

Main Results:

• Human-associated bacteria (Pseudomonadota) showed increased carbohydrate-active enzymes and immune-modulating virulence factors.
• Environmental bacteria (Bacillota, Actinomycetota) exhibited enrichment in metabolism and transcriptional regulation genes.
• Clinical bacteria had higher rates of antibiotic resistance genes, with animal hosts as reservoirs; the gene hypB was implicated in human-associated bacterial adaptation.

Conclusions:

• Bacterial pathogens display niche-specific genomic features and adaptive mechanisms.
• Findings provide insights into host-pathogen interactions, informing infection control and antibiotic stewardship.