R. Craig MacLean

Fitness costs of antibiotic resistance mutations in rich media do not reliably predict those in infection-like environments

The study shows that fitness costs of antibiotic resistance mutations in rich media do not reliably predict their costs in infection-like environments, with increased costs in lung-mimicking media and reduced prevalence in urinary tract-mimicking media.

Conjugation structures plasmid populations through host-lineage restriction

The paper quantifies host-lineage restriction of plasmid backbones in E. coli isolates and shows how this restriction structures plasmid co-occurrence.

Competition constrains parasite adaptation to thermal heterogeneity

This study shows that competition reduces thermal adaptation in bacteriophages under fluctuating temperatures compared to monoculture conditions.

DNA-damaging combination treatments impose genotype-specific constraints on hypermutator evolvability

This study shows that combining DNA-damaging agents with antibiotics can reduce resistance evolution in specific hypermutator bacterial genotypes but not others.

Trade-offs between phage resistance and conjugative ability shape the ecological and evolutionary response of a multidrug resistance plasmid to plasmid-dependent phage

This study shows that multidrug resistance plasmids face a trade-off between phage resistance and conjugative ability, which affects their evolutionary response to plasmid-dependent phages.

Evolutionary rescue accelerates competitive exclusion in a parasite community

This study shows evolutionary rescue prevents parasite extinction but can destabilize communities by promoting competitive exclusion in a viral parasite system under thermal stress.

Plasmids link antibiotic resistance genes and phage defense systems in E. coli

The paper analyzes 2,559 E. coli plasmids to show that antibiotic resistance genes and phage defense systems are physically linked, suggesting potential interactions between antibiotic use and phage therapy.

Chromosomal capture of beneficial genes drives plasmids towards ecological redundancy

The paper compares the fitness effects of chromosomal and plasmid genes in Rhizobium leguminosarum, finding that plasmids are depleted in beneficial genes, especially ancient ones, suggesting evolutionary pressure drives beneficial genes to the chromosome.

Adaptation of Pseudomonas aeruginosa to repeated invasion into a commensal competitor

This study examines how Pseudomonas aeruginosa adapts to repeated invasion of Staphylococcus epidermidis, showing divergent evolutionary responses between monoculture and coculture conditions.

CRISPR-Cas systems restrict horizontal gene transfer in Pseudomonas aeruginosa

This study shows CRISPR-Cas systems in Pseudomonas aeruginosa limit horizontal gene transfer by targeting phage and conjugative elements, leading to smaller genomes and reduced GC content.