CRISPR–Cas regulates expression of embedded anti-phage defence systems - Nature

CRISPR–Cas systems transcriptionally tune diverse innate defences using CRISPR RNA-like guides to balance antiviral protection with fitness, and hyperactivate these defences when compromised, establis...

nature.com

The pQBR mercury resistance plasmids: a model set of sympatric environmental mobile genetic elements

Plasmids are extrachromosomal mobile genetic elements that can facilitate rapid bacterial adaptation by transferring genes between individuals. Whilst plasmids are known to exist in diverse habitats a...

microbiologyresearch.org

Expression of conjugation genes is controlled by a novel zipper-type transcriptional attenuation mechanism

Abstract. Proper expression of genes clustered in operons, particularly large operons, can be complex, often involving multiple regulatory switches. The co

academic.oup.com

Mobility shapes plasmid GC content evolution

Plasmids are frequently AT-rich relative to their bacterial hosts. Despite this tendency towards lower GC content, plasmid and host chromosome GC content are positively correlated across diverse collections of plasmid-host pairs. However, the evolutionary processes underlying this pattern remain unclear. The classic model of amelioration predicts that horizontally acquired DNA gradually converges on host nucleotide composition. However, because plasmids can repeatedly transfer between bacterial hosts, the opportunity for such host-associated evolution may depend on their transmission dynamics. Using 50,936 plasmid-host pairs from a public sequence database, we found that the apparent global correlation between plasmid and host chromosome GC content was largely driven by differences between bacterial species rather than within species. We therefore accounted for plasmid and host population structure when testing how plasmid mobility shaped host-associated compositional evolution. We compared two contrasting regimes: a population of 3,682 Enterobacterales plasmids distributed across diverse host backgrounds, and six long-term host-associated plasmids from a Rhizobium leguminosarum lineage with INSeq-determined gene essentiality data. In the Enterobacterales population, GC content variation was overwhelmingly explained by plasmid lineage rather than host phylogeny, and conjugative plasmids showed greater similarity to their host chromosomes than mobilisable or non-mobilisable plasmids. In the Rhizobium leguminosarum plasmids, synonymous-site composition was more similar to the host chromosome among genes required across multiple host life stages. Together, these results support a model in which plasmid mobility influences the opportunity for host-associated evolutionary processes to alter nucleotide composition. ### Competing Interest Statement The authors have declared no competing interest. Wellcome Trust, 319534/Z/24/Z St. John's College, University of Oxford, UK

doi.org

AllTheBacteria: a community resource empowers biology and discovers novel peptide antibiotics.

Published in bioRxiv : the preprint server for biology

doi.org

Characterizing the ecological niche of insertion sequences within prokaryotic genomes

Abstract. Insertion sequences (ISs) are widespread prokaryotic transposable elements, often regarded as genomic parasites that primarily cause deleterious

academic.oup.com

Widespread immune systems protect bacteria against conjugative plasmids

Conjugative plasmids are a class of mobile genetic elements capable of efficient transfer between bacterial cells. Although they can introduce beneficial traits such as antibiotic resistance to recipi...

biorxiv.org

Bacterial and human exonucleases mediate interkingdom antiviral immunity

All kingdoms of life have developed strategies to limit viral infection. In humans, interferons induce a suite of antiviral factors that collectively provide immunity. Some human immune genes are homo...

biorxiv.org

Mobile genetic elements shape microbial diversity and functions in thawing permafrost soils

Nature Microbiology, Published online: 29 June 2026; doi:10.1038/s41564-026-02391-7An 8-year soil meta-omic time series shows how mobile genetic elements shape permafrost microbial diversity and impact a range of functions, including carbon and nutrient cycling.

go.nature.com

Eco-evolutionary responses to plasmid-dependent phage constrain the spread of multidrug-resistance plasmids

Abstract. Phage therapy offers an alternative to antibiotics for treating multidrug-resistant infections. Plasmid-dependent phages (PDPs) are promising the

academic.oup.com

Life Identification Numbers: A strain nomenclature approach to aid epidemiological surveillance of bacterial pathogens

Unified bacterial strain taxonomies are needed for coherent communication of findings in microbiological research. This Essay provides an overview of a novel bacterial strain taxonomy and describes ho...

journals.plos.org

biorxiv.org

Researchers say the Trump administration is finding new ways to punish science

Even with federal grants largely restored, scientists say the Trump administration is still preventing those funds from reaching them. The consequences, they say, are already becoming clear.

npr.org

Eco-evolutionary responses to plasmid-dependent phage constrain the spread of multidrug resistance plasmids

Abstract. Phage therapy offers a promising alternative to antibiotics for treating multidrug-resistant infections. Plasmid-dependent phages (PDPs) are part

doi.org

biorxiv.org

Large extrachromosomal replicons are widespread across bacterial lineages and show coordinated replication termination and spatial coupling with the chromosome - Nature Communications

Bacterial genomes often include extrachromosomal replicons, ranging from small plasmids to chromosome-scale replicons. Here, Czarnecki et al. analyse more than 40,000 complete bacterial genomes and sh...

doi.org

uv.es

Diversity-generating retroelements for programmable targeted hypermutagenesis - Nature Biotechnology

Diversity-generating retroelements are engineered for directed evolution in E.coli.

nature.com

Mechanistic insights into plasmid transfer inhibition in Enterobacterales by nucleoside analogues - npj Antimicrobials and Resistance

npj Antimicrobials and Resistance - Mechanistic insights into plasmid transfer inhibition in Enterobacterales by nucleoside analogues

nature.com

Career Opportunities: Postdoctoral positions in predictive modelling of antibiotic resistance spread (22755)

tinyurl.com

Complex temporal dynamics of phage-bacteria populations in an animal-associated marine system - Nature Communications

It remains unclear how viral genomes remain relatively stable over time, given the rapid co-evolution seen within hosts. Here, authors explore complex marine phage-bacteria dynamics using over 1000 ph...

nature.com

International Symposium on Plasmid Biology 2026

plasmid-biology-2026.de