Volume 10 Issue 1, January 2012

Two papers provide insight into the roles of the stringent response and H₂S in mediating antibiotic tolerance in genetically susceptible bacteria.

The erythrocyte surface protein basigin is identified as the receptor for Rh5 using a large-scale screen, and probably mediates invasion of allPlasmodium falciparumstrains.

P. gingivaliscan be viewed as a keystone pathogen owing to its disproportionately large impact on a microbial community relative to its abundance.

Sodalis glossinidiushas adapted the PhoPQ two-component system to establish and maintain symbiosis with its tsetse fly host.

Long-chainedS. pneumoniaeis more susceptible to complement-mediated killing.

A new study published inNature Geneticsreveals the parallel adaptive evolution of a bacterial pathogen during infection of humans and identifies new candidate pathogenicity genes.

This month's Genome Watch highlights new perspectives on polygenic adaptation and its consequences for fitness in microbial populations.

Our monthly round up of infectious diseases news, which this month includes the origin and spread of an amphibian assassin, turning the tide against HIV, and chicken pox-infected lollipops.

Bacteria need to find the middle of the cell and prevent the formation of a division septum that bisects the chromosome. The nucleoid occlusion system, mediated by Noc inBacillus subtilis and SlmA in Escherichia coli, connects septum formation with chromosome segregation to optimize cell division.

When a bacterium transitions from a free-living to a symbiotic lifestyle, the pressure to maintain certain genes decreases and the lack of genetic exchange allows deleterious mutations to accumulate. Here, McCutcheon and Moran describe the extraordinarily small genomes of several recently characterized symbionts and discuss the processes that allowed these genomes to shrink.

The nucleotide cyclic AMP is used by many organisms as a second messenger in signal transduction pathways to sense environmental changes. In this Review, McDonough and Rodriguez discuss the many roles of cAMP in bacterial and eukaryotic pathogens, from the regulation of virulence to the manipulation of host defences.

Dispersal is an essential stage in the 'life cycle' of many bacterial biofilms and is carefully regulated. McDougaldet al. describe the factors that control this step, and place this process in an ecological context with a comparison to analogous eukaryotic life cycles.

Capping the 5′ end of eukaryotic mRNAs with a 7-methylguanosine moiety enables efficient splicing, nuclear export and translation of mRNAs, and also limits their degradation by cellular exonucleases. Here, Canard and colleagues describe how viruses synthesize their own mRNA cap structures or steal them from host mRNAs, allowing efficient synthesis of viral proteins and avoidance of host innate immune responses.

The genomics era has provided the opportunity for detailed investigations into the effects of the gut microbiota on the host mucosa. Bron, van Baarlen and Kleerebezem describe the features of probiotic bacteria that affect the mucosal immune system, and discuss the effect of the molecular characteristics of the host's mucosa on the response to these bacteria.