Volume 10 Issue 10, October 2012

Poxviruses use a genomic accordion to stay abreast in the arms race with host cell defences.

Inflammation of the gut results in an altered microbiota and enriches for colibactin-producingE. coli, which promotes colorectal cancer.

TheL. monocytogenescompetence system has a key role in phagosomal escape, and activation of this system is controlled by a prophage excision event.

E. coliregulates cell size and growth rate in response to nutrient availability by altering fatty acid biosynthesis and, therefore, expansion of the cell envelope.

C. albicansinvades oral epithelial cells by interacting with host proteins EGFR and HER2.

The effector CRN8 is an active kinase that is secreted into the plant byP. infestansto enhance virulence.

HIV-infected CD4⁺T cells have a reduced rate of migration and an elongated morphology, which might represent a strategy for direct cell-to-cell transfer of the virus.

This month's Genome Watch describes two recent studies that used metagenomic data to characterize the role of the human gut microbiota in disease.

SAMHD1 has emerged as a novel HIV restriction factor that inhibits viral replication by limiting dNTP availability. Here, Schwartz and colleagues discuss the studies that led to the identification and characterization of SAMHD1, and speculate on why HIV-1 does not encode the SAMHD1-targeting protein, Vpx.

The two commercially available prophylactic vaccines that target human papilloma virus type 16 (HPV16) and HPV18 have proved extremely effective. Here, Schiller and Lowy summarize the characteristics of both the vaccines and HPV that have contributed to this success and speculate on whether or not this information could be used to direct the development of vaccines against other sexually transmitted viruses.

Fungal heat shock protein 90 (Hsp90) is an essential chaperone that regulates a range of cellular processes by ensuring the correct folding of a specific group of client proteins. In this Review, Brown and colleagues describe the roles and regulation of Hsp90 and discuss how it acts as a biological transistor to modulate fungal signalling networks.

Many bacteria and archaea synthesize intracellular gas-filled proteinaceous structures known as gas vesicles to act as flotation devices in aqueous environments. Here, Felicitas Pfeifer describes the basic properties of these interesting structures, the proteins that form them, the gene clusters that encode them and the regulation of their production.

In this Opinion article, Hajishengallis and colleagues propose that certain low-abundance microorganisms, termed 'keystone pathogens', can disrupt a normally benign commensal microbiota, leading to a microbial community structure that is associated with the development of disease.