Hot off the presses! Aug 01 Nat Rev Microbiol

The Aug 01 issue of the Nat Rev Microbiol is now up on Pubget (About Nat Rev Microbiol): if you're at a subscribing institution, just click the link in the latest link at the home page. (Note you'll only be able to get all the PDFs in the issue if your institution subscribes to Pubget.)

Latest Articles Include:

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  - Nat Rev Microbiol 9(8):557 (2011)
  
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  - Nat Rev Microbiol 9(8):558 (2011)
  
• Immunology: Virus and bacterium gang up on host | PDF (165 KB)
  - Nat Rev Microbiol 9(8):559 (2011)
  Infectious diseases caused by viruses such as influenza viruses are often followed by bacterial infection. Separately, these infections are not necessary lethal, but their combination results in higher mortality levels.
• Bacterial physiology: MreB takes a back seat | PDF (256 KB)
  - Nat Rev Microbiol 9(8):560 (2011)
  Bacterial cell shape is maintained by cell envelope peptidoglycan, which forms a three-dimensional network composed of glycan strands linked by peptide crossbridges. In rod-shaped bacteria, the cylindrical peptidoglycan wall is synthesized by macromolecular complexes containing synthetic enzymes (collectively known as penicillin-binding proteins) and the plasma membrane proteins MreC, MreD, RodA and RodZ.
• Parasitology: Leishmania turns down the heat | PDF (299 KB)
  - Nat Rev Microbiol 9(8):560 (2011)
  Millions of people worldwide are infected by parasites from the genus Leishmania; the severity of symptoms varies greatly, from deadly visceral infections to self-healing skin lesions, depending on the infecting species. However, the mechanisms behind the differences in pathogenicity of Leishmania spp.
• Virology | Phage biology | HIV | PDF (95 KB)
  - Nat Rev Microbiol 9(8):561 (2011)
  A genetically humanized mouse model for hepatitis C virus infection Dorner, M.et al. Nature 474, 208–211 (2011)
• Cellular microbiology: Bacterial pea shooters | PDF (139 KB)
  - Nat Rev Microbiol 9(8):562 (2011)
  Gram-negative bacteria produce outer membrane vesicles with roles in processes such as communication, pathogenesis and nutrition. Outer membrane vesicles can diffuse across long distances in environments with abundant water.
• Bacterial physiology: Something in the air | PDF (179 KB)
  - Nat Rev Microbiol 9(8):562 (2011)
  Bacteria produce many volatile compounds, but little is known about their biological functions. Now, Ghigo and colleagues report that gaseous ammonia produced by bacteria increases the intracellular level of polyamines and modulates antibiotic resistance and oxidative stress responses in physically separated bacteria.
• Genome watch: Honey, I shrunk the mimiviral genome | PDF (142 KB)
  - Nat Rev Microbiol 9(8):563 (2011)
  This month's Genome Watch describes how the large size of the mimiviral genome is a result of the sympatric lifestyle of mimivirus in host amoebae.
• In the news | PDF (256 KB)
  - Nat Rev Microbiol 9(8):564 (2011)
  Going to the beach may be less healthy than we thought, according to a new report by the US Natural Resources Defense Council. The number of beach closures and warnings due to high bacterial contamination in the United States in 2010 was the second highest since records began 21 years ago.
• Disease watch In the news
  - Nat Rev Microbiol 9(8):564 (2011)
  In this Disease Watch, our statement that the strain responsible for the enterohaemorrhagic Escherichia coli (EHEC) outbreak "is a rare strain that has never before been found in humans" was incorrect. It was initially reported that strain responsible, O104:H4, had previously not been thought to be responsible for an outbreak; however, it is now known that the strain responsible for the outbreak is closely related to strains that have caused infections in humans. The text now reads: "The strain of E. coli that caused the outbreak, O104:H4, has now been sequenced; sequence analysis suggests that horizontal gene transfer may have combined virulence factors from several strains, producing a particularly virulent bacterium." We apologize for any confusion caused.
• Temporal and spatial oscillations in bacteria
  - Nat Rev Microbiol 9(8):565 (2011)
  Oscillations pervade biological systems at all scales. In bacteria, oscillations control fundamental processes, including gene expression, cell cycle progression, cell division, DNA segregation and cell polarity. Oscillations are generated by biochemical oscillators that incorporate the periodic variation in a parameter over time to generate an oscillatory output. Temporal oscillators incorporate the periodic accumulation or activity of a protein to drive temporal cycles such as the cell and circadian cycles. Spatial oscillators incorporate the periodic variation in the localization of a protein to define subcellular positions such as the site of cell division and the localization of DNA. In this Review, we focus on the mechanisms of oscillators and discuss the design principles of temporal and spatial oscillatory systems.
• Hfq and its constellation of RNA
  - Nat Rev Microbiol 9(8):578 (2011)
  Hfq is an RNA-binding protein that is common to diverse bacterial lineages and has key roles in the control of gene expression. By facilitating the pairing of small RNAs with their target mRNAs, Hfq affects the translation and turnover rates of specific transcripts and contributes to complex post-transcriptional networks. These functions of Hfq can be attributed to its ring-like oligomeric architecture, which presents two non-equivalent binding surfaces that are capable of multiple interactions with RNA molecules. Distant homologues of Hfq occur in archaea and eukaryotes, reflecting an ancient origin for the protein family and hinting at shared functions. In this Review, we describe the salient structural and functional features of Hfq and discuss possible mechanisms by which this protein can promote RNA interactions to catalyse specific and rapid regulatory responses in vivo.
• Influenza A viruses: new research developments
  - Nat Rev Microbiol 9(8):590 (2011)
  Influenza A viruses are zoonotic pathogens that continuously circulate and change in several animal hosts, including birds, pigs, horses and humans. The emergence of novel virus strains that are capable of causing human epidemics or pandemics is a serious possibility. Here, we discuss the value of surveillance and characterization of naturally occurring influenza viruses, and review the impact that new developments in the laboratory have had on our understanding of the host tropism and virulence of viruses. We also revise the lessons that have been learnt from the pandemic viruses of the past 100 years.
• Leishmaniasis: complexity at the host–pathogen interface
  - Nat Rev Microbiol 9(8):604 (2011)
  Leishmania is a genus of protozoan parasites that are transmitted by the bite of phlebotomine sandflies and give rise to a range of diseases (collectively known as leishmaniases) that affect over 150 million people worldwide. Cellular immune mechanisms have a major role in the control of infections with all Leishmania spp. However, as discussed in this Review, recent evidence suggests that each host–pathogen combination evokes different solutions to the problems of parasite establishment, survival and persistence. Understanding the extent of this diversity will be increasingly important in ensuring the development of broadly applicable vaccines, drugs and immunotherapeutic interventions.
• Why do RNA viruses recombine?
  - Nat Rev Microbiol 9(8):617 (2011)
  Recombination occurs in many RNA viruses and can be of major evolutionary significance. However, rates of recombination vary dramatically among RNA viruses, which can range from clonal to highly recombinogenic. Here, we review the factors that might explain this variation in recombination frequency and show that there is little evidence that recombination is favoured by natural selection to create advantageous genotypes or purge deleterious mutations, as predicted if recombination functions as a form of sexual reproduction. Rather, recombination rates seemingly reflect larger-scale patterns of viral genome organization, such that recombination may be a mechanistic by-product of the evolutionary pressures acting on other aspects of virus biology.
• The skin microbiome
  - Nat Rev Microbiol 9(8):626 (2011)
  It has been brought to our attention that in Fig. 1 of the original article the morphology and localization of the Demodex mites were not accurate. We have corrected the figure to show a cartoon that is more representative of the straight body and short limbs of these mites, and of their localization in the hair follicle. The correct figure is shown below. We thank I. Dekio for bringing this to our attention and apologize to readers for any confusion caused.