WIKIMEDIA COMMONS, CDC (PHIL #1187)
1. I Spy Researchers testing the ability of engineered E. coli cells to stabilize unstable proteins in vivo, stumbled upon a new protein chaperone called Spy that suppresses protein aggregation and aids protein refolding. Spy is shaped unlike any other previously studied chaperone and can increase the steady-state levels of a set of unstable protein mutants up to 700-fold.
Researchers found a new way by which the intracellular bacterium Legionella pneumophila, responsible for Legionnaires' disease, modifies the proteins of the cells it infects in order to alter membrane transport and ensure its own replication.
A commensal bacterial strain that processes milk reduces anxiety and depression-like behaviors in mice, and alters expression of receptors for the neurotransmitter GABA—associated with modulating psychological processes—in several areas of the brain. The research suggests that the bacteria, also found in the human gut, may have similar effects in people.
J.A. Bravo et al., "Ingestion of Lactobacillus strain regulates emotional behavior and central GABA receptor expression in a mouse via the vagus nerve," PNAS, 108:16050-55, 2011. Free F1000 Evaluation
Inflammasomes activate innate immune inflammation, but how these proteins were activated was poorly understood. Now researchers discovered a family of proteins called NAIPs, previously thought to play a non-essential role, act as sensors that specifically detect several bacterial components and activate the inflammasome.
Many companies are trying to overcome malaria-drug resistance by targeting the malaria parasite's plant-derived organelle, known to be essential for its survival, but the organelle's actual function was unknown. Now researchers showed that it produces isopentyle pyrophosphate (IPP), a precursor to a number of molecules vital for the parasite's survival during the blood phase. The study could have major implications for the development of anti-malarial drugs.
6. HIV evades NK death Just as T cells provide pressure on HIV to adapt and escape recognition, it now appears NK cells also can drive HIV evolution. Researchers identified polymorphisms in strains of HIV-1 that prevented activation of NK cells with specific killer immunoglobulin-like receptors (KIRs).
7. Molecular fountain of youth? Replicating cells of complex organisms can reset the cellular clock of progeny, essentially resetting their age. Researchers identify a transcription factor called NDT80, which is essential for gametogenesis in budding yeast, allowing yeast cells to extend the number of times they replicate. Transient expression of NDT80 in yeast cells that weren’t undergoing gametogenesis could also reset their life span.
The F1000 Top 7 is a snapshot of the highest ranked articles from a 14-day period on Faculty of 1000 Microbiology, as calculated on September 22, 2011. Faculty Members evaluate and rate the most important papers in their field. To see the latest rankings, search the database, and read daily evaluations, visit http://f1000.com.