MicrobiologyOpen Publishes Issue 2:1
February 21, 2013
The latest issue of MicrobiologyOpen is available online now! 16 new articles are fully open access: free to read, download and share.
Below are some top articles highlighted by the Editor-in-Chief, Pierre Cornelis:
First insights into the syntrophic acetate-oxidizing bacteria – a genetic study Bettina Müller, Li Sun and Anna Schnürer
Summary: In this article we provide the first genetic characterization of syntrophic acetate-oxidizing bacteria (SAOB) being able to make a living close to the thermodynamic equilibrium. To understand the fundamental biochemical and regulatory mechanisms behind syntrophic acetate oxidation, we identified the respective formyltetrahydrofolate synthetase gene (fhs), encoding a key enzyme of the Wood–Ljungdahl pathway used by these organisms under heterotrophic and syntrophic growth conditions. We further investigated fhs mRNA expression and analyzed the surrounding gene structures.
Sa-Lrp from Sulfolobus acidocaldarius is a versatile, glutamine-responsive, and architectural transcriptional regulator Amelia Vassart, Marleen Van Wolferen, Alvaro Orell, Ye Hong, Eveline Peeters, Sonja-Verena Albers and Daniel Charlier
Summary: The Lrp-like regulator Sa-Lrp binds in a glutamine-dependent manner to AT-rich binding sites and induces bending and wrapping upon binding. Furthermore, by analyzing an Sa-lrp deletion mutant, we demonstrate that the protein affects transcription of some of the genes of which the promoter region is targeted and that it is an important determinant of the cellular aggregation phenotype. Therefore, Sa-Lrp is a glutamine-responsive global transcriptional regulator with an additional architectural role.
Cell-free production of integral membrane aspartic acid proteases reveals zinc-dependent methyltransferase activity of the Pseudomonas aeruginosa prepilin peptidase PilD Khaled A. Aly, Emily T. Beebe, Chi H. Chan, Michael A. Goren, Carolina Sepúlveda, Shin-ichi Makino, Brian G. Fox and Katrina T. Forest
Summary: The integral membrane aspartic acid protease PilD was synthesized in a cell-free translation system, as was its full-length substrate, PilA. The purified enzyme displayed both of its known biochemical activities: cleavage of the PilA signal peptide and S-adenosyl methionine-dependent methylation of the mature PilA. We show that PilD is a zinc binding protein, and zinc is required for the methylation activity but not the peptidase activity of PilD.
Evidence that a transcription factor regulatory network coordinates oxidative stress response and secondary metabolism in aspergilli Sung-Yong Hong, Ludmila V. Roze, Josephine Wee and John E. Linz
Summary: The data strongly suggest that at least four transcription factors (AtfB,SrrA,AP-1, and MsnA) participate in the regulatory network that induces aflatoxin biosynthesis as part of the cellular response to oxidative stress in Aspergillus parasiticus.