CotG controls spore surface formation in response to the temperature of growth in Bacillus subtilis

Bacterial spores of the Bacillus genus are ubiquitous in nature and are commonly isolated from a variety of diverse environments. Such wide distribution mainly reflects the spore resistance properties but some Bacillus species can grow/sporulate in at least some of the environments where they have been originally isolated. Growing and sporulating at different conditions is known to affect the structure and the resistance properties of the produced spore. In B. subtilis the temperature of growth and sporulation has been shown to influence the structure of the spore surface throughout the action of a sporulation-specific and heat-labile kinase CotH. Here we report that CotG, an abundant component of the B. subtilis spore surface and a substrate of the CotH kinase, assembles around the forming spore but also accumulates in the mother cell cytoplasm where it forms aggregates with at least two other coat components. Our data suggest that the thermo-regulator CotH contributes to the switch between the coat of 25°C and that of 42°C spores by controlling the phosphorylation levels of CotG that, in turn, regulates the assembly of at least two other coat components.     

Intelligent Decision-Making Models for Disaster Management

ABSTRACT

Providing emergency relief to the victims of natural disasters is a hugely complex process fraught with many challenging aspects: multiple uncertainties, little reliable information, scarcity of resources, a variety of involved entities, and so on. Nowadays there is a lot of information that could be used to improve decision-making in disaster management, but usually it is not available at the right moment, in the right way, or it is partially known or vague. In this article we analyze the decision-making process for disaster management from the general view of intelligent decision-making to the specific characteristics of this context. This specificity deals with a new kind of logistics, and it is shown how this humanitarian logistics, specifically designed with the aim of alleviating suffering of vulnerable people, is a growing new research area to develop new decision aid models for disaster management, identifying new and relevant differences with other types of logistics. To illustrate these claims, two models are introduced, one for assessment of consequences in the earlier stage after a disaster (focused on the unknown, one of the main characteristics in disaster management), and another one for last mile distribution of humanitarian aid (focused on the multicriteria nature of decision-making on disaster management).     

Thematic Review Series: Bile Acids: Bile acids as regulatory molecules

In the past, bile acids were considered to be just detergent molecules derived from cholesterol in the liver. They were known to be important for the solubilization of cholesterol in the gallbladder and for stimulating the absorption of cholesterol, fat-soluble vitamins, and lipids from the intestines. However, during the last two decades, it has been discovered that bile acids are regulatory molecules. Bile acids have been discovered to activate specific nuclear receptors (farnesoid X receptor, preganane X receptor, and vitamin D receptor), G protein coupled receptor TGR5 (TGR5), and cell signaling pathways (c-jun N-terminal kinase 1/2, AKT, and ERK 1/2) in cells in the liver and gastrointestinal tract. Activation of nuclear receptors and cell signaling pathways alter the expression of numerous genes encoding enzyme/proteins involved in the regulation of bile acid, glucose, fatty acid, lipoprotein synthesis, metabolism, transport, and energy metabolism. They also play a role in the regulation of serum triglyceride levels in humans and rodents. Bile acids appear to function as nutrient signaling molecules primarily during the feed/fast cycle as there is a flux of these molecules returning from the intestines to the liver following a meal. In this review, we will summarize the current knowledge of how bile acids regulate hepatic lipid and glucose metabolism through the activation of specific nuclear receptors and cell signaling pathways.     

Biodiversity and distribution of epibiontic communities on Caridina ensifera (Crustacea,Decapoda, Atyidae) from Lake Poso: comparison with another ancient lake system of Sulawesi (Indonesia)

Fernandez‐Leborans, G. and von Rintelen, K. 2010. Biodiversity and distribution of epibiontic communities on Caridina ensifera (Crustacea, Decapoda, Atyidae) from Lake Poso: comparison with another ancient lake system of Sulawesi (Indonesia). — Acta Zoologica (Stockholm) 91 : 163–175 The epibiont communities of the shrimp Caridina ensifera, endemic to Lake Poso (Sulawesi, Indonesia), were analysed. Most of the epibiont species were ciliated protozoa belonging to three suctorian genera (Acineta, Podophrya and Spelaeophrya), three peritrich genera (Zoothamnium, Vorticella and Cothurnia), and a haptorid genus (Amphileptus). There was also a rotifer epibiont of the genus Embata. Epibionts were identified to species level. There were 14 to 1114 epibionts per shrimp. The distribution of the epibiont species on the surface of the basibiont was recorded, calculating the number on the different colonized individuals of C. ensifera. The most abundant species, Zoothamnium intermedium and Acineta sulawesiensis, were also the most widely distributed. There was a significant difference between the spatial distributions of the different epibiont species. The analysis of the number of the epibiont species throughout the anteroposterior axis of the shrimp showed a gradient from the anterior to the posterior end of the body. Data from Lake Poso were compared with those of the Malili lake system (Sulawesi), obtained from its endemic shrimp, Caridina lanceolata. Lake Poso had the highest mean diversity, while Lake Mahalona showed the highest maximum diversity. All lakes were correlated with respect to the mean number of epibionts on the anatomical units of the shrimp, which showed a similar general distribution. The distributions of the different epibiont species were compared between the lakes. The possible adaptations of the epibionts as well as the colonization patterns were discussed. From the statistical results and the analysis of the distributions, we propose that in these communities epibiont species have a pattern of colonization in which they follow a behaviour as a whole; each species has a differential distribution, with the species occupying the available substratum with the particular requirements of each functional group, but there is a trend towards maintaining an equilibrium among species and groups, compensating for diversity and number of individuals. In all lakes there was an epibiont distribution model comprising the maintenance of an anteroposterior axis gradient, which was supported by the fluctuation in diversity and number of individuals of the different functional groups of epibiont species. The functional role of the different groups of species seems to tend towards sustainability with little global variation among the lakes.     

Evolutionary history and molecular epidemiology of rabbit haemorrhagic disease virus in the Iberian Peninsula and Western Europe

Background  

Rabbit haemorrhagic disease virus (RHDV) is a highly virulent calicivirus, first described in domestic rabbits in China in 1984. RHDV appears to be a mutant form of a benign virus that existed in Europe long before the first outbreak. In the Iberian Peninsula, the first epidemic in 1988 severely reduced the populations of autochthonous European wild rabbit. To examine the evolutionary history of RHDV in the Iberian Peninsula, we collected virus samples from wild rabbits and sequenced a fragment of the capsid protein gene VP60. These data together with available sequences from other Western European countries, were analyzed following Bayesian Markov chain Monte Carlo methods to infer their phylogenetic relationships, evolutionary rates and demographic history.