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Streptomyces species produce many important antibiotics and have a crucial role in soil nutrient cycling. However, their evolutionary history remains poorly characterized. We have evaluated the impact of homologous recombination on the evolution of Streptomyces using multi-locus sequence analysis of 234 strains that represent at least 11 species clusters. Evidence of inter-species recombination is widespread but not uniform within the genus and levels of mosaicism vary between species clusters. Most phylogenetically incongruent loci are monophyletic at the scale of species clusters and their subclades, suggesting that these recombination events occurred in shared ancestral lineages. Further investigation of two mosaic species clusters suggests that genes acquired by inter-species recombination may have become fixed in these lineages during periods of demographic expansion; implicating a role for phylogeography in determining contemporary patterns of genetic diversity. Only by examining the phylogeny at the scale of the genus is apparent that widespread phylogenetically incongruent loci in Streptomyces are derived from a far smaller number of ancestral inter-species recombination events.

Biological soil crusts (BSCs) are key components of ecosystem productivity in arid lands and they cover a substantial fraction of the terrestrial surface. In particular, BSC N2-fixation contributes significantly to the nitrogen (N) budget of arid land ecosystems. In mature crusts, N2-fixation is largely attributed to heterocystous cyanobacteria; however, early successional crusts possess few N2-fixing cyanobacteria and this suggests that microorganisms other than cyanobacteria mediate N2-fixation during the critical early stages of BSC development. DNA stable isotope probing with 15N2revealed that Clostridiaceae and Proteobacteria are the most common microorganisms that assimilate 15N2in early successional crusts. The Clostridiaceae identified are divergent from previously characterized isolates, though N2-fixation has previously been observed in this family. The Proteobacteria identified share >98.5% small subunit rRNA gene sequence identity with isolates from genera known to possess diazotrophs (for example, Pseudomonas, Klebsiella, Shigella and Ideonella). The low abundance of these heterotrophic diazotrophs in BSCs may explain why they have not been characterized previously. Diazotrophs have a critical role in BSC formation and characterization of these organisms represents a crucial step towards understanding how anthropogenic change will affect the formation and ecological function of BSCs in arid ecosystems.

ABSTRACTBats of the genus Myotiscannot be identified reliably using conventional acoustic analyses. Here we use morphology of echolocation calls to discriminate between Myotisspp. This method may be used to identify unknown roosts to species level. Echolocation calls of M. daubentonii, M. mystacinusand M. nattereri, were recorded in emergence flights from roosts. Images of echolocation calls were extracted for morphological analysis performed in SHAPE, a program that transforms two-dimensional outline data into Elliptic Fourier Descriptors. Species typical call shapes were described with Mahalanobis models. Discriminant Function Analyses (DFA) were applied with Mahalanobis scores of typical shape alone and with a spectral call parameter, maximum frequency. DFA achieved an overall correct classification rate of 88.9% using typical outline shapes alone. Correct classification of 100% of both M. daubentoniiand M. mystacinuswas achieved by both typical call outlines. For M. nattereri, 79.6% of calls were correctly classified by call morphology, but the addition of maximum frequency improved this to 96.3%. Shape analyses provide a quick and easy method of distinguishing Myotisspecies under field conditions and could be extended to include other species of bats that share conventional acoustic parameters.

The article focuses on kickstarting a fitness comeback in the New Year, offering strategies for long-term success. Topics include creating a workout plan and making healthier food choices, familiarizing oneself with the gym and scheduling workouts, and emphasizing long-term habits for year-round fitness.

The Verrucomicrobia constitute a newly discovered division of the Bacteria identified as a numerically abundant component of soil microbial communities in numerous sites around the world. The relative abundance of rRNA from Verrucomicrobia was investigated in the soil to examine the influence of specific environmental factors on the distribution of Verrucomicrobia and to better understand the distribution of this group in terrestrial ecosystems. The abundance of the verrucomicrobial rRNA was determined by using a novel oligonucleotide probe that is specific for verrucomicrobial 16S rRNA. The abundance of verrucomicrobial 16S rRNA in soil microbial communities was determined in relation to plant community composition and soil management history over a period of 2 years. Additional samples were analyzed to determine if verrucomicrobial rRNA relative abundance changes in relation to either soil depth or soil moisture content. The Verrucomicrobia composed 1.9±0.2% of the microbial community rRNA present in the 85 soil samples examined. The distribution of verrucomicrobial rRNA in the soil reveals that Verrucomicrobia are significantly affected by environmental characteristics that change in relation to time, soil history, and soil depth, and reveals that a statistically significant amount of the variation in verrucomicrobial rRNA abundance can be explained by changes in soil moisture content.

The article features Navajo/Ute flutist R. Carlos Nakai. He is one of the most prominent figures in Native American music. He is the first traditional flutist to earn a gold record for certified sales of over 500,00 copies for 1989's music release "Canyon Trilogy." He has also received several awards and recognitions in the music industry. Information is given on how he started his career as a flutist. He has developed the philosophy of not trying to change the instrument but rather to work with it and learn how to include it in other disciplines.

Our study reveals the ecogenomic traits of microorganisms participating in the cellulose economy of soil. We identified three major categories of participants in this economy: (i) independent primary degraders, (ii) interdependent primary degraders, and (iii) secondary consumers (mutualists, opportunists, and parasites).

Aflatoxin, produced by the fungus Aspergillus flavus, is an extremely potent hepatotoxin that causes acute toxicosis and cancer, and it incurs hundreds of millions of dollars annually in agricultural losses. Despite the importance of this toxin to humans, it has remained unclear what the fungus gains by producing aflatoxin. In fact, not all strains of A. flavusproduce aflatoxin. Previous work has shown an advantage to producing aflatoxin in the presence of some insects. Our current work demonstrates the first evidence of a disadvantage to A. flavusin producing aflatoxin when competing with soil microbes. Together, these opposing evolutionary forces could explain the persistence of both aflatoxigenic and nonaflatoxigenic strains through evolutionary time.

Phosphoinositide-3-kinase d (PI3Kd) is a critical regulator of cell growth and transformation and has been explored as a therapeutic target for a range of diseases. Through the exploration of the thienopyrimidine scaffold, we have identified a ligand-efficient methylation that leads to remarkable selectivity for PI3Kd over the closely related isoforms. Interrogation through the Free–Wilson analysis highlights the innate selectivity the thienopyrimidine scaffold has for PI3Kd and provides a predictive model for the activity against the PI3K isoforms.

ABSTRACTWe show that Streptomycesbiogeography in soils across North America is influenced by the regional diversification of microorganisms due to dispersal limitation and genetic drift. Streptomycesspp. form desiccation-resistant spores, which can be dispersed on the wind, allowing for a strong test of whether dispersal limitation governs patterns of terrestrial microbial diversity. We employed an approach that has high sensitivity for determining the effects of genetic drift. Specifically, we examined the genetic diversity and phylogeography of physiologically similar Streptomycesstrains isolated from geographically distributed yet ecologically similar habitats. We found that Streptomycesbeta diversity scales with geographic distance and both beta diversity and phylogenetic diversity manifest in a latitudinal diversity gradient. This pattern of Streptomycesbiogeography resembles patterns seen for diverse species of plants and animals, and we therefore evaluated these data in the context of ecological and evolutionary hypotheses proposed to explain latitudinal diversity gradients. The data are consistent with the hypothesis that niche conservatism limits dispersal, and historical patterns of glaciation have limited the time for speciation in higher-latitude sites. Most notably, higher-latitude sites have lower phylogenetic diversity, higher phylogenetic clustering, and evidence of range expansion from lower latitudes. In addition, patterns of beta diversity partition with respect to the glacial history of sites. Hence, the data support the hypothesis that extant patterns of Streptomycesbiogeography have been driven by historical patterns of glaciation and are the result of demographic range expansion, dispersal limitation, and regional diversification due to drift.IMPORTANCEBiogeographic patterns provide insight into the evolutionary and ecological processes that govern biodiversity. However, the evolutionary and ecological processes that govern terrestrial microbial diversity remain poorly characterized. We evaluated the biogeography of the genus Streptomycesto show that the diversity of terrestrial bacteria is governed by many of the same processes that govern the diversity of many plant and animal species. While bacteria of the genus Streptomycesare a preeminent source of antibiotics, their evolutionary history, biogeography, and biodiversity remain poorly characterized. The observations we describe provide insight into the drivers of Streptomycesbiodiversity and the processes that underlie microbial diversification in terrestrial habitats.

Using the foraging movements of an insectivorous bat, Myotis mystacinus, we describe temporal switching of foraging behaviour in response to resource availability. These observations conform to predictions of optimized search under the Lévy flight paradigm. However, we suggest that this occurs as a result of a preference behaviour and knowledge of resource distribution. Preferential behaviour and knowledge of a familiar area generate distinct movement patterns as resource availability changes on short temporal scales. The behavioural response of predators to changes in prey fields can elicit different functional responses, which are considered to be central in the development of stable predator–prey communities. Recognizing how the foraging movements of an animal relate to environmental conditions also elucidates the evolution of optimized search and the prevalence of discrete strategies in natural systems. Applying techniques that use changes in the frequency distribution of movements facilitates exploration of the processes that underpin behavioural changes.

Fluoride at concentrations greater than 0.01 mM was found to be a quasi-irreversible inhibitor of enolase of permeabilized cells of Streptococcus mutans GS-5 and also of isolated yeast enolase. The inhibition appeared to be of the type that has been described for P-ATPases, but was not dependent on added Al3+ or Be2+ ions. Fluoride inhibition of enolase was not reversed by repeatedly washing the permeabilized cells in chilled fluoride-free medium but could be reversed by the product, phosphoenolpyruvate, or by very high levels of the substrate, 2-phosphoglycerate. Irreversible inhibition of glycolysis was not evident after fluoride treatment of intact cells, washing to remove unbound or loosely bound fluoride and addition of glucose, presumably because intracellular levels of phosphoenolpyruvate were sufficiently high to preclude irreversible fluoride inhibition of enolase.