The means by which vaginal microbiomes help prevent urogenital diseases in women and maintain health are poorly understood. To gain insight into this, the vaginal bacterial communities of 396 asymptomatic North American women who represented four ethnic groups (white, black, Hispanic, and Asian) were sampled and the species composition characterized by pyrosequencing of barcoded 16S rRNA genes. The communities clustered into five groups: four were dominated by Lactobacillus iners, L. crispatus, L. gasseri, or L. jensenii, whereas the fifth had lower proportions of lactic acid bacteria and higher proportions of strictly anaerobic organisms, indicating that a potential key ecological function, the production of lactic acid, seems to be conserved in all communities. The proportions of each community group varied among the four ethnic groups, and these differences were statistically significant [χ 2 (10) = 36.8, P < 0.0001]. Moreover, the vaginal pH of women in different ethnic groups also differed and was higher in Hispanic (pH 5.0 ± 0.59) and black (pH 4.7 ± 1.04) women as compared with Asian (pH 4.4 ± 0.59) and white (pH 4.2 ± 0.3) women. Phylotypes with correlated relative abundances were found in all communities, and these patterns were associated with either high or low Nugent scores, which are used as a factor for the diagnosis of bacterial vaginosis. The inherent differences within and between women in different ethnic groups strongly argues for a more refined definition of the kinds of bacterial communities normally found in healthy women and the need to appreciate differences between individuals so they can be taken into account in risk assessment and disease diagnosis. T he human body harbors microorganisms that inhabit surfaces and cavities exposed or connected to the external environment. Each body site includes ecological communities of microbial species that exist in a mutualistic relationship with the host. The kinds of organisms present are highly dependent on the prevailing environmental conditions and host factors and hence vary from site to site. Moreover, they vary between individuals and over time (1). The human vaginal microbiota seem to play a key role in preventing a number of urogenital diseases, such as bacterial vaginosis, yeast infections, sexually transmitted infections, urinary tract infections (2-9), and HIV infection (10, 11). Common wisdom attributes this to lactic acid-producing bacteria, mainly Lactobacillus sp., that commonly inhabit the vagina. These species are thought to play key protective roles by lowering the environmental pH through lactic acid production (12, 13), by producing various bacteriostatic and bacteriocidal compounds, or through competitive exclusion (13-16). The advent of culture-independent molecular approaches based on the cloning and sequencing of 16S rRNA genes has furthered our understanding of the vaginal microbiota by identifying taxa that had not been cultured (17-24). However, this technique is limited by high cost and low throughput, hence only small ...

SignificanceDecades of research have fostered the now-prevalent assumption that noncrop habitat facilitates better pest suppression by providing shelter and food resources to the predators and parasitoids of crop pests. Based on our analysis of the largest pest-control database of its kind, noncrop habitat surrounding farm fields does affect multiple dimensions of pest control, but the actual responses of pests and enemies are highly variable across geographies and cropping systems. Because noncrop habitat often does not enhance biological control, more information about local farming contexts is needed before habitat conservation can be recommended as a viable pest-suppression strategy. Consequently, when pest control does not benefit from noncrop vegetation, farms will need to be carefully comanaged for competing conservation and production objectives.

Managing agricultural landscapes to support biodiversity and ecosystem services is a key aim of a sustainable agriculture. However, how the spatial arrangement of crop fields and other habitats in landscapes impacts arthropods and their functions is poorly known. Synthesising data from 49 studies (1515 landscapes) across Europe, we examined effects of landscape composition (% habitats) and configuration (edge density) on arthropods in fields and their margins, pest control, pollination and yields. Configuration effects interacted with the proportions of crop and non-crop habitats, and species' dietary, dispersal and overwintering traits led to contrasting responses to landscape variables. Overall, however, in landscapes with high edge density, 70% of pollinator and 44% of natural enemy species reached highest abundances and pollination and pest control improved 1.7-and 1.4-fold respectively. Arable-dominated landscapes with high edge densities achieved high yields. This suggests that enhancing edge density in European agroecosystems can promote functional biodiversity and yield-enhancing ecosystem services.

To our knowledge, no data are available on whether the microbial species composition and abundance sampled with self-collected vaginal swabs are comparable to those of swabs collected by clinicians. Twenty healthy women were recruited to the study during a routine gynecological visit. Eligible women were between 18 and 40 years old with regular menstrual cycles. Participants self-collected a vaginal swab using a standardized protocol and then were examined by a physician, who collected an additional five swabs from the lateral wall of the mid-vagina. In this study, the self-collected and three physician-obtained swabs were analyzed and compared using terminal restriction fragment length polymorphism and sequence analyses of the 16S rRNA genes. Vaginal microbial community comparative statistical analyses of both T-RFLP and 16S rRNA gene sequence datasets revealed that self-collected vaginal swabs sampled the same microbial diversity as physician collected swabs of the mid-vagina. These findings enable large-scale, field-based studies of the vaginal microbiome.In recent years, "cultivation-independent" methods based on the analysis of 16S rRNA gene sequences directly extracted from biological samples are widely used to explore microbial diversity in various habitats (7,27,28). Using these methods, organisms are classified based on phylogenetic differences that are reflected in sequence polymorphisms of their 16S rRNA genes. The use of these approaches obviates the need to cultivate organisms, permits high-throughput analysis of samples, and provides precise and detailed information about the populations present. Using 16S rRNA gene analysis, the species (phylotype) composition and abundance in microbial communities can be readily determined, and similarities and differences among microbial communities can be quantitatively discerned. Despite difficulties in comparing data generated by different so-called "universal" PCR primer pairs, each introducing small biases (8, 36), this validated method has become the favored approach to characterizing the mutualistic microbial populations residing on and in the human body, including the gastrointestinal tract (4, 37), skin (4, 10), subgingival crevice (19), and vagina (4, 9, 15, 42). Importantly, the data obtained can be statistically analyzed to test the significance of changes that occur within individuals over time, or between individuals and treatment groups. These methods include terminal restriction fragment length polymorphisms (T-RFLP) (41) and high-throughput pyrosequencing of bar-coded 16S rRNA gene analysis (12,22).Surveys of vaginal microbial communities using cultivationindependent methods have been initiated under the NIH Roadmap Human Microbiome Project (14). Surveys of the vagina are important for a number of reasons. The beneficial effects of the endogenous microbiota on women's health in obstetric and gynecologic outcomes are numerous but poorly understood. A proper understanding of community membership, relative abundance, and variations therein are crit...

Succession is defined as changes in biological communities over time. It has been extensively studied in plant communities, but little is known about bacterial succession, in particular in environments such as High Arctic glacier forelands. Bacteria carry out key processes in the development of soil, biogeochemical cycling, and facilitating plant colonization. In this study we sampled two roughly parallel chronosequences in the foreland of Midre Lovén glacier on Svalbard, Norway and tested whether any of several factors were associated with changes in the structure of bacterial communities, including time after glacier retreat, horizontal variation caused by the distance between chronosequences, and vertical variation at two soil depths. The structures of soil bacterial communities at different locations were compared using terminal restriction fragment length polymorphisms (T-RFLP) of 16S rRNA genes, and the data were analyzed by sequential analysis of log-linear statistical models. While no significant differences in community structure were detected between the two chronosequences, statistically significant differences between sampling locations in the surface and mineral soils could be demonstrated even though glacier forelands are patchy and dynamic environments. These findings suggest bacterial succession occurs in High Arctic glacier forelands but may differ in different soil depths.