Plastic Debris As a Vector for Bacterial Disease: An Interdisciplinary Systematic Review.

Pathogens and polymers can separately cause disease; however, environmental and medical researchers are increasingly investigating the capacity of polymers to transfer pathogenic bacteria, and cause disease, to hosts in new environments. We integrated causal frameworks from ecology and epidemiology into one interdisciplinary framework with four stages (colonization, survival, transfer, disease). We then systematically and critically reviewed 111 environmental and medical papers. We show 58% of studies investigated the colonization-stage alone but used this as evidence to classify a substratum as a vector. Only 11% of studies identified potential pathogens, with only 3% of studies confirming the presence of virulence-genes. Further, 8% of studies investigated µm-sized polymers with most (58%) examining less pervasive cm-sized polymers. No study showed bacteria can preferentially colonize, survive, transfer, and cause more disease on polymers compared to other environmental media. One laboratory experiment demonstrated plausibility for polymers to be colonized by a potential pathogen (Escherichia coli), survive, transfer, and cause disease in coral (Astrangia poculata). Our analysis shows a need for linked structured surveys with environmentally relevant experiments to understand patterns and processes across the vectoral stages, so that the risks and impacts of pathogens on polymers can be assessed with more certainty.

Archaea join the conversation: detection of AHL-like activity across a range of archaeal isolates.

Quorum sensing is a mechanism of genetic control allowing single cell organisms to coordinate phenotypic response(s) across a local population and is often critical for ecosystem function. Although quorum sensing has been extensively studied in bacteria comparatively less is known about this mechanism in Archaea. Given the growing significance of Archaea in both natural and anthropogenic settings, it is important to delineate how widespread this phenomenon of signaling is in this domain. Employing a plasmid-based AHL biosensor in conjunction with thin-layer chromatography (TLC), the present study screened a broad range of euryarchaeota isolates for potential signaling activity. Data indicated the presence of 11 new Archaeal isolates with AHL-like activity against the LuxR-based AHL biosensor, including for the first time putative AHL activity in a thermophile. The presence of multiple signals and distinct changes between growth phases were also shown via TLC. Multiple signal molecules were detected using TLC in Haloferax mucosum, Halorubrum kocurii, Natronococcus occultus and Halobacterium salinarium. The finding of multiple novel signal producers suggests the potential for quorum sensing to play an important role not only in the regulation of complex phenotypes within Archaea but the potential for cross-talk with bacterial systems.

A global growth-form database for 143,616 vascular plant species.

For the majority of plant species in the world, we know little about their functional ecology, and not even one of the most basic traits-the species' growth habit. To fill the gap in availability of compiled plant growth-form data, we have assembled what is, to our knowledge, the largest global database on growth-form as a plant trait. We have, with extensive error checking and data synthesis, assembled a growth-form database from 163 data sources for 143,616 vascular plant species from 445 different plant families. This is 38.6% of the currently accepted vascular plant diversity. For our database, we have chosen seven categories to cover the majority of the diversity in plant growth forms: aquatic plants, epiphytes, hemiepiphytes, climbing plants, parasitic plants, holo-mycoheterotrophs, and freestanding plants. These categories were used because we were able to reconcile the wealth of existing definitions and types of growth-form information available globally to them clearly and unequivocally, and because they are complementary with existing databases. Plants in the database were designated into a category if their adult growth form fit the criterion. We make available two databases: first, the complete data set, including species for which there is currently conflicting information, and second, a consensus data set, where all available information supports one categorization. Of the plant species for which we found information, 103,138 (72%) are freestanding, 21,110 (15%) are epiphytes, and 4,046 (3%) are parasites. Our growth-form data can be used to produce useful summary statistics by clade. For example, current data suggests that half of pteridophytes are epiphytic, that all hemiepiphytes are eudicots, and that there are no parasitic monocots, gymnosperms, or pteridophytes. Growth form is a crucial piece of fundamental plant-trait data with implications for each species' ecology, evolution, and conservation, and thus this data set will be useful for a range of basic and applied questions across these areas of research. No copyright or proprietary restrictions are associated with the use of this data set, other than citation of the present Data Paper. A static version of this dataset is provided as Supporting Information, and a living and updating version of the dataset is available in a GitHub repository.