Non-redundant metagenome-assembled genomes of activated sludge reactors at different disturbances and scales.

Metagenome-assembled genomes (MAGs) are microbial genomes reconstructed from metagenomic data and can be assigned to known taxa or lead to uncovering novel ones. MAGs can provide insights into how microbes interact with the environment. Here, we performed genome-resolved metagenomics on sequencing data from four studies using sequencing batch reactors at microcosm (~25 mL) and mesocosm (~4 L) scales inoculated with sludge from full-scale wastewater treatment plants. These studies investigated how microbial communities in such plants respond to two environmental disturbances: the presence of toxic 3-chloroaniline and changes in organic loading rate. We report 839 non-redundant MAGs with at least 50% completeness and 10% contamination (MIMAG medium-quality criteria). From these, 399 are of putative high-quality, while sixty-seven meet the MIMAG high-quality criteria. MAGs in this catalogue represent the microbial communities in sixty-eight laboratory-scale reactors used for the disturbance experiments, and in the full-scale wastewater treatment plant which provided the source sludge. This dataset can aid meta-studies aimed at understanding the responses of microbial communities to disturbances, particularly as ecosystems confront rapid environmental changes.

Balancing public health and group privacy: Ethics, rights, and obligations for wastewater surveillance systems.

As the threat of COVID-19 recedes, wastewater surveillance - unlike other pandemic-era public health surveillance methods - seems here to stay. Concerns have been raised, however, about the potential risks that wastewater surveillance might pose towards group privacy. Existing scholarship has focused upon using ethics- or human rights-based frameworks as a means of balancing the public health objectives of wastewater surveillance and the potential risks it might pose to group privacy. However, such frameworks greatly lack enforceability. In order to further the strong foundation laid by such frameworks - while addressing their lack of enforceability - this paper proposes the idea of the 'obligation' as an alternative way to regulate wastewater surveillance systems. The legal codification of said obligations provides a method of ensuring that wastewater surveillance systems can be deployed effectively and equitably. Our paper proposes that legal obligations for wastewater surveillance can be created and enforced through transparent and purposeful legislation (which would include limits on power and grant institutions substantial oversight) as well as paying heed to non-legislative legal means of enforcement, such as through courts or contracts. Introducing legal obligations for wastewater surveillance could therefore be highly useful to researchers, policymakers, corporate technologists, and government agencies working in this field.

Microbial community-based protein from soybean-processing wastewater as a sustainable alternative fish feed ingredient.

As the global demand for food increases, aquaculture plays a key role as the fastest growing animal protein sector. However, existing aquafeeds contain protein ingredients that are not sustainable under current production systems. We evaluated the use of microbial community-based single cell protein (SCP), produced from soybean processing wastewater, as a partial fishmeal protein substitute in juvenile Asian seabass (Lates calcarifer). A 24-day feeding trial was conducted with a control fishmeal diet and a 50% fishmeal replacement with microbial community-based SCP as an experimental group, in triplicate tanks containing 20 fish each. Both diets met the protein, essential amino acids (except for lysine), and fat requirements for juvenile Asian sea bass. The microbial composition of the SCP was dominated by the genera Acidipropionibacterium and Propioniciclava, which have potential as probiotics and producers of valuable metabolites. The growth performance in terms of percent weight gain, feed conversion ratio (FCR), specific growth rate (SGR), and survival were not significantly different between groups after 24 days. The experimental group had less variability in terms of weight gain and FCR than the control group. Overall, microbial community-based protein produced from soybean processing wastewater has potential as a value-added feed ingredient for sustainable aquaculture feeds.