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Bioaugmentation is commonly employed as a remediation technology. However, numerous studies indicate that introduced microorganisms often do not survive in the environment and thus do not increase contaminant remediation. This review details several new approaches that may increase the persistence and activity of exogenous microorganisms and/or genes following introduction into the environment. These techniques include: (1) bioaugmentation with cells encapsulated in a carrier such as alginate; (2) gene bioaugmentation where the goal is for the added inoculant to transfer remediation genes to indigenous microorganisms; (3) rhizosphere bioaugmentation where the microbial inoculant is added to the site along with a plant that serves as a niche for the inoculant's growth; and (4) phytoaugmentation where the remediation genes are engineered directly into a plant for use in remediation without a microbial inoculant. Additionally, the review discusses the generation of genetically engineered microorganisms for use in bioaugmentation along with methods for the control of the engineered microorganisms in the environment, and the potential effects of the release on indigenous organisms. Various methods for the detection of introduced microorganisms such as real-time polymerase chain reaction (PCR) and reporter genes are also addressed. Ultimately, these new approaches may broaden the application of bioaugmentation as a remediation technology.

Polyaromatic hydrocarbons (PAHs) are considered as hazardous organic priority pollutants. PAHs have immense public concern and critical environmental challenge around the globe due to their toxic, carcinogenic, and mutagenic properties, and their ubiquitous distribution, recalcitrance as well as persistence in environment. The knowledge about harmful effects of PAHs on ecosystem along with human health has resulted in an interest of researchers on degradation of these compounds. Whereas physico-chemical treatment of PAHs is cost and energy prohibitive, bioremediation i.e. degradation of PAHs using microbes is becoming an efficient and sustainable approach. Broad range of microbes including bacteria, fungi, and algae have been found to have capability to use PAHs as carbon and energy source under both aerobic and anaerobic conditions resulting in their transformation/degradation. Microbial genetic makeup containing genes encoding catabolic enzymes is responsible for PAH-degradation mechanism. The degradation capacity of microbes may be induced by exposing them to higher PAH-concentration, resulting in genetic adaptation or changes responsible for high efficiency towards removal/degradation. In last few decades, mechanism of PAH-biodegradation, catabolic gene system encoding catabolic enzymes, and genetic adaptation and regulation have been investigated in detail. This review is an attempt to overview current knowledge of microbial degradation mechanism of PAHs, its genetic regulation with application of genetic engineering to construct genetically engineered microorganisms, specific catabolic enzyme activity, and application of bioremediation for reclamation of PAH-contaminated sites. In addition, advanced molecular techniques i.e. genomic, proteomic, and metabolomic techniques are also discussed as powerful tools for elucidation of PAH-biodegradation/biotransformation mechanism in an environmental matrix.

There is considerable public and scientific debate for and against genetically modified (GM) crops. One of the first GM crops, Brassica napus (oilseed rape or canola) is now widely grown in North America, with proposed commercial release into Australia and Europe. Among concerns of opponents to these crops are claims that pollen movement will cause unacceptable levels of gene flow from GM to non-GM crops or to related weedy species, resulting in genetic pollution of the environment. Therefore, quantifying pollen-mediated gene flow is vital for assessing the environmental impact of GM crops. This study quantifies at a landscape level the gene flow that occurs from herbicide-resistant canola crops to nearby crops not containing herbicide resistance genes.

Genetically modified microorganisms (GMMs) can enable a wide range of important applications including environmental sensing and responsive engineered living materials. However, containment of GMMs to prevent environmental escape and satisfy regulatory requirements is a bottleneck for real-world use. While current biochemical strategies restrict unwanted growth of GMMs in the environment, there is a need for deployable physical containment technologies to achieve redundant, multi-layered and robust containment. We developed a hydrogel-based encapsulation system that incorporates a biocompatible multilayer tough shell and an alginate-based core. This deployable physical containment strategy (DEPCOS) allows no detectable GMM escape, bacteria to be protected against environmental insults including antibiotics and low pH, controllable lifespan and easy retrieval of genomically recoded bacteria. To highlight the versatility of DEPCOS, we demonstrated that robustly encapsulated cells can execute useful functions, including performing cell–cell communication with other encapsulated bacteria and sensing heavy metals in water samples from the Charles River. A dual-layer encapsulation approach provides physical containment of genetically modified bacteria (especially when combined with chemical containment) while also protecting them from environmental stressors and maintaining their sensing functions.

Wild and managed pollinators provide a wide range of benefits to society in terms of contributions to food security, farmer and beekeeper livelihoods, social and cultural values, as well as the maintenance of wider biodiversity and ecosystem stability. Pollinators face numerous threats, including changes in land-use and management intensity, climate change, pesticides and genetically modified crops, pollinator management and pathogens, and invasive alien species. There are well-documented declines in some wild and managed pollinators in several regions of the world. However, many effective policy and management responses can be implemented to safeguard pollinators and sustain pollination services. Wild and managed pollinators are threatened by pressures such as environmental changes and pesticides, leading to risks for pollinator-dependent crop production, meaning more research and better policies are needed to safeguard pollinators and their services. Take care of the pollinators Pollinators provide numerous goods and services to society, and help to maintain ecosystem health and function, but their numbers are in decline in several parts of the world. In this Review, Simon Potts et al . synthesize data on the current status of pollinators, outline the main drivers of their decline, and discuss the policy and management intervention that can help to safeguard their survival.

Products derived from agricultural biotechnology is fast becoming one of the biggest agricultural trade commodities globally, clothing us, feeding our livestock, and fueling our eco-friendly cars. This exponential growth occurs despite asynchronous regulatory schemes around the world, ranging from moratoriums and prohibitions on genetically modified (GM) organisms, to regulations that treat both conventional and biotech novel plant products under the same regulatory framework. Given the enormous surface area being cultivated, there is no longer a question of acceptance or outright need for biotech crop varieties. Recent recognition of the researchers for the development of a genome editing technique using CRISPR/Cas9 by the Nobel Prize committee is another step closer to developing and cultivating new varieties of agricultural crops. By employing precise, efficient, yet affordable genome editing techniques, new genome edited crops are entering country regulatory schemes for commercialization. Countries which currently dominate in cultivating and exporting GM crops are quickly recognizing different types of gene-edited products by comparing the products to conventionally bred varieties. This nuanced legislative development, first implemented in Argentina, and soon followed by many, shows considerable shifts in the landscape of agricultural biotechnology products. The evolution of the law on gene edited crops demonstrates that the law is not static and must adjust to the mores of society, informed by the experiences of 25 years of cultivation and regulation of GM crops. The crux of this review is a consolidation of the global legislative landscape on GM crops, as it stands, building on earlier works by specifically addressing how gene edited crops will fit into the existing frameworks. This work is the first of its kind to synthesize the applicable regulatory documents across the globe, with a focus on GM crop cultivation, and provides links to original legislation on GM and gene edited crops.

Main conclusion While transgenic technology has heralded a new era in crop improvement, several concerns have precluded their widespread acceptance. Alternative technologies, such as cisgenesis and genome-editing may address many of such issues and facilitate the development of genetically engineered crop varieties with multiple favourable traits. Genetic engineering and plant transformation have played a pivotal role in crop improvement via introducing beneficial foreign gene(s) or silencing the expression of endogenous gene(s) in crop plants. Genetically modified crops possess one or more useful traits, such as, herbicide tolerance, insect resistance, abiotic stress tolerance, disease resistance, and nutritional improvement. To date, nearly 525 different transgenic events in 32 crops have been approved for cultivation in different parts of the world. The adoption of transgenic technology has been shown to increase crop yields, reduce pesticide and insecticide use, reduce CO 2 emissions, and decrease the cost of crop production. However, widespread adoption of transgenic crops carrying foreign genes faces roadblocks due to concerns of potential toxicity and allergenicity to human beings, potential environmental risks, such as chances of gene flow, adverse effects on non-target organisms, evolution of resistance in weeds and insects etc. These concerns have prompted the adoption of alternative technologies like cisgenesis, intragenesis, and most recently, genome editing. Some of these alternative technologies can be utilized to develop crop plants that are free from any foreign gene hence, it is expected that such crops might achieve higher consumer acceptance as compared to the transgenic crops and would get faster regulatory approvals. In this review, we present a comprehensive update on the current status of the genetically modified (GM) crops under cultivation. We also discuss the issues affecting widespread adoption of transgenic GM crops and comment upon the recent tools and techniques developed to address some of these concerns.

Although Americans generally hold science in high regard and respect its findings, for some contested issues, such as the existence of anthropogenic climate change, public opinion is polarized along religious and political lines. We ask whether individuals with more general education and greater science knowledge, measured in terms of science education and science literacy, display more (or less) polarized beliefs on several such issues. We report secondary analyses of a nationally representative dataset (the General Social Survey), examining the predictors of beliefs regarding six potentially controversial issues. We find that beliefs are correlated with both political and religious identity for stem cell research, the Big Bang, and human evolution, and with political identity alone on climate change. Individuals with greater education, science education, and science literacy display more polarized beliefs on these issues. We find little evidence of political or religious polarization regarding nanotechnology and genetically modified foods. On all six topics, people who trust the scientific enterprise more are also more likely to accept its findings. We discuss the causal mechanisms that might underlie the correlation between education and identity-based polarization.

Bacteria and fungi are used industrially to produce commodity fine chemicals at vast scale. Sugars are an economical feedstock, but many of the desired products require enzymatic reduction, meaning that some of the sugar must be diverted to regenerate the cellular reductant NADPH (reduced form of nicotinamide adenine dinucleotide phosphate). Guo et al. show that electrons from light-sensitive nanoparticles can drive reduction of cellular NADPH in yeast, which can then be used for reductive biosynthetic reactions. This system can reduce diversion of carbon to NADPH regeneration and should be compatible with many existing engineered strains of yeast. Science , this issue p. 813 Light-harvesting nanoparticles power reduction reactions in genetically engineered yeast. Inorganic-biological hybrid systems have potential to be sustainable, efficient, and versatile chemical synthesis platforms by integrating the light-harvesting properties of semiconductors with the synthetic potential of biological cells. We have developed a modular bioinorganic hybrid platform that consists of highly efficient light-harvesting indium phosphide nanoparticles and genetically engineered Saccharomyces cerevisiae , a workhorse microorganism in biomanufacturing. The yeast harvests photogenerated electrons from the illuminated nanoparticles and uses them for the cytosolic regeneration of redox cofactors. This process enables the decoupling of biosynthesis and cofactor regeneration, facilitating a carbon- and energy-efficient production of the metabolite shikimic acid, a common precursor for several drugs and fine chemicals. Our work provides a platform for the rational design of biohybrids for efficient biomanufacturing processes with higher complexity and functionality.

Despite the rapid adoption of genetically modified (GM) crops by farmers in many countries, controversies about this technology continue. Uncertainty about GM crop impacts is one reason for widespread public suspicion. We carry out a meta-analysis of the agronomic and economic impacts of GM crops to consolidate the evidence. Original studies for inclusion were identified through keyword searches in ISI Web of Knowledge, Google Scholar, EconLit, and AgEcon Search. Studies were included when they build on primary data from farm surveys or field trials anywhere in the world, and when they report impacts of GM soybean, maize, or cotton on crop yields, pesticide use, and/or farmer profits. In total, 147 original studies were included. Analysis of mean impacts and meta-regressions to examine factors that influence outcomes. On average, GM technology adoption has reduced chemical pesticide use by 37%, increased crop yields by 22%, and increased farmer profits by 68%. Yield gains and pesticide reductions are larger for insect-resistant crops than for herbicide-tolerant crops. Yield and profit gains are higher in developing countries than in developed countries. Several of the original studies did not report sample sizes and measures of variance. The meta-analysis reveals robust evidence of GM crop benefits for farmers in developed and developing countries. Such evidence may help to gradually increase public trust in this technology.