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ABSTRACT The complete genome ofPlanococcus koreensiswas obtained using Nanopore MinION sequencing after isolation from soil in Colorado. The assembled genome contains one circular contig with 3,519,105 bp, 3,606 genes, 419 pseudogenes, and 47.62% guanine-cytosine content. This discovery provides a fully assembledP. koreensisgenome available at the National Center for Biotechnology Information. 

Summary Use of synthetic microbial communities (SynComs) is a promising approach that harnesses nature‐based solutions to support soil fertility and food security, mitigate climate change impacts, and restore terrestrial ecosystems. Several microbial products are in the market, and many others are at different stages of development and commercialization. Yet, we are still far from being able to fully harness the potential and successful applications of such biotechnological tools. The limited field efficiency and efficacy of SynComs have significantly constrained commercial opportunities, resulting in market growth falling below expectations. To overcome these challenges and manage expectations, it is critical to address current limitations, failures, and potential environmental consequences of SynComs. In this Viewpoint, we explore how using multiple eco‐evolutionary theories can inform SynCom design and success. We further discuss the current status of SynComs and identify the next steps needed to develop and deploy the next generation of tools to boost their ability to support multiple ecosystem services, including food security and environmental sustainability. 

ABSTRACT Aerobiology research focusing on bioaerosol particle dynamics has catalogued the identity, distribution, and abundance of airborne microbes in a broad variety of indoor environments and, more recently, indoor disinfection methods for medically relevant microbes. Given their importance in environmental health and our constant exposure to airborne microbes in our daily lives, surprisingly little is known about the activity of live bioaerosols and their metabolic responses to aerosolization and suspension stress. In this context, microbial messenger RNA (mRNA) is a powerful information source of near-real-time organismal responses that cannot be attained through genomic, proteomic, or metabolomic studies. This review discusses current knowledge from transcriptomic studies describing airborne bacterial cellular activity in response to a myriad of environmental stresses imparted rapidly upon aerosolization and continued suspension as a microscopic bioaerosol. In the context of transcriptome profiling, potential artifacts associated with aerosolization/collection of bioaerosols are discussed from the perspective of preserving mRNA and maintaining its fidelity as it exists in airborne microbes. Recommendations for advancing live bioaerosol metabolic profiling through gene expression studies are presented to mitigate inherent artifacts and challenges with modern bioaerosol experiments. These recommendations include the use of larger experimental chambers, temperature control during aerosolization processes, and liquid capture bioaerosol sampling into a nucleic acid preservative to improve the fidelity of collected RNA and better capture the transcriptional activity of airborne microorganisms. Eventually, improvements in profiling bioaerosol activity can contribute toward answering fundamental questions on the aerobiome such as: is the atmosphere a temporary highway or a habitat for microorganisms? 

Abstract Ice‐nucleating particles (INPs) play a key role in ice formation and cloud microphysics and thus significantly impact the water cycle and the climate. However, our understanding of atmospheric INPs, particularly their sources, emissions, and spatiotemporal variability, is incomplete. While the enhancement of atmospheric INP concentrations with rainfall has been previously shown, a mechanistic understanding of the process is lacking. Here, we link detailed precipitation observations with near‐surface atmospheric INP concentrations at a semiarid grassland site in Colorado. Considering the during‐precipitation air samples, INP concentrations positively correlate with cumulative rainfall kinetic energy and amount, suggesting that INP aerosolization is induced by raindrop and hailstone impact. By additionally analyzing the INP content of precipitation water, terrestrial source samples, and heat‐treated samples, we demonstrate that local plants are the most plausible source of rain‐induced INPs during a precipitation event. Should INPs aerosolized by precipitation rise to cloud height, they could influence cloud ice fraction and initiate precipitation resulting in an aerosol‐cloud‐precipitation feedback. 

Abstract Genomic information is now available for a broad diversity of bacteria, including uncultivated taxa. However, we have corresponding knowledge on environmental preferences (i.e. bacterial growth responses across gradients in oxygen, pH, temperature, salinity, and other environmental conditions) for a relatively narrow swath of bacterial diversity. These limits to our understanding of bacterial ecologies constrain our ability to predict how assemblages will shift in response to global change factors, design effective probiotics, or guide cultivation efforts. We need innovative approaches that take advantage of expanding genome databases to accurately infer the environmental preferences of bacteria and validate the accuracy of these inferences. By doing so, we can broaden our quantitative understanding of the environmental preferences of the majority of bacterial taxa that remain uncharacterized. With this perspective, we highlight why it is important to infer environmental preferences from genomic information and discuss the range of potential strategies for doing so. In particular, we highlight concrete examples of how both cultivation-independent and cultivation-dependent approaches can be integrated with genomic data to develop predictive models. We also emphasize the limitations and pitfalls of these approaches and the specific knowledge gaps that need to be addressed to successfully expand our understanding of the environmental preferences of bacteria. 

Abstract Recent studies have suggested that microbial aerosolization in wildfire smoke is an understudied source of microbes to the atmosphere. Wildfire smoke can travel thousands of kilometers from its source with the potential to facilitate the transport of microbes, including microbes that can have far‐reaching impacts on human or ecosystem health. However, the relevance of longer‐range detection of microbes in smoke plumes remains undetermined, as previous studies have mainly focused on analyses of bioaerosols collected adjacent to or directly above wildfires. Therefore, we investigated whether wildfire smoke estimated to originate >30 km from different wildfire sources would contain detectable levels of bacterial and fungal DNA at ground level, hypothesizing that smoke‐impacted air would harbor greater amounts and a distinct composition of microbes as compared to ambient air. We used cultivation‐independent approaches to analyze 150 filters collected over time from three sampling locations in the western United States, of which 34 filters were determined to capture wildfire smoke events. Contrary to our hypothesis, smoke‐impacted samples harbored lower amounts of microbial DNA. Likewise, there was a limited signal in the composition of the microbial assemblages detected in smoke‐affected samples as compared to ambient air, but we did find that changes in humidity were associated with temporal variation in the composition of the bacterial and fungal bioaerosols. With our study design, we were unable to detect a robust and distinct microbial signal in ground‐level smoke originating from distant wildfires. 

Soil organisms represent the most abundant and diverse organisms on the planet and support almost every ecosystem function we know, and thus impact our daily lives. Some of these impacts have been well-documented, such as the role of soil organisms in regulating soil fertility and carbon sequestration; processes that have direct implications for essential ecosystem services including food security and climate change mitigation. Moreover, soil biodiversity also plays a critical role in supporting other aspects from One Health—the combined health of humans, animals, and the environment—to the conservation of historic structures such as monuments. Unfortunately, soil biodiversity is also highly vulnerable to a growing number of stressors associated with global environmental change. Understanding how and when soil biodiversity supports these functions, and how it will adapt to changing environmental conditions, is crucial for conserving soils and maintaining soil processes for future generations. In this Essay, we discuss the fundamental importance of soil biodiversity for supporting multiple ecosystem services and One Health, and further highlight essential knowledge gaps that need to be addressed to conserve soil biodiversity for the next generations.