Publications by authors named "HANDELSMAN J"

Unlabelled: The underlying interactions that occur to maintain skin microbiome composition, function, and overall skin health are largely unknown. Often, these types of interactions are mediated by microbial metabolites. Cobamides, the vitamin B family of cofactors, are essential for metabolism in many bacteria but are only synthesized by a fraction of prokaryotes, including certain skin-associated species.

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Unlabelled: Mediation analysis has emerged as a versatile tool for answering mechanistic questions in microbiome research because it provides a statistical framework for attributing treatment effects to alternative causal pathways. Using a series of linked regressions, this analysis quantifies how complementary data relate to one another and respond to treatments. Despite these advances, existing software's rigid assumptions often result in users viewing mediation analysis as a black box.

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Multispecies microbial communities drive most ecosystems on Earth. Chemical and biological interactions within these communities can affect the survival of individual members and the entire community. However, the prohibitively high number of possible interactions within a microbial community has made the characterization of factors that influence community development challenging.

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Biofilms are three-dimensional structures containing one or more bacterial species embedded in extracellular polymeric substances. Although most biofilms are stationary, forms a motile spherical biofilm called a zorb, which is propelled by its base cells and contains a polysaccharide core. Here, we report formation of spatially organized, motile, multispecies biofilms, designated "co-zorbs," that are distinguished by a core-shell structure.

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Purpose: Although early identification of pediatric hearing loss is crucial, a formal online training course has not been freely accessible to a global audience. In response, we created a novel course for health professionals worldwide.

Method: Course development occurred from February 2019 to May 2020.

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The underlying interactions that occur to maintain skin microbiome composition, function, and overall skin health are largely unknown. Often, these types of interactions are mediated by microbial metabolites. Cobamides, the vitamin B family of cofactors, are essential for metabolism in many bacteria, but are only synthesized by a small fraction of prokaryotes, including certain skin-associated species.

View Article and Find Full Text PDF

Mediation analysis has emerged as a versatile tool for answering mechanistic questions in microbiome research because it provides a statistical framework for attributing treatment effects to alternative causal pathways. Using a series of linked regressions, this analysis quantifies how complementary data relate to one another and respond to treatments. Despite these advances, existing software's rigid assumptions often result in users viewing mediation analysis as a black box.

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is recognized for its ability to colonize diverse habitats and cause disease in a variety of hosts, including plants, invertebrates, and mammals. Understanding how this bacterium is able to occupy wide-ranging niches is important for deciphering its ecology. We used transposon sequencing [Tn-Seq, also known as insertion sequencing (INSeq)] to identify genes in that contribute to fitness during the colonization of .

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Unlabelled: is a ubiquitous soil and rhizosphere bacterium, but despite its abundance, the factors contributing to its success in communities are poorly understood. Using a model microbial community, he itchhikers f the hizosphere (THOR), we determined the effects of colonization on the fitness of in the community. Insertion sequencing, a massively parallel transposon mutant screen, on sterile sand identified 25 genes likely to be important for surface colonization.

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is recognized for its ability to colonize diverse habitats and cause disease in a variety of hosts, including plants, invertebrates, and mammals. Understanding how this bacterium is able to occupy wide-ranging niches is important for deciphering its ecology. We used transposon sequencing (Tn-Seq, also known as INSeq) to identify genes in that contribute to fitness during colonization of .

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Bacterial secondary metabolites are a major source of antibiotics and other bioactive compounds. In microbial communities, these molecules can mediate interspecies interactions and responses to environmental change. Despite the importance of secondary metabolites in human health and microbial ecology, little is known about their roles and regulation in the context of multispecies communities.

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Scientists are expected to engage with the public, especially when society faces challenges like the COVID-19 pandemic or climate change, but what public engagement means to scientists is not clear. We use a triangulated, mixed-methods approach combining survey and focus group data to gain insight into how pre-tenure and tenured scientists personally conceptualize public engagement. Our findings indicate that scientists' understanding of public engagement is similarly complex and diverse as the scholarly literature.

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The idea of faculty engaging in meaningful dialogue with different publics instead of simply communicating their research to interested audiences has gradually morphed from a novel concept to a mainstay within most parts of the academy. Given the wide variety of public engagement modalities, it may be unsurprising that we still lack a comprehensive and granular understanding of factors that influence faculty willingness to engage with public audiences. Those nuances are not always captured by quantitative surveys that rely on pre-determined categories to assess scholars' willingness to engage.

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Genome mining has become an invaluable tool in natural products research to quickly identify and characterize the biosynthetic pathways that assemble secondary or specialized metabolites. Recently, evolutionary principles have been incorporated into genome mining strategies in an effort to better assess and prioritize novelty and understand their chemical diversification for engineering purposes. Here, we provide an introduction to the principles underlying evolutionary genome mining, including bioinformatic strategies and natural product biosynthetic databases.

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Gateway college science courses continue to exclude students from science, disproportionately discriminating against students of color. As the higher education system strives to reduce discrimination, we need a deliberate, iterative process to modify, supplement, or replace current modalities. By incorporating antiracist, just, equitable, diverse, and inclusive (AJEDI) principles throughout course design, instructors create learning environments that provide an antidote to historically oppressive systems.

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Microbial interactions dictate the structure and function of microbiomes, but the complexity of natural communities can obscure the individual interactions. Model microbial communities constructed with genetically tractable strains known to interact in natural settings can untangle these networks and reveal underpinning mechanisms. Our model system, he itchhikers f the hizosphere (THOR), is composed of three species-Bacillus cereus, Flavobacterium johnsoniae, and Pseudomonas koreensis-that co-isolate from field-grown soybean roots.

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Covering: up to 2021Natural products research is in the midst of a renaissance ushered in by a modern understanding of microbiology and the technological explosions of genomics and metabolomics. As the exploration of uncharted chemical space expands into high-throughput discovery campaigns, it has become increasingly clear how design elements influence success: (bio)geography, habitat, community dynamics, culturing/induction methods, screening methods, dereplication, and more. We explore critical considerations and assumptions in natural products discovery.

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Bacterial biofilms are aggregates of surface-associated cells embedded in an extracellular polysaccharide (EPS) matrix, and are typically stationary. Studies of bacterial collective movement have largely focused on swarming motility mediated by flagella or pili, in the absence of a biofilm. Here, we describe a unique mode of collective movement by a self-propelled, surface-associated biofilm-like multicellular structure.

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The world faces two seemingly unrelated challenges-a shortfall in the STEM workforce and increasing antibiotic resistance among bacterial pathogens. We address these two challenges with Tiny Earth, an undergraduate research course that excites students about science and creates a pipeline for antibiotic discovery.

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Untargeted mass spectrometry is employed to detect small molecules in complex biospecimens, generating data that are difficult to interpret. We developed Qemistree, a data exploration strategy based on the hierarchical organization of molecular fingerprints predicted from fragmentation spectra. Qemistree allows mass spectrometry data to be represented in the context of sample metadata and chemical ontologies.

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Virtual conferences can offer significant benefits but require considerable planning and creativity to be successful. Here we describe the successes and failures of a hybrid in-person/virtual conference model. The COVID-19 epidemic presents the scientific community with an opportunity to pioneer novel models that effectively engage virtual participants to advance conference goals.

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Antibiotics produced by bacteria play important roles in microbial interactions and competition Antibiosis can induce resistance mechanisms in target organisms, and at sublethal doses, antibiotics have been shown to globally alter gene expression patterns. Here, we show that hygromycin A from sp. strain 2AW.

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