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Carlos-Shanley, C.

Publications and source records attributed to Carlos-Shanley, C..

3 recordsLinked to original sources

Nutrient availability shifts the biosynthetic potential of soil-derived microbial communities

Secondary metabolites produced by microorganisms are the main source of antimicrobials other pharmaceutical drugs. Soil microbes have been the primary discovery source for these secondary metabolites, often producing complex organic compounds with specific biological activities. Research suggests that secondary metabolism broadly shapes microbial ecological interactions, but little is known about the factors that shape the abundance, distribution, and diversity of biosynthetic gene clusters in the context of microbial communities. In this study, we investigate the role of nutrient availability on the abundance of biosynthetic gene clusters in soil-derived microbial consortia. We found that soil microbial consortia enriched in medium with 150 mg/L of glucose and 200 mg/L of trehalose (here defined as high sugar) had more biosynthetic gene cluster and higher inhibitory activity than soil microbial consortia enriched in medium with 15 mg/L of glucose + 20 mg/L of trehalose (here defined as low sugar). Our results demonstrate that laboratory microbial communities are a promising tool to study ecology of specialized metabolites.

microbiology

A comparison of wild and captive Comal Springs riffle beetle (Heterelmis comalensis) microbiomes

The gut microbiome is affected by host intrinsic factors, diet, environment, and strongly linked to hosts health. Although fluctuations of microbiome composition are normal, some are due to changes in host environmental conditions. When species are moved into captive environments for conservation, education, or rehabilitation, these new conditions can influence a change in gut microbiome composition. Here, we compared the microbiomes of wild and captive Comal Springs riffle beetles (Heterelmis comalensis) by using amplicon sequencing of the 16S rRNA gene. We found that the microbiome of captive beetles was more diverse than wild beetle microbiomes. We identified 24 Amplicon Sequence Variants (ASVs) with relative abundances significantly different between the wild and captive beetles. Many of the ASVs overrepresented in captive beetle microbiomes belong to taxa linked to nitrogen-rich environments. This is one of the first studies comparing the effects of captivity on the microbiome of an endangered insect species. Our findings provide valuable information for future applications in the management of captive populations of H. comalensis.

microbiology

Experimental warming reduces gut prokaryotic diversity, survival and thermal tolerance of the eastern subterranean termite, Reticulitermes flavipes (Kollar)

Understanding the effects of environmental disturbances on the health and physiology of insects is crucial in predicting the impact of climate change on their distribution, abundance, and ecology. As microbial symbionts have been shown to play an integral role in a diversity of functions within the insect host, research examining how organisms adapt to environmental fluctuations should include their associated microbiota. Previous studies have shown that temperature affects the diversity of protists in termite gut, but less is known about the bacterial symbionts. In this study, subterranean termites (Reticulitermes flavipes (Kollar)) were exposed to three different temperature treatments characterized as low (15 {degrees}C), medium (27 {degrees}C), and high (35 {degrees}C). Results showed low temperature exposed termites had significantly lower CTmin and significantly higher SCP values compared to termites from medium or high temperature groups. This suggests that pre-exposure to cold allowed termites to stay active longer in decreasing temperatures but caused termites to freeze at higher temperatures. High temperature exposure had the most deleterious effects on termites with a significant reduction in termite survival as well as reduced ability to withstand cold stress. The microbial community of high temperature exposed termites showed a reduction in bacterial richness and decreased relative abundance of Spirochaetes, Elusimicrobia, and methanogenic Euryarchaeota. Our results indicate a potential link between gut bacterial symbionts and termites physiological response to environmental changes and highlight the need to consider microbial symbionts in studies relating to insect thermosensitivity.

microbiology