Engineering topics

Hutchins, David A.

Publications and source records attributed to Hutchins, David A..

3 records

DOE OSTI2019

Scientists’ warning to humanity: microorganisms and climate change

In the Anthropocene, in which we now live, climate change is impacting most life on Earth. Microorganisms support the existence of all higher trophic life forms. To understand how humans and other life forms on Earth (including those we are yet to discover) can withstand anthropogenic climate change, it is vital to incorporate knowledge of the microbial ‘unseen majority’. We must learn not just how microorganisms affect climate change (including production and consumption of greenhouse gases) but also how they will be affected by climate change and other human activities. This Consensus Statement documents the central role and global importance of microorganisms in climate change biology. It also puts humanity on notice that the impact of climate change will depend heavily on responses of microorganisms, which are essential for achieving an environmentally sustainable future.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2019

Climate change microbiology — problems and perspectives

Here, the signs of climate change are undeniable, and the inevitable impact for Earth and all its inhabitants is a serious concern. Ice is melting, sea levels are rising, biodiversity is declining, precipitation has increased, atmospheric levels of carbon dioxide and greenhouse gases are alarmingly high, and extreme weather conditions are becoming increasingly common. But what role do microorganisms have in this global challenge? In this Viewpoint article, several experts in the field discuss the microbial contributions to climate change and consider the effects of global warming, extreme weather, flooding and other consequences of climate change on microbial communities in the ocean and soil, on host–microbiota interactions and on the global burden of infectious diseases and ecosystem processes, and they explore open questions and research needs.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2015

Trichodesmium genome maintains abundant, widespread noncoding DNA in situ, despite oligotrophic lifestyle

Understanding the evolution of the free-living, cyanobacterial, diazotroph Trichodesmium is of great importance due to its critical role in oceanic biogeochemistry and primary production. Unlike the other >150 available genomes of free-living cyanobacteria, only 63.8% of the Trichodesmium erythraeum (strain IMS101) genome is predicted to encode protein, which is 20-25% less than the average for other cyanobacteria and non-pathogenic, free-living bacteria. We use distinctive isolates and metagenomic data to show that low coding density observed in IMS101 is a common feature of the Trichodesmium genus both in culture and in situ. Transcriptome analysis indicates that 86% of the non-coding space is expressed, although the function of these transcripts is unclear. The density of noncoding, possible regulatory elements predicted in Trichodesmium , when normalized per intergenic kilobase, was comparable and two fold higher than that found in the gene dense genomes of the sympatric cyanobacterial genera Synechococcus and Prochlorococcus , respectively. Conserved Trichodesmium ncRNA secondary structures were predicted between most culture and metagenomic sequences lending support to the structural conservation. Conservation of these intergenic regions in spatiotemporally separated Trichodesmium populations suggests possible genus-wide selection for their maintenance. These large intergenic spacers may have developed during intervals of strong genetic drift caused by periodic blooms of a subset of genotypes, which may have reduced effective population size. In conclusion, our data suggest that transposition of selfish DNA, low effective population size, and high fidelity replication allowed the unusual ‘inflation’ of noncoding sequence observed in Trichodesmium despite its oligotrophic lifestyle.

59 BASIC BIOLOGICAL SCIENCES↗