New Window Opens on the Secret Life of Microbes: Scientists Develop First Microbial Profiles of Ecosystems

Nowhere is the principle of "strength in numbers" more apparent than in the collective power of microbes: despite their simplicity, these one-cell organisms--which number about 5 million trillion trillion strong (no, that is not a typo) on Earth--affect virtually every ecological process, from the decay of organic material to the production of oxygen.

But even though microbes essentially rule the Earth, scientists have never before been able to conduct comprehensive studies of microbes and their interactions with one another in their natural habitats. Now, a new study--funded by the National Science Foundation (NSF) and described in the March 12, 2008 online issue of Nature--provides the first inventories of microbial capabilities in nine very different types of ecosystems, ranging from coral reefs to deep mines.

"These new microbial inventories provide a new and important window into ecosystems and how they respond to stresses, such as pesticide runoff and invasive species," said Lita Proctor, an NSF program director.

Rather than identifying the kinds of microbes live in each ecosystem, the study catalogued each ecosystem's microbial "know-how," captured in its DNA, for conducting metabolic processes, such as respiration, photosynthesis and cell division. These microbial catalogues are more distinctive than the identities of resident microbes. "Now microbes can be studied by what they can do not who they are," said Proctor.

This microbial study employed the principles of metagenomics, a powerful new method of analysis that characterizes the DNA content of entire communities of organisms rather than individual species. One of the main advantages of metagenomics is that it enables scientists to study microbes--most of which cannot be grown in the laboratory--in their natural habitats.

Specifically, the microbial study produced the following results:

A unique, identifying microbial fingerprint for each of nine different types of ecosystems. Each ecosystem's fingerprint was based on its unique suit of microbial capabilities.Methods for early detection of ecological responses to environmental stresses. Such methods are based on the principle that "microbes grow faster and so respond to environmental stresses more quickly than do other types of organisms," said Forest Rohower of San Diego State University, a member of the research team. Because microbes are an ecosystem's first-responders, by monitoring changes in an ecosystem's microbial capabilities, scientists can detect ecological responses to stresses earlier than would otherwise be possible--even before such responses might be visibly apparent in plants or animals, Rohower said. Evidence that viruses serve as the gene banks for ecosystems. This evidence includes observations that viruses in the nine ecosystems carried large loads of DNA without using such DNA themselves. Rohower believes that the viruses probably transfer such excess DNA to bacteria during infections, and thereby pass on "new genetic tricks" to their microbial hosts. The study also indicates that by transporting the DNA to new locations, viruses may serve as important agents in the evolution of microbes.

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"Telework" Benefits Employers, Employees and the Environment

The Telework ExchangeSM, a public-private partnership focused on telework, and the National Science Foundation (NSF), today announced the results of a joint study, "Telework Under the Microscope--A Report on the National Science Foundation's Telework Program."  Based on survey responses from 87 percent of NSF's employees, the study shows that telework is a win-win-win for managers, employees and the environment.Among top-level findings, the study reveals that ... More at http://www.nsf.gov/news/news_summ.jsp?cntn_id=111252&govDel=USNSF_51 This is an NSF News item.

High-School Scientists Decode DNA Sequence, Present Findings

Opportunities for high school students to do research as part of a science class are--sadly--all too rare. Where such opportunities do exist, students often find themselves going through the motions of an experiment with a predetermined outcome.Against this backdrop, imagine a project where students can work in a rapidly advancing field, doing original research, then publish their results and share them with the scientific community. About 300 New Jersey high school students have such ... More at http://www.nsf.gov/news/news_summ.jsp?cntn_id=111243&govDel=USNSF_51 This is an NSF News item.

Memory on Trial

The U.S. legal system has long assumed that all testimony is not equally credible, that some witnesses are more reliable than others. In tough cases with child witnesses, it assumes adult witnesses to be more reliable. But what if the legal system had it wrong?Researchers Valerie Reyna, human development professor, and Chuck Brainerd, human development and law school professor-- both from Cornell University -- argue that like the two-headed Roman god Janus, memory is of two ... More at http://www.nsf.gov/news/news_summ.jsp?cntn_id=111230&govDel=USNSF_51 This is an NSF News item.

Attend Capital Science 2008, a Premier Showcase of Scientific Talent, at NSF

Do you want to learn about timely, dynamic scientific issues straight from leading experts? If so, attend Capital Science (CapSci) 2008 on Saturday and Sunday, March 29-30, 2008, at the National Science Foundation (NSF) in Arlington, Va., near the Ballston Metro stop.  This event--which is sponsored by the Washington Academy of Sciences--should appeal to scientists, researchers, professors, students, policy-makers, government professionals, reporters, ... More at http://www.nsf.gov/news/news_summ.jsp?cntn_id=111233&govDel=USNSF_51 This is an NSF News item.

Tax Rebates Versus Tax Bonuses

On Feb. 13, 2008, the president signed a $168 billion stimulus package designed to give $300, $600 or $1,200 checks to more than 100 million Americans. It was the second time in seven years that lawmakers agreed to return additional tax money in hopes that people would spend it to stimulate a sluggish economy. A key question: Will those receiving checks spend enough to have the desired effect?Economic theory says "yes" -- give people money and they will spend it. ... More at http://www.nsf.gov/news/news_summ.jsp?cntn_id=111197&govDel=USNSF_51 This is an NSF News item.