Detecting a significant amount of microorganisms in the troposphere

(scienceinfo.net) - Organisms in the atmosphere: Important microbial populations are found in the middle and convection layers.

In what is thought to be the first study of its kind, researchers have used genetic engineering to determine the presence of remarkable numbers of living microorganisms - mostly bacteria - In the middle and upper layers of the convection, this location is about 4 to 6 miles from the ground.

Whether or not microorganisms normally inhabit this area of ​​the atmosphere - perhaps life on carbon compounds is also found there - or whether or not living organisms have simply been trapped in the floor. This is derived from the surface of the earth yet to be known. This finding is of interest to atmospheric scientists because microorganisms can play a role in ice formation that may affect weather and climate. Long-distance transport of bacteria may also be a concern for disease transmission models.

Proven microorganisms exist in air samples as part of the GRIP program - NASA and Genesis Intensification (Genesis and Rapid Intensification Processes) to study blocks High-latitude and high-latitude gas associated with tropical storms.

Sampling was carried out from a DC 8 plane on both the mainland and the ocean, including the Caribbean and part of the Atlantic. The sampling process was carried out before, during and after two major tropical storms - Earl and Karl - in 2010.

Research supported by NASA and the National Science Foundation, will be published online in the Proceedings magazine of the National Academy of Sciences.

"We do not expect to find a lot of microorganisms in the troposphere because this floor is considered a difficult environment to survive life," Kostas Konstantinidis, an assistant professor at the School of Civil Engineering. and Environment at the Georgia Institute of Technology said. "It seems to be quite diverse in species, but not all bacteria take them above the troposphere."

On the aircraft, a filtration system designed by the research team collected particles - including microorganisms from the outside air entering the sampling probe of the aircraft.

Filters are analyzed using genetic techniques including polymerase chain reaction (PCR) and gene sequence, allowing researchers to detect microorganisms and estimate their numbers without It is necessary to use conventional cell culture techniques.

When the research air mass originated in the area above the oceans, scientists found in the sample mainly marine microorganisms.

Air masses in the mainland area mostly contain bacteria on the ground. The researchers also looked at strong evidence that storms had a significant impact on the distribution and dynamics of microbial populations.

Research shows that bacterial cells account for an average of about 20% of all detected particles that range in diameter from 0.25 to 1 micron. At least one representative sample is important, the bacteria are more crowded than the fungi in the samples, and the researchers found 17 different bacterial groups, some of which are likely to be The ability to metabolize common carbon compounds in air, such as oxalic acid.

Microorganisms may have an unspecified impact on cloud formation based on the addition (or replacement) of infertile particles, which normally act as nuclei to form. ice crystals, Athanasios Nenes, a professor at the Georgia School of Earth and Atmospheric Science and the School of Chemical and Molecular Biology.

"In the absence of sufficient dust or other materials as the nucleus for ice formation, only a small amount of surrounding microorganisms can facilitate ice formation at said heights. On and hygroscopic around , " Nenes said. "If they are the right size to form ice, they can affect the clouds around them."

Microorganisms are able to penetrate into the troposphere through the same processes of spreading sea dust and salt."When sea dust is created, it can carry bacteria because there are so many bacteria and organic substances on the surface of the ocean , " Nenes said.

The study brings together microbiologists, atmospheric modelers and environmental researchers to use the latest technologies to study DNA. In the future, researchers want to know if certain types of bacteria are more suitable to survive at these heights than other bacteria. Researchers also want to understand the role of microorganisms and determine whether these bacteria are performing tropospheric metabolic functions.

"Perhaps for these organisms the environmental conditions on this floor may not be harsh," Konstantinidis said. "I would not be surprised if there is life that works and grows in the clouds, but this is one thing we cannot say for sure now."

Other researchers have collected biological samples from the top of the mountain or from snow samples, but collecting biological materials from a jet requires a novel experimental setup. The researchers also had to look optimistic about how DNA extractions from biomass levels are much lower than what they usually study in soil or in lakes.

Nenes said: "We have proven that our technology works, and we can get some interesting information. A majority of particles in the atmosphere that are normally predicted to be dust or "Sea salt can actually be bacteria. At the moment we are only seeing what is there, so this is the beginning of things we hope to do."