One of the most detailed genomic study is conducted which is revealing an underground world of stunning bacteria’s microbial diversity. It has added dozens of newer branches to the tree of life.
Bacterial Bonanza is coming from scientists who has reconstructed the genomes of more than 2,500 microbes from the sediments and groundwater samples. These samples obtained were collected at the aquifer in Colorado.
Newer Diversity of Bacteria Discovered:
Effort was led by researchers of Department of Energy’s Lawrence Berkeley National Laboratory and UC Berkeley. DNA sequencing was performed further at the Joint Genome Institute, a DOE office of Science User Facility.
As being reported online on 24th October in the journal Nature Communications, scientists has netted genomes from 80 percent of all known bacterial phyla. It is one of the remarkable degree of biological diversity at one location.
They are also further discovering 47 new phylum level bacterial groups while naming many of them after the influential microbiologists and other scientists. They even learned regarding the newer insights about how microbial communities are working to drive processes which are critical to planet’s climate and life everywhere.
These findings are shedding light over one of the Earth’s most important and least understood remains of life. The subterranean world is hosting up to one fifth of all biomass but it is remaining a mystery.
Jill Banfield, a Senior Faculty Scientist in Berkeley Lab’s Climate & Ecosystem Sciences Division and a UC Berkeley professor in the departments of Earth and Planetary Science, and Environmental Science, Policy, and Management says, “We didn’t expect to find this incredible microbial diversity. But then again, we know little about the roles of subsurface microbes in bio-geo-chemical processes, and more broadly, we don’t really know what’s down there.”
UC Berkeley’s Karthik Anantharaman being first author of the study says, “To better understand what subsurface microbes are up to, our approach is to access their entire genomes. This enabled us to discover a greater interdependence among microbes than we’ve seen before.”
This study is a part of the Berkeley’s lab-led project which is called Sustainable Systems Scientific Focus Area 2.0. It is developing a predictive understanding of the terrestrial environments from genome to the watershed scale.
Field research of the project taken place at the research site near the town of Rifle, Colorado. Here since the past several years scientists have conducted experiments which were designed for stimulating populations of subterranean microbes. Scientists sent soil and water samples from these experiments to the Joint Genome Institute for terabase-scale metagenomic sequencing.
Study of Environmental DNA Samples:
This high-throughput method is further isolating and purifying DNA from the environmental samples. It is further sequencing about one trillion base pairs of DNA one at a time. Further, scientists has used bioinformatics tools which were further developed in Banfield’s lab for analysing data.
This approach has redrawn the tree of life. Between the 47 newer groups of bacteria reported in this work and 35 newer groups published last year. Banfield’s team has doubled the number of known bacterial groups.
With the discovery comes the naming rights. Scientists has even named many of the newer bacteria groups after Berkeley Lab and UC Berkeley researchers.
For example, there’s candidates Andersenbacteria after the phylochip inventor Gary Anderson and there’s Candidatus Doudnabacteria, after CRISPR genomeediting pioneer Jennifer Doudna.
Banfield in a nod to the sixteen elements being discovered at Berkeley Lab and UC Berkeley says, “Berkeley now dominates the tree of life as it does the periodic table.”
Another big outcome includes deeper understanding of the roles of subsurface microbes which plays in the globally important carbon, hydrogen, nitrogen and sulphur cycles.
Information obtained will be helping for better representing these cycles in predictive models which includes climatic simulations.
Scientists have conducted metabolic analysis of about 36 percent of the organisms being detected in the aquifer system.
Analysis of Microbes in various Layers of Earth’s Crust:
They were focusing over the phenomenon called metabolic hand off which specifically means that one microbe’s waste is another microbe’s food.
It’s quite known for the case of lab studies that the hand-offs are needed in certain reactions, yet these interconnected networks are widespread and are vastly more complex in real world.
For understanding why its quite important for representing the metabolic hand offs accurately as possible in models, considering nitrate which is groundwater contaminant from fertilisers.
Subsurface microbes are also the primary driver in terms of reducing the nitrate to harmless nitrogen gas.
There are about four steps in these denitrification process and the third step of the same is creating nitrous oxide – which is one of the most potent greenhouse gas.
Process is breaking down if the microbes which can carry out the fourth step are quite inactive when the pulse of nitrate enters the system.
Anantharaman further adding says, “If microbes aren’t there to accept the nitrous oxide handoff, then the greenhouse gas escapes into the atmosphere.” Scientists has found carbon, hydrogen, nitrogen and sulphur cycles which are all driven by metabolic hand offs. This are specifically requiring an unexpectedly higher degree of interdependence among the microbes.
Vast majority of microorganisms can’t fully reduce a compound on their own and requires a team. There are even the backup microbes ready for performing hand off if first-string microbes are unavailable.
Banfield commenting over it says, “The combination of high microbial diversity and interconnections through metabolic hand offs likely results in high ecosystem resilience.”