Researchers have discovered organic molecules trapped in an incredible ancient rock formation in Australia, indicating that what they are saying is the first detailed evidence of the earliest chemical composition that may form the basis of the earth’s primitive microbial life forms .
The discovery was made by Pilbara Craton in Western Australia in the 3.5 billion-year-old Dresser rock formation. This discovery adds a large number of research results that point to this ancient part of the world. , This area is only one of the two original bare deposits in the area. It can be traced back to the earth of the ancient times.
In recent years, the hydrothermal rocks in the Dresser formation have repeatedly signaled that it seems to be the earliest known life on land. Scientists have discovered “conclusive evidence”
Now, in a new study, German researchers have discovered specific chemical traces that may allow this primitive organism to exist, and discovered a barite deposit (a mineral formed through various processes (including hydrothermal phenomena)) Organic molecules related to biology.
Helge Mißbach, a geobiologist at the University of Cologne, Germany, explained: “In the field, barite is directly related to the fossil microbial mat. When they are scratched, they smell like rotten eggs.”
“Therefore, we suspect that the organic matter they contain may be the nutrients for early microbial life.”
Although scientists have long hypothesized how organic molecules act as substrates for primitive microorganisms and their metabolic processes, so far, direct evidence has proven to be largely elusive.
To investigate, Mißbach and his researchers examined the inclusions in the barite of the Dreiser Formation. These chemically stable minerals can preserve the fluids and gases in the rock for billions of years.
Researchers used a variety of techniques to analyze barite samples-including gas chromatography-mass spectrometry, microcalorimetry, and stable isotope analysis. The researchers discovered what they described as “organic with known or inferred metabolic correlations.” Interesting diversity of molecules”.
These include the organic compounds acetic acid and methyl mercaptan, and a variety of gases (including hydrogen sulfide) that may come from biological or non-biological sources.
Above: Barite rock, indicating that it is closely related to stromatolites.
Although the exact connection may not be determined, the close proximity of these inclusions to barite and adjacent organic matter (stromatolite) suggests that ancient chemicals once carried in the hydrothermal fluid may have affected primitive microorganisms Community.
The researchers wrote in the study: “In fact, many compounds found in fluid inclusions encapsulated by barite… will provide an ideal substrate for the sulfur-based and methanogenic microorganisms previously proposed as Dreiser environments. .”
In addition to chemicals that may act as nutrients or substrates, other compounds found in the contents may also serve as the “cornerstones” of various carbon-based chemical reactions, which may promote the metabolism of microorganisms by generating energy, such as Lipids can be broken down by life forms.
The research team explained: “In other words, the basic component of methyl thioacetate is the proposed key agent for emergence of life, which can be used in the Dresser environment.”
“They may have conveyed the basis of chemical autotrophic carbon fixation, and thus absorbed carbon synthesis and metabolism into biomass.”
The findings are reported in Nature Communications.