June 21, 2016 | David F. Coppedge

Precambrian Protein Identified

They say it’s almost two billion (with a B) years old, yet it resembles modern counterparts.

The Gunflint Chert in Canada has long been a hot spot for microbe hunters. J. William Schopf identified microbial fossils in these rocks years ago. Only recently, however, have scientists been able to probe the structure of molecules within the fossils. Not all of the living material has been permineralized (that is, replaced by minerals such as silicates). Unbelievably, there are still traces of the original organic molecules present, as reported in Nature Communications by Alleon et al. “Molecular preservation of 1.88 Ga Gunflint organic microfossils as a function of temperature and mineralogy.”

The significant degradation that fossilized biomolecules may experience during burial makes it challenging to assess the biogenicity of organic microstructures in ancient rocks. Here we investigate the molecular signatures of 1.88 Ga Gunflint organic microfossils as a function of their diagenetic history. Synchrotron-based XANES data collected in situ on individual microfossils, at the submicrometre scale, are compared with data collected on modern microorganisms. Despite diagenetic temperatures of ~150–170 °C deduced from Raman data, the molecular signatures of some Gunflint organic microfossils have been exceptionally well preserved. Remarkably, amide groups derived from protein compounds can still be detected.

The scientists collected samples from about 7 locations. Using models of metamorphic temperatures during diagenesis (rock formation), they show that slightly higher temperatures in some regions erased the signature of protein compounds. Yet as they say, “remarkably” some protein compounds survived temperatures up to 338° F.

They repeatedly say that the spectra show exceptional preservation when compared to modern microbes:

Taking advantage of the unique capabilities of STXM-based XANES spectroscopy at the carbon and nitrogen K edges to perform in situ experiments at the submicrometre scale, the present study shows that, in addition to the fine-scale morphologies, the molecular biosignatures of some Gunflint organic microfossils have been exceptionally preserved. In fact, despite the 1.88-Gyr-long geological history that they experienced, Kakabeka Falls and Schreiber Beach organic microfossils exhibit C- and N-XANES spectra sharing strong similarities to those of modern cyanobacteria and modern micro-algae. Despite a higher content of aromatic compounds compared to modern microorganisms, these microfossils exhibit a quite high content of oxygen-based functional groups (carbonyl, phenolic, carboxylic and hydroxyl groups). In addition, these microfossils still contain amide functional groups (absorption feature at 288.2 eV), which were likely to be involved in the proteinaceous compounds synthetized by the once living organisms.

One hears an echo of astonishment at the similarities “despite” a presumed time gap of nearly two billion years and the presence of oxygen, which should have accelerated destruction of the biomolecules.

Ancient DNA Studies on a Roll

No DNA is preserved in the Gunflint cherts, but the ability to find and read DNA sequences from fossils in other strata has led to a scientific revolution (6/16/16). Science Daily says that ancient DNA has become a “Rosetta Stone” for studies of human impacts on Ice Age megafauna, for instance. Ann Gibbons at Science Magazine regrets that US scientists are behind the Europeans in reaping the harvest of ancient DNA for studies of human evolution. It wasn’t that long ago that scientists didn’t believe DNA could survive more than a few decades or centuries. Now, they’re finding it all over.

It stretches credibility to believe that delicate side chains of proteins could survive “despite the 1.88-Gyr [billion year]-long geological history that they experience.” Maybe they didn’t experience it. Anybody think of that?

Unless we crack the hardened, fossilized stone of geologic time, Darwinism will likely survive. Time is the Darwinians’ closet in which they hide their skeletons; given enough time, they think, anything can happen—even Stuff. Clean house and shine light on that secret chamber, and the whole Darwin enterprise would be exposed for the hoax that it is.*

* “Stuff Happens” is not a scientific theory.

 

 

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