Improvements in amino acid assembly imaging can help understand life formation
DOI: 10.1063/1.5135315
Improvements in amino acid assembly imaging can help understand life formation lead image
The study of amino acid assembly is important to the understanding of the origin of life on Earth. However, scanning tunneling microscopy techniques typically take place in an ultra-high vacuum and low temperature regime, which is unrealistic compared to real life environments. In a new paper, Phillips et al. fill the gap by studying amino acid assembly in ambient conditions.
“The purpose of this experiment was to provide data that can be used to bridge surface studies taken under pristine conditions at ultra-high vacuum and low temperature to more biologically relatable studies of the same systems,” said author Erin Iski. “We rarely see a pristine condition in biology, and it is important to know how these studies change when taken to more realistic scenarios.”
By using electrochemical scanning tunneling microscopy, the researchers were able to image amino acid island growth on gold substrates in biologically relevant regimes. Five different amino acids with different structures were used in the study.
During the experiment, all five amino acids trapped diffusing gold atoms at the surface of the substrate to form islands, making the experiment the first in situ demonstration of island formation. The islands were similar to those formed in ultra-high vacuum, low temperature environments. As amino acid islands grow, they combine into more complex structures, like protein and DNA.
“Understanding the role of surfaces and the associated amino acid interactions at biologically relevant conditions is key to understanding possible routes to the formation of life on this planet,” Iski said.
This work confirms that previous results taken under ultra-high vacuum and low temperature may be valid in life-forming environments.
Source: “Using EC-STM to obtain an understanding of amino acid adsorption on Au(111),” by Jesse A. Phillips, K. P. Boyd, I. Baljak, L. K. Harville, and Erin V. Iski, AIP Advances (2019). The article can be accessed at https://doi.org/10.1063/1.5116564 .
