Related Experiment Video
Updated: Aug 4, 2025
08:21
Curation of Computational Chemical Libraries Demonstrated with Alpha-Amino Acids
Published on: April 13, 2022
2.7K
What Would an Alien Amino Acid Alphabet Look Like and Why?
Sean M Brown1, Václav Voráček2, Stephen Freeland1
1Department of Biological Sciences, University of Maryland, Baltimore County, Maryland, USA.
Astrobiology
|April 6, 2023
Summary
Life uses 20 specific L-α-amino acids due to their unique biophysical properties. Researchers explored alternative amino acid sets, finding some predisposed to forming life-like alphabets, but many possibilities remain for alien biochemistry.
Area of Science:
- Biochemistry
- Astrobiology
- Evolutionary Biology
Background:
- Life on Earth utilizes a core set of 20 L-α-amino acids for protein synthesis.
- Numerous other amino acids were available during early life's evolution.
- The specific properties of life's amino acid alphabet are not fully understood.
Purpose of the Study:
- To investigate the reasons behind the selection of Earth's 20 L-α-amino acids.
- To identify alternative amino acid sets that could support life's functions.
- To explore the vast chemical space of potential amino acid alphabets.
Main Methods:
- Utilized a heuristic search algorithm to explore a library of plausible alternative amino acids.
- Analyzed the biophysical properties of different amino acid sets.
- Examined the impact of various assumptions on alphabet selection.
Main Results:
- Identified a subset of amino acids predisposed to forming life-like alphabets.
- Demonstrated that fundamental biophysics significantly reduces, but does not eliminate, possibilities for amino acid alphabets.
- Highlighted a remaining vast number of potential alphabets (10^45).
Conclusions:
- The selection of Earth's amino acid alphabet is influenced by biophysical properties, but other factors likely played a role.
- Further research into alphabet construction is needed to understand the constraints on alien biochemistry.
- This work provides a framework for predicting potential alien amino acid alphabets.
Keywords:
AbiogenesisAmino acidComputational biochemistry. Astrobiology 23, 536–549EvolutionMolecular biochemistryXenobiologyMore Related Videos
08:14Extraction of Non-Protein Amino Acids from Cyanobacteria for Liquid Chromatography-Tandem Mass Spectrometry Analysis
Published on: December 9, 2022
3.8K
11:47Residue-specific Incorporation of Noncanonical Amino Acids into Model Proteins Using an Escherichia coli Cell-free Transcription-translation System
Published on: August 1, 2016
16.0K
Related Concept Videos
03:42Amino acids
89.4K
Amino acids are the monomers that comprise proteins. Each amino acid has the same fundamental structure, which consists of a central carbon atom, or the alpha (α) carbon, bonded to an amino group (NH2), a carboxyl group (COOH), and to a hydrogen atom. Every amino acid also has another atom or group of atoms bonded to the central atom known as the R group. There are 20 common amino acids present in proteins, each with a different R group. Variation in the amino acid sequence is responsible...
89.4K
03:06From DNA to Protein
18.6K
The flow of genetic information in cells from DNA to mRNA to protein is described by the central dogma, which states that genes specify the sequence of mRNAs, which in turn specify the sequence of amino acids making up all proteins. The decoding of one molecule to another is performed by specific proteins and RNAs. Because the information stored in DNA is so central to cellular function, it makes intuitive sense that the cell would make mRNA copies of this information for protein synthesis...
18.6K
02:26tRNA Activation
19.5K
Aminoacyl-tRNA synthetases are present in both eukaryotes and bacteria. Though eukaryotes have 20 different aminoacyl-tRNA synthetases to couple to 20 amino acids, many bacteria do not have genes for all of these aminoacyl-tRNA synthetases. Despite this, they still use all 20 amino acids to synthesize their proteins. For instance, some bacteria do not have the gene encoding the enzyme that couples glutamine with its partner tRNA. In these organisms, one enzyme adds glutamic acid to all of the...
19.5K
01:25The Central Dogma
127.3K
Overview
127.3K
01:29Amino Acid Biosynthetic Pathways
55
Amino acid biosynthesis is essential for cell growth, protein synthesis, and metabolic regulation. Cells generate essential and non-essential amino acids from metabolic intermediates to sustain vital biological functions. These intermediates originate from key metabolic pathways: glycolysis, the tricarboxylic acid (TCA) cycle, and the pentose phosphate pathway. Important precursors include α-ketoglutarate, pyruvate, oxaloacetate, phosphoenolpyruvate, and erythrose-4-phosphate, which...
55
02:28Leaky Scanning
5.2K
During most eukaryotic translation processes, the small 40S ribosome subunit scans an mRNA from its 5' end until it encounters the first start AUG codon. The large 60S ribosomal subunit then joins the smaller one to initiate protein synthesis. The location of the translation initiation is largely determined by the nucleotides near the start codon as there may be multiple translation initiation sites present on the mRNA. Marilyn Kozak discovered that the sequence RCCAUGG (where R...
5.2K