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Amino acid composition
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The ''amino acid composition'' of a protein refers to the percentages of each amino acid in the sequence of that protein. The percentage, sometimes called the Mole percentage, is calculated as the number of a given amino acid divided by the total number of amino acids in the protein chain or molecule. | The ''amino acid composition'' of a protein refers to the percentages of each amino acid in the sequence of that protein. The percentage, sometimes called the Mole percentage, is calculated as the number of a given amino acid divided by the total number of amino acids in the protein chain or molecule. | ||
| - | + | '''GC-content''' of the organism's genome is the strongest genome-level determinant of amino acid composition.<ref name="tekala-genomes">PMID: 12384285</ref>. | |
Other, weaker influences are: | Other, weaker influences are: | ||
Revision as of 23:31, 23 April 2020
The amino acid composition of a protein refers to the percentages of each amino acid in the sequence of that protein. The percentage, sometimes called the Mole percentage, is calculated as the number of a given amino acid divided by the total number of amino acids in the protein chain or molecule.
GC-content of the organism's genome is the strongest genome-level determinant of amino acid composition.[1].
Other, weaker influences are:
- Growth temperatures (mesophily/thermophily/hyperthermophily). Thermophiles have more glutamic acid (with reduction in glutamine), and more lysine and arginine[1]. This likely relates to the larger number of salt bridges in proteins of thermophiles, believe to contribute to thermostability.
- Chain length.
Proteins of thermophiles are, on average, shorter than those of mesophiles. Average lengths are 283 and 340, respectively[1].
References
- ↑ 1.0 1.1 1.2 Tekaia F, Yeramian E, Dujon B. Amino acid composition of genomes, lifestyles of organisms, and evolutionary trends: a global picture with correspondence analysis. Gene. 2002 Sep 4;297(1-2):51-60. doi: 10.1016/s0378-1119(02)00871-5. PMID:12384285 doi:http://dx.doi.org/10.1016/s0378-1119(02)00871-5
