Amino acid cost and codon-usage biases in 6 prokaryotic genomes: A whole-genome analysis
Amino acid cost and codon-usage biases in 6 prokaryotic genomes: A whole-genome analysis
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DOI：
10.1093/molbev/msl029
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发表时间：
2006-09-01
影响因子：
10.7
通讯作者：
Krane, Dan E.
中科院分区：
文献类型：
--
作者：
Heizer, Esley M., Jr.;Raiford, Douglas W.;Krane, Dan E.
对于大多数原核生物，氨基酸生物合成代表了其总能量预算的重要部分。氨基酸之间合成成本的差异可能是惊人的，差异高达7倍。两种原核生物，大肠杆菌和枯草芽孢杆菌，已被证明优先利用高表达基因中成本较低的氨基酸，表明氨基酸选择中的简约性可能赋予原核生物选择优势。本研究证实了这些发现，并将其扩展到另外4种原核生物：沙眼衣原体、肺炎衣原体AR 39、集胞藻属PCC 6803和嗜热栖热菌HB 27。这6种生物体中的每一种对密码子使用偏差的坚持与编码区的平均氨基酸生物合成成本呈负相关，其方式独立于化能异养、光合自养或嗜热生活方式。专性寄生虫C.沙眼衣原体和沙眼衣原体。肺炎链球菌AR 39不能合成20种常见氨基酸中的许多种。在这些生物体中去除营养缺陷型氨基酸并不改变在高表达基因中优先使用能量便宜的氨基酸的总体趋势。
For most prokaryotic organisms, amino acid biosynthesis represents a significant portion of their overall energy budget. The difference in the cost of synthesis between amino acids can be striking, differing by as much as 7-fold. Two prokaryotic organisms, Escherichia coli and Bacillus subtilis, have been shown to preferentially utilize less costly amino acids in highly expressed genes, indicating that parsimony in amino acid selection may confer a selective advantage for prokaryotes. This study confirms those findings and extends them to 4 additional prokaryotic organisms: Chlamydia trachomatis, Chlamydophila pneumoniae AR39, Synechocystis sp. PCC 6803, and Thermus thermophilus HB27. Adherence to codon-usage biases for each of these 6 organisms is inversely correlated with a coding region's average amino acid biosynthetic cost in a fashion that is independent of chemoheterotrophic, photoautotrophic, or thermophilic lifestyle. The obligate parasites C. trachomatis and C. pneumoniae AR39 are incapable of synthesizing many of the 20 common amino acids. Removing auxotrophic amino acids from consideration in these organisms does not alter the overall trend of preferential use of energetically inexpensive amino acids in highly expressed genes.