Department of Biosciences, Piracicaba Dental School, University of Campinas, Campinas, Brazil.
J Mol Evol. 2021 Jun;89(4-5):257-268. doi: 10.1007/s00239-021-10003-7. Epub 2021 Mar 24.
Proteins can evolve by accumulating changes on amino acid sequences. These changes are mainly caused by missense mutations on its DNA coding sequences. Mutations with neutral or positive effects on fitness can be maintained while deleterious mutations tend to be eliminated by natural selection. Amino acid changes are influenced by the biophysical, chemical, and biological properties of amino acids. There is a multiplicity of amino acid properties that can influence the function and expression of proteins. Amino acid properties can be expressed into numerical indexes, which can help to predict functional and structural aspects of proteins and allow statistical inferences of selection pressure on amino acid usage. The accuracy of these analyses may be compromised by the existence of several numerical indexes that measure the same amino acid property, and the lack of objective parameters to determine the most accurate and biologically relevant index. In the present study, the gradient consistency test was used in order to estimate the magnitude of directional selection imparted by amino acid biochemical and biophysical properties on protein evolution.
蛋白质可以通过在氨基酸序列上积累变化来进化。这些变化主要是由其 DNA 编码序列上的错义突变引起的。对适应度有中性或积极影响的突变可以被保留，而有害突变则倾向于被自然选择所消除。氨基酸变化受氨基酸的物理化学和生物学特性的影响。有许多氨基酸特性可以影响蛋白质的功能和表达。氨基酸特性可以用数值指标来表示，这有助于预测蛋白质的功能和结构方面，并允许对氨基酸使用的选择压力进行统计推断。这些分析的准确性可能会受到以下因素的影响：存在多个测量相同氨基酸特性的数值指标，以及缺乏客观参数来确定最准确和最相关的指标。在本研究中，梯度一致性测试被用来估计氨基酸生化和物理特性对蛋白质进化的定向选择的程度。
