The evolution of metabolic enzymes in Plasmodium and trypanosomatids as compared to Saccharomyces and Schizosaccharomyces

详细信息	查看全文 | 推荐本文 |

• 作者：Peter M. Palenchar ; ^{peter.palenchar@villanova.edu} ; ^{ppalenchar@gmail.com} ; Jennifer B. Palenchar¹ ; ^{jennifer.palenchar@villanova.edu}
• 关键词：Ka ; number of non-synonymous substitutions per non-synonymous site ; Ks ; the number of synonymous substitutions per synonymous site ; BLAST ; Basic Local Alignment Search Tool ; KEGG ; Kyoto Encyclopedia of Genes and Genomes ; NTP ; Nucleotide triphosphate ; NMP
• 刊名：Molecular and Biochemical Parasitology
• 出版年：2012
• 期刊代码：108_01666851
• 类别：bio
• 出版时间：July, 2012
• 卷：184
• 期：1
• 页码：13-19
• 文件大小：392 K

摘要

Understanding how the biological connectivity of genes and gene products affects evolution is an important aspect of understanding evolution. Genes encoding enzymes are frequently used to carry out such analyses. Interestingly, studies have shown that connectivity in the metabolic networks in parasitic protists, including Plasmodium falciparum and Trypanosoma brucei, have been substantially altered as compared to free living eukaryotes, such as Saccharomyces cerevisiae. Herein, we have determined K_a values, which are a measure of the non-synonymous substitution rate, and used them to examine the differences between the evolution of genes in T. brucei, P. falciparum, S. cerevisiae, and Schizosaccharomyces pombe. All four organisms share similar traits with respect to the evolution of genes encoding metabolic enzymes. First, genes encoding metabolic enzymes have lower K_a values than genes encoding non-metabolic proteins. In addition, perturbations of the metabolic network appear to have limited affects on the genes encoding enzymes near the perturbation. In most cases, there is a negative relationship between connectivity in the metabolic network of the gene product and the K_a value for the gene, i.e. examining how much constraint there is on gene evolution when it is connected to many other genes. In addition, we find that the K_a values of orthologs encoding for metabolic enzymes in each organism are significantly correlated, indicating similar patterns of non-synonymous substitutions. In total, our results indicate that the evolution of genes encoding metabolic enzymes do not tend to be greatly affected by changes in the metabolic network.