21075924

not annotated - annotated - LINNAEUS only

argC Orthologs from Rhizobiales show diverse profiles of transcriptional efficiency and functionality in Sinorhizobium meliloti.

Several factors can influence ortholog replacement between closely related species. We evaluated the transcriptional expression and metabolic performance of ortholog substitution complementing a Sinorhizobium meliloti argC mutant with argC from Rhizobiales (Agrobacterium tumefaciens, Rhizobium etli, and Mesorhizobium loti). The argC gene is necessary for the synthesis of arginine, an amino acid that is central to protein and cellular metabolism. Strains were obtained carrying plasmids with argC orthologs expressed under the speB and argC (S. meliloti) and lac (Escherichia coli) promoters. Complementation analysis was assessed by growth, transcriptional activity, enzymatic activity, mRNA levels, specific detection of ArgC proteomic protein, and translational efficiency. The argC orthologs performed differently in each complementation, reflecting the diverse factors influencing gene expression and the ability of the ortholog product to function in a foreign metabolic background. Optimal complementation was directly related to sequence similarity with S. meliloti, and was inversely related to species signature, with M. loti argC showing the poorest performance, followed by R. etli and A. tumefaciens. Different copy numbers of genes and amounts of mRNA and protein were produced, even with genes transcribed from the same promoter, indicating that coding sequences play a role in the transcription and translation processes. These results provide relevant information for further genomic analyses and suggest that orthologous gene substitutions between closely related species are not completely functionally equivalent.



Ann file

T1	Species 105 127	Sinorhizobium meliloti

N1 Reference T1 Taxonomy:382

T2 Species 326 348 Sinorhizobium meliloti

N2 Reference T2 Taxonomy:382

T3 Species 389 414 Agrobacterium tumefaciens

N3 Reference T3 Taxonomy:358

T4 Species 416 430 Rhizobium etli

N4 Reference T4 Taxonomy:29449

T5 Species 436 454 Mesorhizobium loti

N5 Reference T5 Taxonomy:381

T6 Species 676 687 S. meliloti

N6 Reference T6 Taxonomy:382

T7 Species 698 714 Escherichia coli

N7 Reference T7 Taxonomy:562

T8 Species 1196 1207 S. meliloti

N8 Reference T8 Taxonomy:382

T9 Species 1262 1269 M. loti

N9 Reference T9 Taxonomy:381

T10 Species 1320 1327 R. etli

N10 Reference T10 Taxonomy:29449

T11 Species 1332 1346 A. tumefaciens

N11 Reference T11 Taxonomy:358