Project description:Mycobacterium tuberculosis (MTB) is a species of pathogenic bacteria and the causative agent of tuberculosis. The type strain H37Rv has been sequenced in 1998, while many previous studies found its predicted genes exhibit frequent errors, particularly in start codons. Here, we applied a TMPP [(N-Succinimidyloxycarbonylmethyl) tris (2,4,6-trimethoxyphenyl) phosphonium bromide] labeling combined with StageTip separating strategy to characterize the N-terminal peptides. We identified 2,598 annotated proteins, which 1,078 proteins were labeled by TMPP.
Project description:Comparative genomic hybridizations were performed to compare bont/A1 strains with an A2-like toxin gene cluster organization to the genome sequenced strain, C. botulinum ATCC 3502. Keywords: comparative genomic hybridization
Project description:Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis (MTB), which resulted millions of deaths worldwide every year. Although the type strain M. tuberculosis H37Rv was sequenced in 1998, annotation errors of encoding genes have emerged in an endless stream. The annotation errors are particularly severe in the N-terminal and start sites of the genes. In this study, we applied a dimethylation labeling combined with negative enrichment strategy on M. tuberculosis H37Rv to characterize the N-terminal start sites of its annotated encoding genes. Totally, 18,285 peptides and 1,641 N-terminal peptides were identified from all the 2,728 database annotated proteins. The negative N-terminal enrichment strategy allowed the re-annotation of 12 genes’ N-terminal and identification of 6 novel genes in H37Rv. The comparative genomics approach could provide possible help for the re-annotation of 403 mis-annotated genes from Mycobacteriaceae. In addition, we verified the novel gene Rv3409, which was identified with 3 high-confident peptides, with the synthetic peptides and the expression of recombinant protein Rv3409. Altogether, our study and findings contributed to a better understanding of the N-terminal annotation of H37Rv, which will contribute to further biological studies of other species of Mycobacteriaceae in the future.
