Interaction analysis of Mycobacterium tuberculosis between the host environment and highly mutated genes from population genetic structure comparison

Towards the reconstruction of a global TB history using a new pipeline "TB-Annotator"

Mycobacterium tuberculosis complex (MTBC) has a population structure consisting of 9 human and animal lineages. The genomic diversity within these lineages is a pathogenesis factor that affects virulence, transmissibility, host response, and antibiotic resistance. Hence it is important to develop improved information systems for tracking and understanding the spreading and evolution of genomes. We present results obtained thanks to a new informatics platform for computational biology of MTBC, that uses a convenience sample from public/private SRAs, designated as TB-Annotator. Version 1 was a first interactive graphic-based web tool based on 15,901 representative genomes. Version 2, still interactive, is a more sophisticated database, developed using the Snakemake Workflow Management System (WMS) that allows an unsupervised global and scalable analysis of the content of the USA National Center for Biotechnology Information Short Read Archives database. This platform analyzes nucleotide variants, the presence/absence of genes, known regions of difference and detect new deletions, the insertion sites of mobile genetic elements, and allows phylogenetic trees to be built, imported in a graphical interface and interactively analyzed between the data and the tree. The objective of TB-Annotator is triple: detect recent epidemiological links, reconstruct distant phylogeographical histories as well as perform more complex phenotypic/genotypic Genome-Wide Association Studies (GWAS). In this paper, we compare the various taxonomic SNPs-based labels and hierarchies previously described in recent reference papers for L1, and present a comparative analysis that allows identification of alias and thus provides the basis of a future unifying naming scheme for L1 sublineages. We present a global phylogenetic tree built with RAxML-NG, and one on L2; at the time of writing, we characterized about 200 sublineages, with many new ones; a detail tree for Modern L2 and a hierarchical scheme allowing to facilitate L2 lineage assignment are also presented.

Multiple CD59 Polymorphisms in Chinese Patients with Mycobacterium tuberculosis Infection

Background and Objective. Tuberculosis (TB) is a major threat to human health, especially in developing countries. Its susceptibility and progression depend on interactions between mycobacterium tuberculosis, host immune system, and genetic and environmental factors. Up to now, many studies have presented the association between TB susceptibility and host genetic polymorphisms, but never regarding CD59 gene, which is an essential complement regulator. This study investigated the relationship between multiple CD59 single nucleotide polymorphisms (SNPs) and susceptibility to TB among Chinese patients. Methods. A case–control study was conducted to investigate the SNPs at CD59 rs1047581, rs7046, rs2231460, rs184251026, rs41275164, rs831633, rs704700, rs41275166, and rs10768024 by sequence-specific primer-polymerase chain reaction (SSP-PCR) in 900 tuberculosis patients and 1,534 controls. Results. The minor allele frequencies at rs2231460, rs184251026, rs41275164, and rs41275166 were extremely low both in the Cases (0.00%–0.61%) and in the Controls (0.07%–0.43%), comparatively at rs1047581, rs7046, rs831633, rs704700, and rs10768024 were notably higher both in the Cases (8.23%–48.39%) and in the Controls (8.57%–47.16%). Among the nine SNPs, only homozygous CC genotype at rs10768024 showed a significant protective effect against TB than homozygous TT genotype (OR(95% CI) = 0.59(0.38, 0.91), χ2 = 5.779, $P=0.016$ ), and homozygous TT and heterozygous CT genotypes showed a significant risk of TB infection in the recessive model (OR(95% CI) = 1.68(1.10, 2.56), χ2 = 5.769, $P=0.016$ ). Further analysis verified that rs10768024 CC genotype independently related to TB susceptibility (OR(95% CI) = 0.60(0.39, 0.91), Wald χ2 = 5.664, $P=0.017$ ) in multivariate logistic regression analysis, and its genetic mutation was independent of the other SNPs (r2 = 0.00–0.20) in haplotype analysis. Conclusions. The first investigation of the CD59 gene and susceptibility to TB suggests a significant risk with homozygous TT and heterozygous CT genotypes at rs10768024 loci. The homozygous CC mutation at rs10768024 loci showed a significant protection against TB susceptibility.

A review on enzyme complexes of electron transport chain from Mycobacterium tuberculosis as promising drug targets

Energy metabolism is a universal process occurring in all life forms. In Mycobacterium tuberculosis (Mtb), energy production is carried out in two possible ways, oxidative phosphorylation (OxPhos) and substrate-level phosphorylation. Mtb is an obligate aerobic bacterium, making it dependent on OxPhos for ATP synthesis and growth. Mtb inhabits varied micro-niches during the infection cycle, outside and within the host cells, which alters its primary metabolic pathways during the pathogenesis. In this review, we discuss cellular respiration in the context of the mechanism and structural importance of the proteins and enzyme complexes involved. These protein-protein complexes have been proven to be essential for Mtb virulence as they aid the bacteria's survival during aerobic and hypoxic conditions. ATP synthase, a crucial component of the electron transport chain, has been in the limelight, as a prominent drug target against tuberculosis. Likewise, in this review, we have explored other protein-protein complexes of the OxPhos pathway, their functional essentiality, and their mechanism in Mtb's diverse lifecycle. The review summarises crucial target proteins and reported inhibitors of the electron transport chain pathway of Mtb.