title: DNA Replication in Mycobacterium tuberculosis.
abstract: Faithful replication and maintenance of the genome are essential to the ability of any organism to survive and propagate. For an obligate pathogen such as Mycobacterium tuberculosis that has to complete successive cycles of transmission, infection, and disease in order to retain a foothold in the human population, this requires that genome replication and maintenance must be accomplished under the metabolic, immune, and antibiotic stresses encountered during passage through variable host environments. Comparative genomic analyses have established that chromosomal mutations enable M. tuberculosis to adapt to these stresses: the emergence of drug-resistant isolates provides direct evidence of this capacity, so too the well-documented genetic diversity among M. tuberculosis lineages across geographic loci, as well as the microvariation within individual patients that is increasingly observed as whole-genome sequencing methodologies are applied to clinical samples and tuberculosis (TB) disease models. However, the precise mutagenic mechanisms responsible for M. tuberculosis evolution and adaptation are poorly understood. Here, we summarize current knowledge of the machinery responsible for DNA replication in M. tuberculosis, and discuss the potential contribution of the expanded complement of mycobacterial DNA polymerases to mutagenesis. We also consider briefly the possible role of DNA replication-in particular, its regulation and coordination with cell division-in the ability of M. tuberculosis to withstand antibacterial stresses, including host immune effectors and antibiotics, through the generation at the population level of a tolerant state, or through the formation of a subpopulation of persister bacilli-both of which might be relevant to the emergence and fixation of genetic drug resistance.
authors.affiliation: Centre for HIV and STIs, National Institute for Communicable Diseases of the National Health Laboratory Service, Johannesburg, 2131, South Africa.
authors.forename: Zanele
authors.initials: Z
authors.lastname: Ditse
authors.affiliation: Medical Research Council Laboratory of Molecular Biology, Cambridge, CB2 0QH United Kingdom.
authors.forename: Meindert H
authors.initials: MH
authors.lastname: Lamers
authors.affiliation: South African Medical Research Council (SAMRC)/National Health Laboratory Services (NHLS)/University of Cape Town (UCT) Molecular Mycobacteriology Research Unit, Department of Science and Technology (DST)/National Research Foundation (NRF) Centre of Excellence for Biomedical TB Research, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Rondebosch 7700, South Africa.|Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town; Rondebosch 7700 South Africa.
authors.forename: Digby F
authors.initials: DF
authors.lastname: Warner
mesh_terms: D000220:Adaptation, Biological; D000818:Animals; D004261:DNA Replication; D006801:Humans; D009154:Mutation; D009169:Mycobacterium tuberculosis / Q000235:genetics* / Q000254:growth & development*