Ancient Origin and Gene Mosaicism of the Progenitor of Mycobacterium tuberculosis

By M. Gutierrez, S. Brisse, R. Brosch, M. Fabre, Bahia Omaïs, M. Marmiesse, P. Supply, V. Vincent. PLoS Pathogens, 2005

664 citations recorded by the source corpus.

The highly successful human pathogen Mycobacterium tuberculosis has an extremely low level of genetic variation, which suggests that the entire population resulted from clonal expansion following an evolutionary bottleneck around 35,000 y ago. Here, we show that this population constitutes just the visible tip of a much broader progenitor species, whose extant representatives are human isolates of tubercle bacilli from East Africa. In these isolates, we detected incongruence among gene phylogenies as well as mosaic gene sequences, whose individual elements are retrieved in classical M. tuberculosis. Therefore, despite its apparent homogeneity, the M. tuberculosis genome appears to be a composite assembly resulting from horizontal gene transfer events predating clonal expansion. The amount of synonymous nucleotide variation in housekeeping genes suggests that tubercle bacilli were contemporaneous with early hominids in East Africa, and have thus been coevolving with their human host much longer than previously thought. These results open novel perspectives for unraveling the molecular bases of M. tuberculosis evolutionary success.

Subfields: Epidemiology, Genetics, Infectious Diseases

View Paper: https://www.semanticscholar.org/paper/a319a44888e45b7662a14a46d6a8d31bae670523

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Epidemiology

1. Stefan Niemann
2. D. Russell

In Genetics

1. Stefan Niemann
2. Peter M. Small
3. Michal Feldman
4. K. Kremer
5. S. Gagneux
6. Mikhail Lipatov

In Infectious Diseases

1. Stefan Niemann
2. D. Russell
3. Michal Feldman

Citations in the corpus

• Proposal for Standardization of Optimized Mycobacterial Interspersed Repetitive Unit-Variable-Number Tandem Repeat Typing of Mycobacterium tuberculosis (2006, background): “Because of their particular population structure, characterized by homogeneous clonal groups with horizontal gene transfers among them (15), M.”
• Genomic islands: tools of bacterial horizontal gene transfer and evolution (2008, background): “that were initially environmental bacteria occurred only relatively recently, about a million years ago, and are linked to the invasion of the genome by foreign DNA (Gutierrez et al., 2005; Rosas-Magallanes et al., 2006; Becq et al., 2007).”
• Who puts the tubercle in tuberculosis? (2007, background): “bovis , or the two strains evolved in parallel from a founder strain that infected both humans and cattl”
• Human T cell epitopes of Mycobacterium tuberculosis are evolutionarily hyperconserved (2010, neutral): “…of T cell antigens in MTBC, we used Illumina next-generation DNA sequencing to generate nearly complete genome sequences from 20 strains representative of the six main human MTBC lineages, and one strain of Mycobacterium canettii which is the closest known outgroup of MTBC 3 , 22 (Table 1).”
• High Functional Diversity in Mycobacterium tuberculosis Driven by Genetic Drift and Human Demography (2008, background): “Specifically, most evidence indicates that MTBC originated in Africa.”