Related Experiment Video
Updated: Jan 3, 2026
08:34
Identification of Virulence Markers of Mycobacterium abscessus for Intracellular Replication in Phagocytes
Published on: September 27, 2018
9.0K
Analysing nonsynonymous mutations between two Mycobacterium bovis strains with contrasting pathogenic profiles
Mercedes Bigi1, Cristina Lourdes Vazquez2, Ana Beatriz C Castelão3
1Universidad de Buenos Aires, Facultad de Agronomía, Cátedra de Microbiología Agrícola, INBA-CONICET, Buenos Aires, Argentina.
Veterinary Microbiology
|November 25, 2019
Summary
Two Mycobacterium bovis strains in Argentina show genetic differences impacting virulence. Strain 04-303 is highly lethal, while strain 534 has reduced phthiocerol dimycocerosate synthesis, affecting its survival in bovine macrophages.
Area of Science:
- Veterinary Microbiology
- Infectious Diseases
- Genomics
Background:
- Mycobacterium bovis causes bovine tuberculosis, a significant zoonotic disease with economic impact.
- Two distinct M. bovis strains, 04-303 (wild boar) and 534 (cattle), were isolated in Argentina.
- Previous studies indicated differential virulence, with 04-303 causing 100% mortality in mice versus survival with limited damage for 534.
Purpose of the Study:
- To compare predictive proteins encoded in the genomes of M. bovis strains 04-303 and 534.
- To identify polymorphic proteins and their potential roles in virulence differences between the strains.
- To investigate the impact of genetic variations on phthiocerol dimycocerosate (PDIM) synthesis and bacterial survival.
Main Methods:
- Comparative genomic analysis of M. bovis strains 04-303 and 534.
- Identification and characterization of polymorphic proteins, focusing on virulence factors.
- Experimental investigation of PDIM synthesis and its correlation with bacterial behavior in macrophages.
Main Results:
- 141 polymorphic proteins were identified between the two M. bovis strains.
- Nine virulence proteins were polymorphic in strain 04-303, and five in strain 534.
- Significant polymorphisms in PDIM synthesis/transport proteins were observed, with mutations in strain 534 impacting PDIM levels and macrophage survival.
Conclusions:
- Strain-specific genetic variations, particularly in PDIM-related proteins, contribute to differential virulence of M. bovis.
- Reduced PDIM synthesis in strain 534 correlates with impaired replication and survival in bovine macrophages.
- Understanding these molecular differences is crucial for developing novel vaccines and diagnostics for bovine tuberculosis.
Related Concept Videos
01:29Modern Molecular Taxonomy
523
Advancements in molecular biology have revolutionized the identification and characterization of bacteria, with multiple methods leveraging DNA sequencing for enhanced precision. As sequencing technologies improve and costs decline, these approaches are increasingly used in clinical, environmental, and evolutionary studies.Multilocus Sequence Typing (MLST) examines several housekeeping genes, essential chromosomal genes encoding cellular functions, to distinguish strains. Approximately...
523
01:18Mutations in Microorganisms
455
Mutations are heritable changes in an organism’s genome involving alterations in the base sequence of DNA or RNA. These changes can influence cellular processes and phenotypic traits, potentially transforming the unaltered wild type into a mutant form. Such changes, termed forward mutations, are pivotal in shaping the genetic diversity of organisms.RNA viruses exhibit the highest mutation rates due to the absence of robust proofreading mechanisms during genome replication. In contrast,...
455
01:20Applications of Molecular Taxonomy
450
Molecular taxonomy has revolutionized the understanding and classification of bacteria, providing precise insights into their diversity, evolutionary relationships, and ecological roles. By utilizing molecular techniques such as DNA sequencing and fingerprinting, researchers have made significant strides in various fields related to bacterial studies.Resolving Taxonomic AmbiguitiesMolecular taxonomy has been instrumental in distinguishing closely related bacterial species initially thought to...
450