What is H37Ra?
What is H37Ra?
The attenuated Mycobacterium tuberculosis strain H37Ra is one of the most commonly used controls for M. tuberculosis identification in the clinical laboratory and is a source of false-positive results for M. tuberculosis as a consequence of cross-contamination.
How many chromosomes does Mycobacterium tuberculosis have?
The M. tuberculosis Erdman genome consists of a single circular chromosome of 4,392,353 bp, with an average GC content of 65.6%. The chromosome was shown to contain a total of 4,246 protein-coding genes, 52 tRNA genes, one transfer mRNA for all amino acids, and 1 rrn operon.
What is tb genome?
TB genotyping is a laboratory-based approach used to analyze the genetic material (e.g., DNA) of Mycobacterium tuberculosis, the bacterium that causes TB disease. The total genetic content is referred to as the genome.
What is H37Rv strain?
Mycobacterium tuberculosis strain H37Rv is the most studied strain of tuberculosis in research laboratories. It was first isolated by Dr. Edward R. Baldwin in 1905. The strain came from a 19 year old patient with chronic pulmonary tuberculosis at the Trudeau Sanatorium in Saranac Lake, New York.
How does Mycobacterium tuberculosis affect the body?
The general symptoms of TB disease include feelings of sickness or weakness, weight loss, fever, and night sweats. The symptoms of TB disease of the lungs also include coughing, chest pain, and the coughing up of blood. Symptoms of TB disease in other parts of the body depend on the area affected.
Does TB have DNA?
tuberculosis is a clonal organism and does not exchange DNA via horizontal gene transfer. This, possibly combined with a relatively low rate of evolution, might explain why the evolution of resistance has been relatively slow in the species compared to some other major bacterial pathogens.
Why do tuberculosis bacteria live in human lungs?
When they breathe in the bacterium, it settles in their lungs and starts growing because their immune systems cannot fight the infection. In these instances, TB disease may develop within days or weeks after the infection.
What was the genomic analysis of Mycobacterium tuberculosis?
Finally, we conducted a comparative genomics analysis of the five newly assembled genomes, H37Rv and KZN605 to detect the genetic changes such as gene gains/losses, insertions and deletions (indels), and translocations among these genomes.
Is the H37Rv genome a standard reference genome?
The H37Rv genome has been used as a standard reference genome for detecting mutations. However, it is Euro-American, so it is not closely related to Beijing lineage isolates and may miss many genes that are Beijing lineage-specific. It is therefore desirable to construct a Beijing lineage reference.
Where can I find Mycobacterium tuberculosis isolates?
To identify DR mutations, we analyzed the genomes of six Beijing lineage M. tuberculosis isolates and one Euro-American lineage isolate collected in Taiwan with different DR profiles. These isolates were deposited at the Taiwan Centers for Disease Control (TCDC) and are here named as TCDC1, TCDC3, TCDC4, TCDC5, TCDC7, TCDC10, and TCDC11.
Which is the avirulent phenotype of M.tuberculosis?
The genetic basis for the avirulent phenotype of M. tuberculosis H37Ra in animal models is not known. Since the H37Ra strain does not revert to a virulent phenotype on passaging through animals, it is likely that the former has acquired multiple point mutations or small deletions/rearrangements in genes crucial for virulence.