What is the Difference Between Mycobacterium Tuberculosis and Mycobacterium Leprae

The key difference between Mycobacterium tuberculosis and Mycobacterium leprae is that Mycobacterium tuberculosis is the causative agent of tuberculosis while Mycobacterium leprae is the causative agent of Hansen’s disease (leprosy).

The family Mycobacteriaceae comprises a single genus known as Mycobacterium with over 190 species. The bacterial family includes pathogenic species such as Mycobacterium tuberculosis, Mycobacterium leprae, and Mycobacterium abscessus, as well as non-pathogenic species such as Mycobacterium smegmatis and Mycobacterium thermoresistibile. Mycobacterium tuberculosis and Mycobacterium leprae are two pathogenic species belonging to Mycobacteriaceae.

CONTENTS

1. Overview and Key Difference
2. What is Mycobacterium Tuberculosis 
3. What is Mycobacterium Leprae
4. Similarities – Mycobacterium Tuberculosis and Mycobacterium Leprae
5. Mycobacterium Tuberculosis vs Mycobacterium Leprae in Tabular Form
6. Summary – Mycobacterium Tuberculosis vs Mycobacterium Leprae

What is Mycobacterium Tuberculosis?

Mycobacterium tuberculosis is a species of pathogenic bacteria that belongs to the family Mycobacteriaceae. This species is the causative agent of tuberculosis. It was first discovered in 1882 by Robert Koch. M. tuberculosis has an unusual waxy coating on its cell surface due to the presence of mycolic acid. This waxy coating makes the cells impervious to Gram staining. Because of this, M. tuberculosis appears weakly gram-positive. Moreover, acid-fast stains such as Ziel-Neelsen or fluorescent stains such as auramine are frequently used to identify M. tuberculosis. The genome of this bacterium was first sequenced in 1998 by using the strain H37Rv. The genome of this species is 4,411,532 base pairs (4.4 Million base pairs) in size with 3993 genes.

M. tuberculosis is highly aerobic and requires high levels of oxygen. It is primarily a pathogen of the mammalian respiratory system. It infects the lungs. M. tuberculosis species can be diagnosed through tuberculin skin test, acid-fast stain, cultures, and polymerase chain reaction. Furthermore, the BCG vaccine that was derived from Mycobacterium bovis is effective against childhood and severe forms of tuberculosis. However, this vaccine has limited success in preventing the most common form of tuberculosis disease, adult pulmonary tuberculosis.

What is Mycobacterium Leprae?

Mycobacterium leprae is a species in the family of Mycobacteriaceae, which is the causative agent of Hansen’s disease (leprosy). It is a chronic infectious disease that damages the peripheral nerves, which targets the skin, eyes, nose, and muscles. This bacterial species is also known as leprosy bacillus or Hansen’s bacillus. This disease was discovered by the Norwegian physician Gerhard Armauer Hansen in 1873 while he was searching for the bacteria in the skin nodules of patients with leprosy. Leprosy can occur at all stages, from infancy to adulthood.

Diagnosis of M. leprae can be made through physical examinations, skin biopsy, and cultures. The treatment options for this infection include rifampicin and clofazimin. Moreover, this was the first bacterium to be identified as the causative agent of disease in humans. Furthermore, the genome size of this species is 3,268 203 base pairs with 1614 genes.

What are the Similarities Between Mycobacterium Tuberculosis and Mycobacterium Leprae?

• tuberculosis and M. leprae are two pathogenic species that belong to the family Mycobacteriaceae.
• They are gram-positive.
• Both species are acid-fast intracellular pathogens.
• Their genomes were first sequenced in 1998.

What is the Difference Between Mycobacterium Tuberculosis and Mycobacterium Leprae?

M. tuberculosis is the causative agent of tuberculosis, while M. leprae is the causative agent of Hansen’s disease (leprosy). Thus, this is the key difference between Mycobacterium tuberculosis and Mycobacterium leprae. Furthermore, the genome size of M. tuberculosis is 4,411,532 base pairs, while the genome size of M. leprae is 3,268,203 base pairs.

The below infographic presents the differences between Mycobacterium tuberculosis and Mycobacterium leprae in tabular form for side-by-side comparison.

Summary – Mycobacterium Tuberculosis vs Mycobacterium Leprae

Mycobacterium tuberculosis and Mycobacterium leprae are two pathogenic species categorized under the genus Mycobacterium, which belongs to the family Mycobacteriaceae. M. tuberculosis causes tuberculosis, while M. leprae causes Hansen’s disease (leprosy). So, this is the summary of the difference between Mycobacterium tuberculosis and Mycobacterium leprae.

Reference:

1. “Tuberculosis.” Mayo Clinic, Mayo Foundation for Medical Education and Research.
2. “Mycobacterium Leprae.” An Overview | ScienceDirect Topics.

Image Courtesy:

1. “Mycobacterium tuberculosis Bacteria, the Cause of TB” By NIAID (CC BY 2.0) via Flickr
2.”Mycobacterium leprae in Magnification of 2000X” By Ajay Kumar Chaurasiya – Own work (CC BY-SA 4.0) via Commons Wikimedia