Mycobacterium thermoresistibile

Mycobacterium thermoresistibile is a species of bacteria in the genus Mycobacterium. It is a non-tuberculous mycobacterium (NTM) that is known for its ability to withstand high temperatures, which is reflected in its name. This species is of interest in both clinical and environmental microbiology due to its unique characteristics and potential implications for human health.

Characteristics

Mycobacterium thermoresistibile is a Gram-positive bacterium, although it does not retain the crystal violet stain used in the Gram staining method due to its high mycolic acid content. It is an acid-fast organism, which means it retains certain dyes after being washed with acidic solutions. This property is used in the Ziehl-Neelsen stain to identify mycobacteria.

Morphology

The cells of M. thermoresistibile are rod-shaped and can form filamentous structures. They are aerobic, requiring oxygen for growth, and are non-motile. The cell wall is rich in lipids, contributing to its resistance to chemical damage and dehydration.

Growth and Culture

M. thermoresistibile grows optimally at temperatures between 45°C and 55°C, which is higher than most other mycobacteria. It can be cultured on standard mycobacterial media such as Lowenstein-Jensen medium and Middlebrook 7H10 agar. Colonies are typically smooth and non-pigmented.

Pathogenicity

While M. thermoresistibile is not a major human pathogen, it has been isolated from clinical specimens, indicating its potential to cause disease under certain conditions. It is considered an opportunistic pathogen, primarily affecting individuals with compromised immune systems.

Clinical Manifestations

Infections with M. thermoresistibile can manifest as pulmonary disease, similar to other non-tuberculous mycobacterial infections. Symptoms may include chronic cough, fever, and weight loss. It can also cause skin and soft tissue infections following trauma or surgical procedures.

Diagnosis

Diagnosis of M. thermoresistibile infection involves the isolation and identification of the organism from clinical specimens. Acid-fast bacilli (AFB) staining and culture are primary methods. Molecular techniques such as polymerase chain reaction (PCR) and 16S rRNA sequencing can provide definitive identification.

Treatment

Treatment of infections caused by M. thermoresistibile is challenging due to its intrinsic resistance to many common antibiotics. Antimicrobial susceptibility testing is essential to guide therapy. Treatment regimens may include a combination of macrolides, rifamycins, and other agents effective against mycobacteria.

Environmental Occurrence

M. thermoresistibile is found in a variety of environmental settings, including soil and water. Its ability to survive at elevated temperatures suggests it may inhabit thermal environments such as hot springs.

Research and Applications

Research on M. thermoresistibile focuses on understanding its thermal resistance mechanisms and potential applications in biotechnology. Its enzymes, stable at high temperatures, may have industrial applications.

See also

• Mycobacterium
• Non-tuberculous mycobacteria
• Acid-fast bacteria