Nontuberculous mycobacteria in the environment.

Area of Science:

• Environmental microbiology
• Waterborne pathogens
• Bacterial ecology

Background:

• Nontuberculous mycobacteria (NTM) are ubiquitous in natural soil and water environments.
• NTM are frequently found in distributed drinking water systems, colonizing pipes and biofilms.
• They are not considered contaminants but rather adapted inhabitants of aquatic environments.

Discussion:

• NTM possess unique adaptations favoring survival and persistence in drinking water systems, including disinfectant resistance and ability to grow in oligotrophic and low-oxygen conditions.
• The lipid-rich outer membrane of NTM provides a hydrophobic barrier, hindering disinfectant and antibiotic penetration.
• Biofilm formation on plumbing surfaces enhances NTM resilience against flushing and disinfection.

Key Insights:

• NTM survival is facilitated by their resistance to common disinfectants like chlorine.
• Adaptations such as oligotrophic growth and desiccation tolerance enable NTM persistence in diverse water system conditions.
• The hydrophobic outer membrane is a critical factor in NTM's resistance to antimicrobial agents.

Outlook:

• Understanding NTM's ecological niche and resilience is crucial for managing their presence in water systems.
• Further research into NTM's adaptability, including high-temperature resistance, may inform public health strategies.
• Developing effective strategies to control NTM in drinking water requires addressing their unique survival mechanisms.