Chlorine stress mediates microbial surface attachment in drinking water systems

Area of Science:

• Environmental microbiology
• Water treatment technologies
• Biofilm formation

Background:

• Microbial attachment to drinking water pipes is a major concern for water safety.
• Biofilm development mechanisms, particularly initial microbial surface attachment, are not fully understood.
• Disinfection efficacy is often compromised by microbial survival on pipe surfaces.

Purpose of the Study:

• To investigate the role of environmental stress-mediated cell motility in microbial surface attachment.
• To elucidate the mechanisms of initial microbial attachment in drinking water distribution systems under chlorination stress.
• To understand how chlorine concentration affects microbial attachment and biofilm formation.

Main Methods:

• Combined experimental and mathematical modeling approaches.
• Investigated microbial attachment in drinking water distribution systems exposed to varying chlorination levels.
• Developed a mathematical model to demonstrate the relationship between chlorination stress, cell motility, and attachment.

Main Results:

• Low chlorine concentrations (0.0-1.0 mg/L) promote initial microbial surface attachment.
• High chlorine concentrations (>1.0 mg/L) inhibit microbial attachment.
• Chlorination stress-mediated microbial cell motility regulates cell-wall collision frequency, controlling initial attachment.

Conclusions:

• Chlorine's effect on microbial attachment is concentration-dependent.
• Transport and decay of chlorine in pipelines influence cell motility and initial attachment.
• Provides mechanistic insights into microbial attachment under disinfection stress, informing water safety protocols.