DNA release from environmental bacteria

• Main Author: Chua, Isaac Yi Xian
• Other Authors: Cao Bin
• Format: Final Year Project
• Language: English
• Published: 2019
• Subjects: DRNTU::Engineering::Environmental engineering
• Online Access: http://hdl.handle.net/10356/76416
• Institution: Nanyang Technological University

One major challenge of the 21st century is to provide clean drinking water, but it is often hampered by various issues. One such issue in an urban setting is the presence of biofilms found in drinking water distribution systems. Biofilms start forming in the distribution systems by bacteria attaching to the surfaces of pipes and begin to produce extracellular polymers substances (EPS) which would in turn provide attachment for other bacteria. Numerous studies have been conducted in recent years on the interaction between biofilms and disinfectants for the formation of disinfection-by products (DBPs). However, the interaction between disinfectants and cells in the distribution system has often been neglected. Such interactions may lead to cell lysis, thereby releasing intracellular biomolecules into the system, particularly DNA. When released into the environment, it can persist as extracellular DNA or exDNA and would have various implications such as affecting the formation of biofilms or ultimately, leading to the spread of antibiotic resistant genes through horizontal gene transfer. In this report, the interaction between Pseudomonas aeruginosa and monochloramine will be investigated to determine the effects of the interaction, quantify the amount of exDNA that is released by Pseudomonas aeruginosa after exposure and lastly, investigate the mechanisms that Pseudomonas aeruginosa used in the release of DNA.