Profiling bulking and foaming bacteria in activated sludge by high throughput sequencing.

Area of Science:

• Environmental microbiology
• Wastewater treatment technologies

Background:

• Bulking and foaming bacteria (BFB) are common in activated sludge but their full community profile is poorly understood.
• Conventional methods limit comprehensive investigation of sub-dominant bacterial groups.

Purpose of the Study:

• To characterize the community structure of BFB in activated sludge using high-throughput sequencing.
• To identify dominant BFB groups and their distribution patterns across global wastewater treatment plants.

Main Methods:

• Utilized high-throughput sequencing of 16S rRNA gene V4 pyrotags.
• Developed a dedicated database for BFB groups using full-length 16S rRNA gene sequences.
• Employed local BLAST for taxonomic assignment and community analysis.

Main Results:

• BFB constituted 1.86% to 8.99% of the microbial community in analyzed activated sludge samples.
• 'Nostocoida limicola' I and II, Mycobacterium fortuitum, Type 1863, and 'Microthrix parvicella' were the most abundant and frequent BFB.
• BFB communities exhibited biogeographical and technological distribution patterns.

Conclusions:

• High-throughput sequencing provides a powerful tool for investigating sub-dominant bacterial groups like BFB.
• Understanding BFB community dynamics is crucial for optimizing wastewater treatment processes.
• The study provides a foundation for developing targeted molecular tools for BFB detection and management.