Physiological traits of bacterial strains isolated from phenol-degrading aerobic granules.
The physiological characteristics of ten bacterial strains isolated from phenol-degrading aerobic granules were evaluated in order to identify competitive traits for dominant growth in aerobic granules. The ten strains showed a wide diversity in specific growth rates and oxygen utilization kinetics, and could be divided into four catabolic types of phenol degradation. While some strains degraded phenol mainly via the meta pathway or the ortho pathway, other strains degraded phenol via both these pathways. The ten strains also exhibited high levels of autoaggregation and coaggregation activity. Within the collection of ten strains, 36.7% of all possible strain pairings displayed a measurable degree of coaggregation. Strain PG-08 possessed the strongest autoaggregation activity and showed significant coaggregation (coaggregation indices of 67% to 74%) with PG-02. The three strains PG-01, PG-02 and PG-08 belonging to dominant groups in the granules possessed different competitive characteristics. Microcosm experiments showed the three strains could not coexist at the high phenol concentration of 250 mg L(-1), but could coexist at lower phenol concentrations in a spatially heterogeneous environment. This study illustrated that the spatial heterogeneity provided by the aerobic granules led to niche differentiation and increased physiological diversity in the resident microbial community.
Jiang
He-Long
HL
Environmental Engineering Research Centre, School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore. hljiang@ntu.edu.sg
Tay
Stephen Tiong-Lee
ST
Maszenan
Abdul Majid
AM
Tay
Joo-Hwa
JH
D000332:Aerobiosis; D001420:Bacteria, Aerobic / Q000254:growth & development / Q000302:isolation & purification* / Q000378:metabolism*; D001422:Bacterial Adhesion; D018407:Bacterial Physiological Phenomena; D001673:Biodegradation, Environmental; D015169:Colony Count, Microbial; D005427:Flocculation; D010101:Oxygen Consumption; D010636:Phenols / Q000378:metabolism*; D014871:Water Microbiology
D010636:Phenols