Microbial community in anoxic-oxic-settling-anaerobic sludge reduction process revealed by 454 pyrosequencing analysis.
Modification of the anoxic-oxic (AO) process by inserting a sludge holding tank (SHT) into the sludge return line forms an anoxic-oxic-settling-anaerobic (A+OSA) process that can achieve a 48.98% sludge reduction rate. The 454 pyrosequencing method was used to obtain the microbial communities of the AO and A+OSA processes. Results showed that the microbial community structures of the 2 processes were different as a result of the SHT insertion. Bacteria assigned to the phyla Proteobacteria and Bacteroidetes commonly existed and dominated the microbial populations of the 2 processes. However, the relative abundance of these populations shifted in the presence of SHT. The relative abundance of Proteobacteria decreased during the A+OSA process. A specific comparison at the class level showed that Sphingobacteria was enriched in the A+OSA process. The result suggested that the fermentative bacteria Sphingobacteria may have key functions in reducing the sludge from the A+OSA process. Uncultured Nitrosomonadaceae gradually became the dominant ammonia-oxidizing bacteria, and the nitrite-oxidizing bacterium Nitrospira was enriched in the A+OSA process. Both occurrences were favorable for stabilized nitrogen removal. The known denitrifying species in the A+OSA process were similar to those in the AO process; however, their relative abundance also decreased.
a Faculty of Urban Construction and Environmental Engineering, Chongqing University, Chongqing, People's Republic of China.
Xinqiang
X
Ning
Wenwen
W
Qiao
Lei
L
Zhang
Xu
X
Gao
D000332:Aerobiosis; D000693:Anaerobiosis; D041963:Bacteroidetes / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D019149:Bioreactors; D020459:Genes, rRNA; D064307:Microbiota; D010802:Phylogeny; D020560:Proteobacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D012722:Sewage / Q000382:microbiology*; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater / Q000382:microbiology*
D012336:RNA, Ribosomal, 16S; D012722:Sewage; D062065:Wastewater
454 pyrosequencing; communauté bactérienne; microbial community; oxic-settling-anoxic process; processus oxique-sédimentation-anoxique; pyroséquençage 454; réduction de boue; sludge reduction