title: Effect of low temperature on highly unsaturated fatty acid biosynthesis in activated sludge.
abstract: Low temperature is a limiting factor for the microbial activity of activated sludge for sewage treatment plant in winter. Highly unsaturated fatty acid (UFA) biosynthesis, phospholipid fatty acid (PLFA) constituents and microbial structure in activated sludge at low temperature were investigated. Over 12 gigabases of metagenomic sequence data were generated with the Illumina HiSeq 2000 platform. The result showed 43.11% of phospholipid fatty acid (PLFA) in the activated sludge participated in UFA biosynthesis, and γ-Linolenic could be converted to Arachidonic acid at low temperature. The highly UFA biosynthesis in activated sludge was n-6 highly UFA biosynthesis, rather than n-3 highly UFA biosynthesis. The microbial community structures of activated sludge were analyzed by PLFA and high-throughput sequencing (HiSeq) simultaneously. Acidovorax, Pseudomonas, Flavobacterium and Polaromonas occupied higher percentage at 5°C, and genetic changes of highly UFA biosynthesis derived from microbial community structures change.
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, Jiangsu, PR China.
authors.forename: Su
authors.initials: S
authors.lastname: He
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, Jiangsu, PR China.
authors.forename: Li-Li
authors.initials: LL
authors.lastname: Ding
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, Jiangsu, PR China.
authors.forename: Ke
authors.initials: K
authors.lastname: Xu
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, Jiangsu, PR China.
authors.forename: Jin-Ju
authors.initials: JJ
authors.lastname: Geng
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, Jiangsu, PR China. Electronic address: hqren@nju.edu.cn.
authors.forename: Hong-Qiang
authors.initials: HQ
authors.lastname: Ren
mesh_terms: D016718:Arachidonic Acid / Q000378:metabolism; D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors / Q000382:microbiology; D005227:Fatty Acids / Q000096:biosynthesis*; D005231:Fatty Acids, Unsaturated; D059014:High-Throughput Nucleotide Sequencing; D056186:Metagenomics; D010743:Phospholipids; D012722:Sewage / Q000382:microbiology*; D013696:Temperature; D018505:Waste Management / Q000379:methods; D017965:gamma-Linolenic Acid / Q000378:metabolism
chemical_list: D005227:Fatty Acids; D005231:Fatty Acids, Unsaturated; D010743:Phospholipids; D012722:Sewage; D016718:Arachidonic Acid; D017965:gamma-Linolenic Acid
keywords: Activated sludge; High-throughput sequencing; Highly UFA biosynthesis; Low temperature; Unsaturated fatty acid