title: DNA-SIP reveals that Syntrophaceae play an important role in methanogenic hexadecane degradation.
abstract: The methanogenic degradation of linear alkanes is a common process in oil-impacted environments. However, little is known about the key players involved in this process. Here, the hexadecane-degrading organisms in a methanogenic, hexadecane-degrading consortium designated M82 obtained from Shengli oilfield and maintained at 35°C for over 4 years, were identified by DNA-stable isotope probing with UL-¹³C-hexadecane, followed by density-resolved terminal restriction fragment length polymorphism (T-RFLP) analysis, cloning and phylogenetic analysis of 16S rRNA gene fragments. Compared to the fractions of the ¹²C treatment, the relative abundance of two phylotypes significantly increased in the heavy fractions of the ¹³C-hexadecane incubated microcosm. One belongs to a uncultured member of the bacterial family Syntrophaceae, which show 95-97% rRNA sequence identity with Smithella propionica, and the other is affiliated with Methanoculleus receptaculi (>99% sequence identity). The results of the present study prove the significant role of uncultured Syntrophaceae in degradation of hexadecane, probably through syntrophic interactions with hydrogenotrophic methanogens.
authors.affiliation: Key Laboratory of Development and Application of Rural Renewable Energy, Biogas Institute of Ministry of Agriculture, Chengdu, Sichuan, People's Republic of China.
authors.forename: Lei
authors.initials: L
authors.lastname: Cheng
authors.forename: Chen
authors.initials: C
authors.lastname: Ding
authors.forename: Qiang
authors.initials: Q
authors.lastname: Li
authors.forename: Qiao
authors.initials: Q
authors.lastname: He
authors.forename: Li-Rong
authors.initials: LR
authors.lastname: Dai
authors.forename: Hui
authors.initials: H
authors.lastname: Zhang
mesh_terms: D000473:Alkanes / Q000378:metabolism*; D004269:DNA, Bacterial / Q000235:genetics / Q000302:isolation & purification; D020564:Deltaproteobacteria / Q000235:genetics* / Q000378:metabolism*; D020459:Genes, rRNA; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics / Q000302:isolation & purification
chemical_list: D000473:Alkanes; D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S; C007932:n-hexadecane