title: Metagenomic analysis of cadmium and copper resistance genes in activated sludge of a tannery wastewater treatment plant.
abstract: In order to comprehensively characterize the copper and cadmium resistance in activated sludge of a tannery wastewater treatment plant, a resistance protein database of the two heavy metals was manually created by retrieving annotated sequences and related information from the public databases and published literatures. The metagenomic DNA was extracted from the activated sludge for Illumina high-throughput sequencing, and the obtained 11,973,394 clean reads (1.61 Gb) were compared against the established databases using BLAST tool. Annotations of the BLAST hits showed that 222 reads (0.019 per thousand) and 197 reads (0.016 per thousand) were identified as copper and cadmium resistance genes, respectively. Among the identified cadmium resistance genes, czcA encoding cobalt-zinc-cadmium resistance protein had the highest abundance (83 reads, 0.0069 per thousand), which was further confirmed by annotation of the open reading frames predicted with the assembly contigs. Among the copper resistance genes, copA (66 reads, 0.0055 per thousand) was most abundant, followed by copK and cusR. Alignment against the Clusters of Orthologous Groups (COG) database also suggested that 87.26% of the matched reads were grouped in COG0474 (cation transport ATPase). This study may be practically helpful for exploring various functional genes in the environment using high-throughput sequencing and bioinformatics methods.
authors.forename: Shuyu
authors.initials: S
authors.lastname: Jia
authors.forename: Zhu
authors.initials: Z
authors.lastname: Wang
authors.forename: Xu-Xiang
authors.initials: XX
authors.lastname: Zhang
authors.forename: Bo
authors.initials: B
authors.lastname: Liu
authors.forename: Weixin
authors.initials: W
authors.lastname: Li
authors.forename: Shupei
authors.initials: S
authors.lastname: Cheng
mesh_terms: D001419:Bacteria / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D002104:Cadmium / Q000737:chemistry*; D003300:Copper / Q000737:chemistry*; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology; D016680:Genome, Bacterial; D007220:Industrial Waste / Q000032:analysis*; D013633:Tanning; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical
chemical_list: D007220:Industrial Waste; D014874:Water Pollutants, Chemical; D002104:Cadmium; D003300:Copper