Identification of the Microbial Community Structure and Potential Mechanism of Environmental Adaptation in Contaminated Environments.

Purpose: To assess the bacterial community structure and the possible mechanism underlying the environmental adaption in contaminated habitats.Methods: The 60-mer oligonucleotide multibacterial microarray (GSE38004) was downloaded from the Gene Expression Omnibus database. The changes in the abundance of bacterial populations and genes in contaminated habitats were assessed based on the gene expression profiles. Then the potential function of the genes and their involved pathways were predicted by a bioinformatics approach.Results: A total of 25 bacterial populations had different abundance between contaminated habitats and uncontaminated area, of whichSphingobium herbicidovorans(S. herbicidovorans)andPseudomonas pavonaceae (P. pavonaceae)involved in 23 populations were determined to have higher abundance in contaminated areas. Additionally, 184 genes involved in anaerobic respiration and cellular respiration were detected to have potential bioremediation. The genes ofMDH(Mannitol-1-phosphate/altronate dehydrogenases) andfadE(acyl-CoA dehydrogenase) may play key roles in the mechanism of metabolic adaption.Conclusions:S. herbicidovoransandP. pavonaceaewere the predominant bacterial groups in contaminated sites for the various metabolic potential and antibiotic resistances. The significant genes (MDH, fadE) and pathways (citrate cycle, pyruvate metabolism, fatty acid metabolism) played key roles in the adaptive response of microorganisms in contaminated environment. [ABSTRACT FROM AUTHOR]