title: Functional and genetic characterization of hydrocarbon biodegrader and exopolymer-producing clones from a petroleum reservoir metagenomic library.
abstract: Microbial degradation of petroleum is a worldwide issue, which causes physico-chemical changes in its compounds, diminishing its commercial value. Biosurfactants are chemically diverse molecules that can be produced by several microorganisms and can enable microbial access to hydrocarbons. In order to investigate both microbial activities, function-driven screening assays for biosurfactant production and hydrocarbon biodegradation were carried out from a metagenomic fosmid library. It was constructed from the total DNA extracted from aerobic and anaerobic enrichments from a Brazilian biodegraded petroleum sample. A sum of 10 clones were selected in order to evaluate their ability to produce exopolymers (EPS) with emulsifying activity, as well as to characterize the gene sequences, harbored by the fosmid clones, through 454 pyrosequencing. Functional analyses confirmed the ability of some clones to produce surfactant compounds. Regarding hydrocarbon as microbial carbon sources, n-alkane (in mixture or not) and naphthalene were preferentially consumed as substrates. Analysis of sequence data set revealed the presence of genes related to xenobiotics biodegradation and carbohydrate metabolism. These data were corroborated by the results of hydrocarbon biodegradation and biosurfactant production detected in the evaluated clones.
authors.affiliation: a Federal University of São Paulo - UNIFESP , Diadema , SP , Brazil.
authors.forename: Suzan P
authors.initials: SP
authors.lastname: Vasconcellos
authors.affiliation: b Microbial Resources Division, Research Center for Chemistry , Biology and Agriculture (CPQBA), University of Campinas - UNICAMP , Campinas , SP , Brazil.
authors.forename: Isabel N
authors.initials: IN
authors.lastname: Sierra-Garcia
authors.affiliation: b Microbial Resources Division, Research Center for Chemistry , Biology and Agriculture (CPQBA), University of Campinas - UNICAMP , Campinas , SP , Brazil.
authors.forename: Bruna M
authors.initials: BM
authors.lastname: Dellagnezze
authors.affiliation: c Center of Molecular Biology and Genetic Engineering - CBMEG/UNICAMP , Campinas , SP , Brazil.
authors.forename: Renato
authors.initials: R
authors.lastname: Vicentini
authors.affiliation: d CSIRO , North Ryde , NSW , Australia.
authors.forename: David
authors.initials: D
authors.lastname: Midgley
authors.affiliation: e Department of Microbiology , Federal University of Viçosa - UFV, CEP 36570-000 , Viçosa , MG , Brazil.
authors.forename: Cynthia C
authors.initials: CC
authors.lastname: Silva
authors.affiliation: f PETROBRAS/R&D Center , Rio de Janeiro , Brazil.
authors.forename: Eugenio V
authors.initials: EV
authors.lastname: Santos Neto
authors.affiliation: d CSIRO , North Ryde , NSW , Australia.
authors.forename: Herbert
authors.initials: H
authors.lastname: Volk
authors.affiliation: d CSIRO , North Ryde , NSW , Australia.
authors.forename: Philip
authors.initials: P
authors.lastname: Hendry
authors.affiliation: b Microbial Resources Division, Research Center for Chemistry , Biology and Agriculture (CPQBA), University of Campinas - UNICAMP , Campinas , SP , Brazil.
authors.forename: Valéria M
authors.initials: VM
authors.lastname: Oliveira
mesh_terms: D001673:Biodegradation, Environmental; D001938:Brazil; D015723:Gene Library; D006838:Hydrocarbons / Q000378:metabolism*; D054892:Metagenome; D010578:Petroleum / Q000378:metabolism*
chemical_list: D006838:Hydrocarbons; D010578:Petroleum
keywords: Fosmid clones; biodegradation; biosurfactant; heterologous expression; hydrocarbon