Abstract
Acidithiobacillus ferrooxidans is one of the most widely used microorganisms in bioleaching operations to recover copper from low-grade copper sulfide ores. This work aimed to investigate the relative expression of genes related to the iron uptake system when A. ferrooxidans LR was maintained in contact with chalcopyrite or bornite as the sole energy source. Real-time quantitative PCR analysis revealed that the presence of bornite had no effect on the expression of seven genes related to the siderophore-mediated Fe(III) uptake system, while in the presence of chalcopyrite the expression of the genes was up-regulated. Bioinformatic analysis of the genomic region where these genes were found revealed the existence of three new putative DNA-binding sequences for the ferric iron uptake transcriptional regulator (Fur). Electrophoretic mobility shift assays demonstrated that a purified A. ferrooxidans His-tagged Fur protein was able to bind in vitro to each of these putative Fur boxes, suggesting that Fur regulated the expression of these genes. The expression of fur and two known Fur-regulated genes, mntH and dsrK, was also investigated in the presence of chalcopyrite. While the expression of fur and mntH was up-regulated, the expression of dsrK was down-regulated. The low amount of ferrous iron in the medium was probably responsible for the up-regulation of fur and the genes related to the siderophore-mediated Fe(III) uptake system when A. ferrooxidans LR was kept in the presence of chalcopyrite. A homology model of the A.ferrooxidans Fur was constructed and revealed that the putative DNA-binding surface presents conserved positively charged residues, supporting a previously suggested mode of interaction with DNA. The up-regulation of fur and the siderophore-mediated Fe(III) uptake genes, and the down-regulation of dsrK suggest that in the presence of chalcopyrite Fur acts as a transcription inducer and repressor.
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References
Altschul SF, Madden TL, Schaffer AA, Zhang J, Zhang Z, Miller W, Lipman DJ (1997) Gapped BLAST and PSI-BLAST: a new generation of protein database search programs. Nucleic Acids Res 25:3389–3402
Andrews SC, Robinson AK, Rodríguez-Quiñones F (2003) Bacterial iron homeostasis. FEMS Microbiol Rev 27:215–237
Bairoch A, Boeckmann B, Ferro S, Gasteiger E (2004) Swiss-Prot: juggling between evolution and stability. Brief Bioinform 5:39–55
Bevilaqua D, Diéz-Perez I, Fugivara CS, Sanz F, Garcia O Jr, Benedetti AV (2003) Characterization of bornite (Cu5FeS4) electrodes in the presence of the bacterium Acidithiobacillus ferrooxidans. J Braz Chem Soc 14:637–644
Carlos C, Reis FC, Vicentini R, Madureira DJ, Ottoboni LMM (2008) The rus operon genes are differentially regulated when Acidithiobacillus ferrooxidans LR is kept in contact with metal sulfides. Curr Microbiol 57:375–380
DeLano WL (2002) The PyMOL Molecular Graphics System on the World Wide Web http://www.pymol.org
Edgar RC (2004) MUSCLE: multiple sequence alignment with high accuracy and high throughput. Nucleic Acids Res 32:1792–1797
Ferraz LFC, Verde LCL, Reis FC, Alexandrino F, Felício AP, Novo MTM, Garcia O Jr, Ottoboni LMM (2010) Gene expression modulation by chalcopyrite and bornite in Acidithiobacillus ferrooxidans. Arch Microbiol 192:531–540
Garcia O Jr (1991) Isolation and purification of Thiobacillus ferrooxidans and Thiobacillus thiooxidans from some coal and uranium mines of Brazil. Rev Microbiol 22:1–6
Gouet P, Courcelle E, Stuart DI, Metoz F (1999) ESPript: analysis of multiple sequence alignments in PostScript. Bioinformatics 15:305–308
Griggs DW, Tharp BB, Konisky J (1987) Cloning and promoter identification of the iron-regulated cir gene of Escherichia coli. J Bacteriol 169:5343–5352
Hall HK, Foster JW (1996) The role of fur in the acid tolerance response of Salmonella typhimurium is physiologically and genetically separable from its role in iron acquisition. J Bacteriol 178:5683–5691
Kehres DG, Zaharik ML, Finlay BB, Maguire ME (2000) The NRAMP proteins of Salmonella typhimurium and Escherichia coli are selective manganese transporters involved in the response to reactive oxygen. Mol Microbiol 36:1085–1100
Livak KJ, Schmittgen TD (2001) Analysis of relative gene expression data using real-time quantitative PCR and the 2−DDCT method. Methods 25:402–408
Makui H, Roig E, Cole ST, Helmann JD, Gros P, Cellier MF (2000) Identification of the Escherichia coli K-12 Nramp orthologue (MntH) as a selective divalent metal ion transporter. Mol Microbiol 35:1065–1078
Marchler-Bauer A, Anderson JB, Derbyshire MK, DeWeese-Scott C, Gonzales NR, Gwadz M, Hao L, He S, Hurwitz DI, Jackson JD, Ke Z, Krylov D, Lanczycki CJ, Liebert CA, Liu C, Lu F, Lu S, Marchler GH, Mullokandov M, Song JS, Thanki N, Yamashita RA, Yin JJ, Zhang D, Bryant SH (2007) CDD: a conserved domain database for interactive domain family analysis. Nucleic Acids Res 35:D237–D240
Paulino LC, Mello MP, Ottoboni LMM (2002) Differential gene expression in response to copper in Acidithiobacillus ferrooxidans analyzed by RNA arbitrarily primed polymerase chain reaction. Eletrophoresis 23:520–527
Pires RH, Venceslau SS, Morais F, Teixeira M, Xavier AV, Pereira IAC (2006) Characterization of the Desulfovibrio desulfuricans ATCC 27774 DsrMKJOP complex–a membrane-bound redox complex involved in the sulfate respiratory pathway. Biochemistry 45:249–262
Pohl E, Haller JC, Mijovilovich A, Meyer-Klaucke W, Garman E, Vasil ML (2003) Architecture of a protein central to iron homeostasis: crystal structure and spectroscopic analysis of the ferric uptake regulator. Mol Microbiol 47:903–915
Quatrini R, Lefimil C, Holmes DS, Jedlicki E (2005a) The ferric iron uptake regulator (Fur) from the extreme acidophile Acidithiobacillus ferrooxidans. Microbiology 151:2005–2015
Quatrini R, Jedlicki E, Holmes DS (2005b) Genomic insights into the iron uptake mechanisms of the biomining microorganism Acidithiobacillus ferrooxidans. J Ind Microbiol Biotechnol 32:606–614
Quatrini R, Lefimil C, Veloso FA, Pedroso I, Holmes DS, Jedlicki E (2007) Bioinformatic prediction and experimental verification of Fur-regulated genes in the extreme acidophile Acidithiobacillus ferrooxidans. Nucleic Acids Res 35:2153–2166
Rawlings DE (2002) Heavy metal mining using microbes. Annu Rev Microbiol 56:65–91
Reents H, Münch R, Dammeyer T, Jahn D, Härtig E (2006) The Fnr regulon of Bacillus subtilis. J Bacteriol 188:1103–1112
Rivas M, Seeger M, Holmes DS, Jedlicki E (2005) A lux-like quorum sensing system in the extreme acidophile Acidithiobacillus ferrooxidans. Biol Res 38:283–297
Sali A, Blundell TL (1993) Comparative protein modelling by satisfaction of spatial restraints. J Mol Biol 234:779–815
Schneider TD (1997) Information content of individual genetic sequences. J Theor Biol 189:427–441
Third KA, Cord-Ruwisch R, Watling HR (2000) The role of iron-oxidizing bacteria in stimulation or inhibition of chalcopyrite bioleaching. Hydrometallurgy 57:225–233
Tuovinen OH, Kelly DP (1973) Studies on the growth of Thiobacillus ferrooxidans. I. Use of membrane filters and ferrous iron agar to determine viable numbers, and comparison with 14 CO2-fixation and iron oxidation as measures of growth. Arch Mikrobiol 88:285–298
Vogel AI (1981) Análise inorgânica quantitativa, 4 edn. Guanabara Kogan, Rio de Janeiro
Yarzábal A, Appia-Ayme C, Ratouchniak J, Bonnefoy V (2004) Regulation of the expression of the Acidithiobacillus ferrooxidans rus operon encoding two cytochromes c, a cytochrome oxidase and rusticyanin. Microbiology 150:2113–2123
Acknowledgements
This work received financial support from Company Vale. LCLV received a fellowship from Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES). APF, LFCF and FA received fellowships from Fundação de Apoio à Ciência, Tecnologia e Educação (FACTE). LMMO and OGJr received research fellowships from Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq).
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Ferraz, L.F.C., Verde, L.C.L., Vicentini, R. et al. Ferric iron uptake genes are differentially expressed in the presence of copper sulfides in Acidithiobacillus ferrooxidans strain LR. Antonie van Leeuwenhoek 99, 609–617 (2011). https://doi.org/10.1007/s10482-010-9533-2
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DOI: https://doi.org/10.1007/s10482-010-9533-2