title: Heterologous expression and purification of a multiheme cytochrome from a Gram-positive bacterium capable of performing extracellular respiration.
abstract: Microbial electrochemical technologies are emerging as environmentally friendly biotechnological processes. Recently, a thermophilic Gram-positive bacterium capable of electricity production in a microbial fuel cell was isolated. Thermincola potens JR contains several multiheme c-type cytochromes that were implicated in the process of electricity production. In order to understand the molecular basis by which Gram-positive bacteria perform extracellular electron transfer, the relevant proteins need to be characterized in detail. Towards this end, a chimeric gene containing the signal peptide from Shewanella oneidensis MR-1 small tetraheme cytochrome c (STC) and the gene sequence of the target protein TherJR_0333 was constructed. This manuscript reports the successful expression of this chimeric gene in the Gram-negative bacterium Escherichia coli and its subsequent purification and characterization. This methodology opens the possibility to study other multiheme cytochromes from Gram-positive bacteria, allowing the extracellular electron transfer mechanisms of this class of organisms to be unraveled.
authors: Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República - EAN, 2780-157 Oeiras, Portugal.
authors: N L
authors: NL
authors: Costa
authors: Energy Bioscience Institute, University of California, Berkeley, CA 94720, United States.
authors: H K
authors: HK
authors: Carlson
authors: Energy Bioscience Institute, University of California, Berkeley, CA 94720, United States; Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, United States.
authors: J D
authors: JD
authors: Coates
authors: Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República - EAN, 2780-157 Oeiras, Portugal.
authors: R O
authors: RO
authors: Louro
authors: Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República - EAN, 2780-157 Oeiras, Portugal. Electronic address: cpaquete@itqb.unl.pt.
authors: C M
authors: CM
authors: Paquete
mesh_terms: D001426:Bacterial Proteins / Q000096:biosynthesis* / Q000235:genetics; D045304:Cytochromes c / Q000096:biosynthesis* / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D006094:Gram-Positive Bacteria / Q000201:enzymology* / Q000235:genetics; D010101:Oxygen Consumption; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000235:genetics; D020592:Shewanella / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D011994:Recombinant Proteins; D045304:Cytochromes c
keywords: Extracellular electron transfer; Gram-positive bacteria; Microbial fuel cells; Multiheme-cytochrome; Thermincola