title: Structure of the type IVa major pilin from the electrically conductive bacterial nanowires of Geobacter sulfurreducens.
abstract: Several species of δ proteobacteria are capable of reducing insoluble metal oxides as well as other extracellular electron acceptors. These bacteria play a critical role in the cycling of minerals in subsurface environments, sediments, and groundwater. In some species of bacteria such as Geobacter sulfurreducens, the transport of electrons is proposed to be facilitated by filamentous fibers that are referred to as bacterial nanowires. These nanowires are polymeric assemblies of proteins belonging to the type IVa family of pilin proteins and are mainly comprised of one subunit protein, PilA. Here, we report the high resolution solution NMR structure of the PilA protein from G. sulfurreducens determined in detergent micelles. The protein is >85% α-helical and exhibits similar architecture to the N-terminal regions of other non-conductive type IVa pilins. The detergent micelle interacts with the first 21 amino acids of the protein, indicating that this region likely associates with the bacterial inner membrane prior to fiber formation. A model of the G. sulfurreducens pilus fiber is proposed based on docking of this structure into the fiber model of the type IVa pilin from Neisseria gonorrhoeae. This model provides insight into the organization of aromatic amino acids that are important for electrical conduction.
authors: From the Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99354 and.
authors: Patrick N
authors: PN
authors: Reardon
authors: Karl T
authors: KT
authors: Mueller
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D003902:Detergents / Q000737:chemistry; D004553:Electric Conductivity; D036781:Fimbriae Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D010861:Fimbriae, Bacterial / Q000378:metabolism; D045302:Geobacter / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D008823:Micelles; D008958:Models, Molecular; D008969:Molecular Sequence Data; D053770:Nanowires / Q000737:chemistry; D011108:Polymers / Q000737:chemistry / Q000378:metabolism*; D011485:Protein Binding; D017433:Protein Structure, Secondary; D017386:Sequence Homology, Amino Acid
chemical_list: D001426:Bacterial Proteins; D003902:Detergents; D008823:Micelles; D011108:Polymers; D036781:Fimbriae Proteins
keywords: Bacterial Metabolism; Bioenergetics; Electron Transport; Membrane Proteins; NMR; Pili; Structural Biology
references: J Bacteriol. 2007 Mar;189(5):2069-76
references: 17172336
references: Methods Enzymol. 1990;185:161-6
references: 2199778
references: J Comput Chem. 2004 Oct;25(13):1605-12
references: 15264254
references: Appl Microbiol Biotechnol. 2012 Jan;93(1):41-8
references: 22072194
references: Adv Microb Physiol. 2004;49:219-86
references: 15518832
references: Mol Microbiol. 2007 Jul;65(1):12-20
references: 17581116
references: Appl Environ Microbiol. 2006 Nov;72(11):7345-8
references: 16936064
references: Nature. 2005 Jun 23;435(7045):1098-101
references: 15973408
references: Bioinformatics. 2009 May 1;25(9):1189-91
references: 19151095
references: Microbiol Mol Biol Rev. 2012 Dec;76(4):740-72
references: 23204365
references: J Biol Chem. 2011 Dec 23;286(51):44254-44265
references: 22027840
references: Nucleic Acids Res. 2010 Jul;38(Web Server issue):W695-9
references: 20439314
references: Proteins. 2007 Mar 1;66(4):778-95
references: 17186527
references: Mol Cell. 2003 May;11(5):1139-50
references: 12769840
references: Mol Syst Biol. 2011 Oct 11;7:539
references: 21988835
references: J Biomol NMR. 1999 Mar;13(3):289-302
references: 10212987
references: Acta Crystallogr D Biol Crystallogr. 2010 Jan;66(Pt 1):12-21
references: 20057044
references: Acta Crystallogr D Biol Crystallogr. 1998 Sep 1;54(Pt 5):905-21
references: 9757107
references: mBio. 2013 Mar 12;4(2):e00105-13
references: 23481602
references: J Mol Biol. 1997 Oct 17;273(1):283-98
references: 9367762
references: Methods Mol Biol. 2004;278:313-52
references: 15318002
references: Nat Rev Microbiol. 2004 May;2(5):363-78
references: 15100690
references: Science. 1988 Jun 3;240(4857):1319-21
references: 17815852
references: ChemSusChem. 2012 Jun;5(6):1039-46
references: 22614997
references: Science. 2001 Aug 24;293(5534):1444-6
references: 11520973
references: Proc Natl Acad Sci U S A. 1991 Apr 15;88(8):3281-5
references: 1901657
references: J Biomol NMR. 2001 Nov;21(3):249-61
references: 11775741
references: J Phys Chem A. 2012 Aug 2;116(30):8023-30
references: 22779741
references: Proteins. 2005 Jun 1;59(4):662-72
references: 15822098
references: J Mol Biol. 1996 Oct 4;262(4):407-12
references: 8893852
references: Environ Sci Technol. 2006 Sep 1;40(17):5181-92
references: 16999087
references: Protein Eng Des Sel. 2004 Aug;17(8):613-24
references: 15388845
references: Proc Natl Acad Sci U S A. 2010 Jun 22;107(25):11358-63
references: 20534431
references: Nat Nanotechnol. 2011 Aug 07;6(9):573-9
references: 21822253
references: ChemSusChem. 2012 Jun;5(6):1099-105
references: 22615023
references: Appl Environ Microbiol. 1988 Jun;54(6):1472-80
references: 16347658
references: Mol Cell. 2006 Sep 1;23(5):651-62
references: 16949362
references: Biochem Soc Trans. 2012 Dec 1;40(6):1186-90
references: 23176452
references: Biochim Biophys Acta. 2010 Sep;1797(9):1563-72
references: 20460102