title: Inward facing conformations of the MetNI methionine ABC transporter: Implications for the mechanism of transinhibition.
abstract: Two new crystal structures of the Escherichia coli high affinity methionine uptake ATP Binding Cassette (ABC) transporter MetNI, purified in the detergents cyclohexyl-pentyl-β-D-maltoside (CY5) and n-decyl-β-D-maltopyranoside (DM), have been solved in inward facing conformations to resolutions of 2.9 and 4.0 Å, respectively. Compared to the previously reported 3.7 Å resolution structure of MetNI purified in n-dodecyl-β-D-maltopyranoside (DDM), the higher resolution of the CY5 data enabled significant improvements to the structural model in several regions, including corrections to the sequence registry, and identification of ADP in the nucleotide binding site. CY5 crystals soaked with selenomethionine established details of the methionine binding site in the C2 regulatory domain of the ABC subunit, including the displacement of the side chain of MetN residue methionine 301 by the exogenous ligand. When compared to the CY5 or DDM structures, the DM structure exhibits a significant repositioning of the dimeric C2 domains, including an unexpected register shift in the intermolecular β-sheet hydrogen bonding between monomers, and a narrowing of the nucleotide binding space. The immediate proximity of the exogenous methionine binding site to the conformationally variable dimeric interface provides an indication of how methionine binding to the regulatory domains might mediate the phenomenon of transinhibition.
authors.affiliation: Division of Chemistry and Chemical Engineering 114-96, California Institute of Technology, Pasadena, CA 91125, USA.
authors.forename: Eric
authors.initials: E
authors.lastname: Johnson
authors.forename: Phong T
authors.initials: PT
authors.lastname: Nguyen
authors.forename: Todd O
authors.initials: TO
authors.lastname: Yeates
authors.forename: Douglas C
authors.initials: DC
authors.lastname: Rees
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000378:metabolism; D000244:Adenosine Diphosphate / Q000737:chemistry / Q000378:metabolism; D000494:Allosteric Regulation; D001665:Binding Sites; D029968:Escherichia coli Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000378:metabolism; D008715:Methionine / Q000737:chemistry / Q000378:metabolism; D008958:Models, Molecular; D016297:Mutagenesis, Site-Directed; D025341:Principal Component Analysis; D011487:Protein Conformation; D012645:Selenomethionine / Q000737:chemistry / Q000378:metabolism
chemical_list: D018528:ATP-Binding Cassette Transporters; D029968:Escherichia coli Proteins; D000244:Adenosine Diphosphate; D012645:Selenomethionine; D008715:Methionine
references.citation: Methods Enzymol. 1997;276:523-30
references.pmid: 9048379
references.citation: Annu Rev Biochem. 2004;73:241-68
references.pmid: 15189142
references.citation: J Bacteriol. 1977 Jan;129(1):207-16
references.pmid: 318639
references.citation: Nat Rev Mol Cell Biol. 2009 Mar;10(3):218-27
references.pmid: 19234479
references.citation: Proc Natl Acad Sci U S A. 2011 Sep 13;108(37):15152-6
references.pmid: 21825153
references.citation: J Bacteriol. 1974 Aug;119(2):401-9
references.pmid: 4604763
references.citation: Nature. 1966 Aug 27;211(5052):969-70
references.pmid: 5968307
references.citation: J Gen Physiol. 1969 Jul 1;54(1):95-113
references.pmid: 19873660
references.citation: Biophys J. 1997 Dec;73(6):2891-6
references.pmid: 9414203
references.citation: Mol Cell. 2000 Nov;6(5):1207-18
references.pmid: 11106758
references.citation: J Biol Chem. 2010 Dec 3;285(49):37987-94
references.pmid: 20861011
references.citation: J Bacteriol. 1974 Jan;117(1):232-41
references.pmid: 4587605
references.citation: J Biomol Struct Dyn. 2001 Aug;19(1):115-28
references.pmid: 11565843
references.citation: Acta Crystallogr D Biol Crystallogr. 1994 Sep 1;50(Pt 5):760-3
references.pmid: 15299374
references.citation: Arch Microbiol. 2003 Aug;180(2):88-100
references.pmid: 12819857
references.citation: Acta Crystallogr D Biol Crystallogr. 2006 Jan;62(Pt 1):72-82
references.pmid: 16369096
references.citation: Science. 2011 Jun 3;332(6034):1202-5
references.pmid: 21566157
references.citation: Angew Chem Int Ed Engl. 1998 Sep 18;37(17):2320-2328
references.pmid: 29710959
references.citation: Microbiol Mol Biol Rev. 2008 Jun;72(2):317-64, table of contents
references.pmid: 18535149
references.citation: Methods Enzymol. 1997;277:53-64
references.pmid: 18488305
references.citation: Science. 2007 Jan 19;315(5810):373-7
references.pmid: 17158291
references.citation: Acta Crystallogr D Biol Crystallogr. 1997 May 1;53(Pt 3):240-55
references.pmid: 15299926
references.citation: Nature. 2006 Sep 14;443(7108):180-5
references.pmid: 16943773
references.citation: Cell. 2000 Jun 23;101(7):789-800
references.pmid: 10892749
references.citation: FEMS Microbiol Rev. 1990 Aug;6(4):429-46
references.pmid: 2147378
references.citation: Science. 2008 Jul 11;321(5886):250-3
references.pmid: 18621668
references.citation: Mol Cell. 2002 Jul;10(1):139-49
references.pmid: 12150914
references.citation: Proteins. 1993 Dec;17(4):412-25
references.pmid: 8108382
references.citation: Mol Cell. 2009 Feb 27;33(4):528-36
references.pmid: 19250913
references.citation: J Bacteriol. 2002 Sep;184(17):4930-2
references.pmid: 12169620
references.citation: J Physiol. 1952 Sep;118(1):23-39
references.pmid: 13000688
references.citation: J Mol Biol. 2009 Oct 9;392(5):1242-52
references.pmid: 19646995
references.citation: Curr Opin Struct Biol. 2007 Aug;17(4):412-8
references.pmid: 17723295
references.citation: Science. 2008 Jul 11;321(5886):246-50
references.pmid: 18511655
references.citation: Acta Crystallogr D Biol Crystallogr. 2010 Apr;66(Pt 4):486-501
references.pmid: 20383002
references.citation: Nature. 2007 Mar 8;446(7132):213-6
references.pmid: 17322901
references.citation: Protein Sci. 2010 May;19(5):1031-43
references.pmid: 20440841
references.citation: EMBO J. 1997 Jun 2;16(11):3066-77
references.pmid: 9214624
references.citation: Annu Rev Cell Biol. 1992;8:67-113
references.pmid: 1282354
references.citation: Acta Crystallogr D Biol Crystallogr. 2010 Feb;66(Pt 2):213-21
references.pmid: 20124702
references.citation: FEMS Microbiol Lett. 1999 Oct 15;179(2):187-202
references.pmid: 10518715
references.citation: Annu Rev Biochem. 1986;55:397-425
references.pmid: 3527048
references.citation: Acta Crystallogr D Biol Crystallogr. 2010 Feb;66(Pt 2):125-32
references.pmid: 20124692
references.citation: Proc Natl Acad Sci U S A. 2006 May 23;103(21):8060-5
references.pmid: 16690741
references.citation: Nature. 2007 Nov 22;450(7169):515-21
references.pmid: 18033289
references.citation: Mol Microbiol. 2010 Sep;77(6):1354-66
references.pmid: 20659291
references.citation: J Appl Crystallogr. 2007 Aug 1;40(Pt 4):658-674
references.pmid: 19461840
references.citation: J Bacteriol. 2002 Oct;184(19):5513-7
references.pmid: 12218041
references.citation: Science. 2002 May 10;296(5570):1091-8
references.pmid: 12004122
references.citation: Philos Trans R Soc Lond B Biol Sci. 2009 Jan 27;364(1514):239-45
references.pmid: 18957379