title: Analysis of peptides and proteins in their binding to GroEL.
abstract: The GroEL-GroES is an essential molecular chaperon system that assists protein folding in cell. Binding of various substrate proteins to GroEL is one of the key aspects in GroEL-assisted protein folding. Small peptides may mimic segments of the substrate proteins in contact with GroEL and allow detailed structural analysis of the interactions. A model peptide SBP has been shown to bind to a region in GroEL that is important for binding of substrate proteins. Here, we investigated whether the observed GroEL-SBP interaction represented those of GroEL-substrate proteins, and whether SBP was able to mimic various aspects of substrate proteins in GroE-assisted protein folding cycle. We found that SBP competed with substrate proteins, including α-lactalbumin, rhodanese, and malate dehydrogenase, in binding to GroEL. SBP stimulated GroEL ATP hydrolysis rate in a manner similar to that of α-lactalbumin. SBP did not prevent GroES from binding to GroEL, and GroES association reduced the ATPase rates of GroEL/SBP and GroEL/α-lactalbumin to a comparable extent. Binding of both SBP and α-lactalbumin to apo GroEL was dominated by hydrophobic interaction. Interestingly, association of α-lactalbumin to GroEL/GroES was thermodynamically distinct from that to GroEL with reduced affinity and decreased contribution from hydrophobic interaction. However, SBP did not display such differential binding behaviors to apo GroEL and GroEL/GroES, likely due to the lack of a contiguous polypeptide chain that links all of the bound peptide fragments. Nevertheless, studies using peptides provide valuable information on the nature of GroEL-substrate protein interaction, which is central to understand the mechanism of GroEL-assisted protein folding.
authors.affiliation: Interdisciplinary Biochemistry Program, Indiana University, 212 S. Hawthorne Dr., Bloomington, IN 47405, USA.
authors.forename: Yali
authors.initials: Y
authors.lastname: Li
authors.forename: Zhida
authors.initials: Z
authors.lastname: Zheng
authors.forename: Andrew
authors.initials: A
authors.lastname: Ramsey
authors.forename: Lingling
authors.initials: L
authors.lastname: Chen
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D002151:Calorimetry; D018834:Chaperonin 60 / Q000378:metabolism*; D010455:Peptides / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism*; D011485:Protein Binding; D011506:Proteins / Q000032:analysis* / Q000378:metabolism*; D013816:Thermodynamics
chemical_list: D018834:Chaperonin 60; D010455:Peptides; D011506:Proteins
references.citation: Nature. 1991 Jul 4;352(6330):36-42
references.pmid: 1676490
references.citation: J Biol Chem. 1995 Jan 20;270(3):1011-4
references.pmid: 7836352
references.citation: J Mol Biol. 2005 Apr 22;348(1):219-30
references.pmid: 15808865
references.citation: J Biol Chem. 2001 Aug 17;276(33):31257-64
references.pmid: 11395498
references.citation: Protein Sci. 1992 Mar;1(3):363-9
references.pmid: 1363913
references.citation: Mol Cell. 2007 May 11;26(3):415-26
references.pmid: 17499047
references.citation: FASEB J. 1996 Jan;10(1):102-9
references.pmid: 8566530
references.citation: Proc Natl Acad Sci U S A. 1986 Nov;83(21):8069-72
references.pmid: 3464944
references.citation: J Biol Chem. 2000 May 5;275(18):13755-8
references.pmid: 10788496
references.citation: Nat Struct Mol Biol. 2006 Feb;13(2):147-52
references.pmid: 16429154
references.citation: J Biol Chem. 1997 Dec 19;272(51):32158-62
references.pmid: 9405415
references.citation: Cell. 1996 Oct 18;87(2):241-51
references.pmid: 8861908
references.citation: Nature. 1999 Nov 11;402(6758):147-54
references.pmid: 10647006
references.citation: Crit Rev Biochem Mol Biol. 2006 Jul-Aug;41(4):211-39
references.pmid: 16849107
references.citation: J Biol Chem. 1986 Sep 15;261(26):12414-9
references.pmid: 3017973
references.citation: Structure. 1996 Jan 15;4(1):79-88
references.pmid: 8805508
references.citation: Science. 2002 Mar 8;295(5561):1852-8
references.pmid: 11884745
references.citation: J Biol Chem. 2002 Sep 6;277(36):33115-26
references.pmid: 12065585
references.citation: Nature. 1994 Oct 13;371(6498):578-86
references.pmid: 7935790
references.citation: Cell. 2000 Mar 3;100(5):561-73
references.pmid: 10721993
references.citation: Nature. 2009 Jan 1;457(7225):107-10
references.pmid: 19122642
references.citation: J Biol Chem. 2008 Aug 29;283(35):23931-9
references.pmid: 18583344
references.citation: Nature. 1994 Dec 15;372(6507):646-51
references.pmid: 7990955
references.citation: Cell. 1999 Apr 30;97(3):325-38
references.pmid: 10319813
references.citation: Nat Struct Biol. 1994 Jul;1(7):439-46
references.pmid: 7664062
references.citation: Curr Opin Struct Biol. 2005 Dec;15(6):646-51
references.pmid: 16249079
references.citation: Annu Rev Biochem. 1998;67:581-608
references.pmid: 9759498
references.citation: Anal Biochem. 1979 Nov 15;100(1):95-7
references.pmid: 161695
references.citation: Cell. 2005 Jul 29;122(2):209-20
references.pmid: 16051146
references.citation: J Mol Biol. 2003 Nov 28;334(3):489-99
references.pmid: 14623189
references.citation: Nat Struct Mol Biol. 2008 Mar;15(3):303-11
references.pmid: 18311152
references.citation: J Mol Biol. 1996 Jan 26;255(3):356-61
references.pmid: 8568880
references.citation: EMBO J. 1994 Jul 1;13(13):3192-202
references.pmid: 7913682
references.citation: Proc Natl Acad Sci U S A. 1989 Nov;86(21):8382-5
references.pmid: 2813394
references.citation: Annu Rev Biophys Biomol Struct. 2001;30:245-69
references.pmid: 11340060
references.citation: Nat Struct Biol. 1995 Dec;2(12):1083-94
references.pmid: 8846220
references.citation: Biochem Biophys Res Commun. 2000 Jan 27;267(3):842-9
references.pmid: 10673379
references.citation: Nature. 1994 Sep 15;371(6494):261-4
references.pmid: 7915827
references.citation: Chem Rev. 2006 May;106(5):1917-30
references.pmid: 16683761
references.citation: J Mol Biol. 1996 May 24;258(5):827-38
references.pmid: 8637013
references.citation: Cell. 2001 Dec 28;107(7):869-79
references.pmid: 11779463
references.citation: Cell. 1999 Dec 23;99(7):757-68
references.pmid: 10619429
references.citation: Biochemistry. 1993 Mar 16;32(10):2554-63
references.pmid: 8095403
references.citation: Proc Natl Acad Sci U S A. 1977 Jun;74(6):2236-40
references.pmid: 196283
references.citation: Nature. 1997 Aug 21;388(6644):741-50
references.pmid: 9285585
references.citation: Biochim Biophys Acta. 1992 Jun 24;1121(3):286-92
references.pmid: 1627606
references.citation: Nature. 1994 Oct 13;371(6498):614-9
references.pmid: 7935796
references.citation: Nat Struct Biol. 1996 Feb;3(2):170-7
references.pmid: 8564544
references.citation: Trends Biochem Sci. 2002 Dec;27(12):627-32
references.pmid: 12468232
references.citation: Proc Natl Acad Sci U S A. 1997 Apr 15;94(8):3571-5
references.pmid: 9108017
references.citation: J Mol Biol. 1999 Sep 10;292(1):181-90
references.pmid: 10493867