title: A synthetic S6 segment derived from KvAP channel self-assembles, permeabilizes lipid vesicles, and exhibits ion channel activity in bilayer lipid membrane.
abstract: KvAP is a voltage-gated tetrameric K(+) channel with six transmembrane (S1-S6) segments in each monomer from the archaeon Aeropyrum pernix. The objective of the present investigation was to understand the plausible role of the S6 segment, which has been proposed to form the inner lining of the pore, in the membrane assembly and functional properties of KvAP channel. For this purpose, a 22-residue peptide, corresponding to the S6 transmembrane segment of KvAP (amino acids 218-239), and a scrambled peptide (S6-SCR) with rearrangement of only hydrophobic amino acids but without changing its composition were synthesized and characterized structurally and functionally. Although both peptides bound to the negatively charged phosphatidylcholine/phosphatidylglycerol model membrane with comparable affinity, significant differences were observed between these peptides in their localization, self-assembly, and aggregation properties onto this membrane. S6-SCR also exhibited reduced helical structures in SDS micelles and phosphatidylcholine/phosphatidylglycerol lipid vesicles as compared with the S6 peptide. Furthermore, the S6 peptide showed significant membrane-permeabilizing capability as evidenced by the release of calcein from the calcein-entrapped lipid vesicles, whereas S6-SCR showed much weaker efficacy. Interestingly, although the S6 peptide showed ion channel activity in the bilayer lipid membrane, despite having the same amino acid composition, S6-SCR was significantly inactive. The results demonstrated sequence-specific structural and functional properties of the S6 wild type peptide. The selected S6 segment is probably an important structural element that could play an important role in the membrane interaction, membrane assembly, and functional property of the KvAP channel.
authors: Molecular and Structural Biology Division, Central Drug Research Institute, Council of Scientific and Industrial Research, Chattar Manzil Palace, Lucknow 226001, India.
authors: Richa
authors: R
authors: Verma
authors: Chetan
authors: C
authors: Malik
authors: Sarfuddin
authors: S
authors: Azmi
authors: Saurabh
authors: S
authors: Srivastava
authors: Subhendu
authors: S
authors: Ghosh
authors: Jimut Kanti
authors: JK
authors: Ghosh
references: J Biol Chem. 1993 Jul 15;268(20):14601-7
references: 7686900
references: Biophys J. 1997 Aug;73(2):831-8
references: 9251799
references: Biochemistry. 1993 Nov 23;32(46):12363-71
references: 8241124
references: J Pept Sci. 2009 Sep;15(9):601-6
references: 19606426
references: Biochim Biophys Acta. 2007 Jun;1768(6):1574-82
references: 17467657
references: PLoS Biol. 2010 Feb 23;8(2):e1000315
references: 20208975
references: Biochim Biophys Acta. 1986 Sep 25;861(1):141-51
references: 3756150
references: FEBS Lett. 1990 Jan 1;259(2):254-6
references: 2136730
references: J Mol Biol. 2002 Jan 4;315(1):63-72
references: 11771966
references: Biochemistry. 1969 Oct;8(10):4108-16
references: 5346390
references: Biochim Biophys Acta. 1989 Feb 13;979(1):82-90
references: 2917170
references: Protein Eng. 1994 Feb;7(2):255-62
references: 8170928
references: J Biol Chem. 2001 Sep 21;276(38):35714-22
references: 11473117
references: Biochemistry. 1993 Apr 6;32(13):3429-36
references: 8384882
references: J Gen Physiol. 2002 Jul;120(1):87-97
references: 12084778
references: J Pept Res. 2001 Jan;57(1):39-47
references: 11168887
references: Annu Rev Cell Dev Biol. 2006;22:23-52
references: 16704338
references: Biochemistry. 2009 Nov 24;48(46):10905-17
references: 19845398
references: Science. 1988 May 27;240(4856):1177-81
references: 2453923
references: Protein Sci. 1995 Aug;4(8):1490-7
references: 8520474
references: Biochem J. 2011 Jun 15;436(3):609-20
references: 21434868
references: Methods Enzymol. 1992;207:510-25
references: 1382200
references: Biochemistry. 1987 May 19;26(10):2751-9
references: 3606990
references: Nature. 1994 Jan 13;367(6459):179-82
references: 8114915
references: Neurotherapeutics. 2007 Apr;4(2):184-98
references: 17395128
references: Neuroscience. 1988 Jun;25(3):729-49
references: 2457185
references: Biochemistry. 1996 May 28;35(21):6828-38
references: 8639634
references: Biochemistry. 1990 Jan 9;29(1):52-8
references: 2322549
references: J Gen Physiol. 2005 Nov;126(5):413-7
references: 16260835
references: Biochemistry. 1993 Mar 9;32(9):2371-7
references: 8443177
references: J Biol Chem. 1994 May 13;269(19):13867-73
references: 8188663
references: Nature. 2003 Mar 13;422(6928):180-5
references: 12629550
references: Biochemistry. 1989 Apr 18;28(8):3168-76
references: 2742832
references: Biophys J. 1994 Apr;66(4):1061-7
references: 8038378
references: Proc Natl Acad Sci U S A. 2005 Oct 25;102(43):15441-6
references: 16223877
references: Proc Natl Acad Sci U S A. 1992 Nov 1;89(21):10537-41
references: 1438243
references: Proc Natl Acad Sci U S A. 1990 Jan;87(1):210-4
references: 1688654
references: Biochemistry. 1990 May 1;29(17):4031-7
references: 1694455
references: Biochim Biophys Acta. 1982 Apr 7;686(2):204-14
references: 7082663
references: Nature. 2002 May 30;417(6888):523-6
references: 12037560
references: Science. 1991 Feb 22;251(4996):939-42
references: 2000494
references: J Membr Biol. 1978 Sep 19;42(3):265-79
references: 359814
references: Physiol Rev. 1992 Oct;72(4 Suppl):S69-88
references: 1438587
references: Neuron. 1998 Mar;20(3):371-80
references: 9539115
references: Biophys J. 1996 Jun;70(6):2502-12
references: 8744290
references: Biochim Biophys Acta. 1980 Apr 10;597(2):418-26
references: 7370258
references: J Biol Chem. 2004 Nov 26;279(48):50601-8
references: 15355961
references: J Biol Chem. 1991 Dec 15;266(35):23769-75
references: 1748653
references: Biochemistry. 1978 Nov 28;17(24):5241-8
references: 728398
references: J Biol Chem. 1993 Jul 15;268(20):14608-15
references: 7686901
references: Science. 1991 Feb 22;251(4996):942-4
references: 2000495
references: Int J Pept Protein Res. 1994 Jun;43(6):597-607
references: 7523324
references: Biochemistry. 1997 Dec 9;36(49):15451-62
references: 9398274
references: Biophys J. 2003 Jan;84(1):295-305
references: 12524283
references: Biochemistry. 1998 Mar 10;37(10):3229-36
references: 9536962
references: Proc Natl Acad Sci U S A. 1994 Feb 15;91(4):1495-9
references: 7509074
references: Anal Sci. 2007 May;23(5):517-22
references: 17495394
references: Biophys J. 2010 Mar 3;98(5):762-72
references: 20197029
references: Nat Rev Neurosci. 2002 Feb;3(2):115-21
references: 11836519
references: J Biol Chem. 1998 Oct 16;273(42):27182-90
references: 9765238
references: Nature. 2003 May 1;423(6935):33-41
references: 12721618
references: Science. 1977 Jun 17;196(4296):1341-2
references: 867034
references: Biophys J. 1987 Nov;52(5):685-92
references: 3427183
references: J Mol Biol. 2009 Jul 31;390(5):902-12
references: 19481093
references: Anal Biochem. 1970 Apr;34(2):595-8
references: 5443684
references: Biochemistry. 1971 Nov 23;10(24):4433-40
references: 4946923
references: Biochemistry. 1981 Feb 3;20(3):566-70
references: 6111337
references: J Biol Chem. 2006 Dec 1;281(48):37057-68
references: 17032656
references: J Biol Chem. 1995 Dec 15;270(50):29910-5
references: 8530389
references: Curr Opin Struct Biol. 2000 Aug;10(4):456-61
references: 10981635
references: Proc Natl Acad Sci U S A. 1999 Jul 6;96(14):7910-5
references: 10393921
references: Annu Rev Neurosci. 1997;20:91-123
references: 9056709
references: Biochim Biophys Acta. 2009 Feb;1788(2):538-50
references: 19111524
references: J Gen Physiol. 1998 Aug;112(2):243-57
references: 9689030
references: J Biol Chem. 1959 Mar;234(3):466-8
references: 13641241
references: Biochim Biophys Acta. 2010 Mar;1798(3):461-70
references: 20044973
references: Int J Pept Protein Res. 1990 Mar;35(3):161-214
references: 2191922
references: Nat Rev Drug Discov. 2009 Feb;8(2):153-71
references: 19153558
references: Trends Pharmacol Sci. 1992 Sep;13(9):359-65
references: 1382336
references: Science. 2003 Jun 20;300(5627):1922-6
references: 12738871
references: Br J Pharmacol. 2006 Jan;147 Suppl 1:S63-71
references: 16402122
references: Annu Rev Physiol. 1992;54:537-55
references: 1562183
references: Biochemistry. 1994 Jan 11;33(1):283-90
references: 7506930
references: Angew Chem Int Ed Engl. 2003 Dec 1;42(46):5671-5
references: 14661197
references: Cell Death Differ. 2005 Aug;12(8):1134-40
references: 15861186
references: Proc Natl Acad Sci U S A. 1989 Jan;86(2):707-10
references: 2536173
references: Biochem Biophys Res Commun. 1994 Jan 28;198(2):445-50
references: 8297354
references: J Gen Physiol. 1999 Oct;114(4):551-60
references: 10498673
references: Biochem Biophys Res Commun. 2005 May 6;330(2):585-90
references: 15796923
references: Nature. 1994 Sep 8;371(6493):119-22
references: 8072541
references: J Biol Chem. 2000 Aug 4;275(31):23602-7
references: 10811807
references: Neuron. 2005 Dec 8;48(5):719-25
references: 16337910
references: Biochemistry. 1987 Jan 13;26(1):39-45
references: 3030403
references: J Biol Chem. 1991 Nov 25;266(33):22346-54
references: 1939258
references: Q Rev Biophys. 1994 May;27(2):157-218
references: 7984776
references: Biochemistry. 1990 Dec 11;29(49):10995-1000
references: 2271694
references: J Biol Chem. 1994 Sep 30;269(39):23904-10
references: 7929037
references: Am J Physiol Cell Physiol. 2002 Jan;282(1):C161-71
references: 11742809
references: J Biol Chem. 1998 Apr 10;273(15):9312-22
references: 9535926
references: J Physiol. 1952 Aug;117(4):500-44
references: 12991237
references: J Biol Chem. 2003 Dec 19;278(51):51023-34
references: 14525984
references: J Gen Physiol. 2002 Jun;119(6):521-32
references: 12034760
references: Nature. 2004 Apr 22;428(6985):864-8
references: 15103379
references: Science. 1998 Apr 3;280(5360):69-77
references: 9525859
references: J Neurochem. 2006 Aug;98(3):670-6
references: 16787424
references: Proc Natl Acad Sci U S A. 1988 Apr;85(7):2393-7
references: 2451248