title: Role of the N-terminal seven residues of surfactant protein B (SP-B).
abstract: Breathing is enabled by lung surfactant, a mixture of proteins and lipids that forms a surface-active layer and reduces surface tension at the air-water interface in lungs. Surfactant protein B (SP-B) is an essential component of lung surfactant. In this study we probe the mechanism underlying the important functional contributions made by the N-terminal 7 residues of SP-B, a region sometimes called the "insertion sequence". These studies employed a construct of SP-B, SP-B (1-25,63-78), also called Super Mini-B, which is a 41-residue peptide with internal disulfide bonds comprising the N-terminal 7-residue insertion sequence and the N- and C-terminal helices of SP-B. Circular dichroism, solution NMR, and solid state (2)H NMR were used to study the structure of SP-B (1-25,63-78) and its interactions with phospholipid bilayers. Comparison of results for SP-B (8-25,63-78) and SP-B (1-25,63-78) demonstrates that the presence of the 7-residue insertion sequence induces substantial disorder near the centre of the lipid bilayer, but without a major disruption of the overall mechanical orientation of the bilayers. This observation suggests the insertion sequence is unlikely to penetrate deeply into the bilayer. The 7-residue insertion sequence substantially increases the solution NMR linewidths, most likely due to an increase in global dynamics.
authors.affiliation: Department of Biochemistry, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada.
authors.forename: Mahzad
authors.initials: M
authors.lastname: Sharifahmadian
authors.forename: Muzaddid
authors.initials: M
authors.lastname: Sarker
authors.forename: Dharamaraju
authors.initials: D
authors.lastname: Palleboina
authors.forename: Alan J
authors.initials: AJ
authors.lastname: Waring
authors.forename: Frans J
authors.initials: FJ
authors.lastname: Walther
authors.forename: Michael R
authors.initials: MR
authors.lastname: Morrow
authors.forename: Valerie
authors.initials: V
authors.lastname: Booth
mesh_terms: D000595:Amino Acid Sequence; D002942:Circular Dichroism; D009682:Magnetic Resonance Spectroscopy; D017433:Protein Structure, Secondary; D037701:Pulmonary Surfactant-Associated Protein B / Q000737:chemistry*
chemical_list: D037701:Pulmonary Surfactant-Associated Protein B
references.citation: Am J Physiol Lung Cell Mol Physiol. 2010 Mar;298(3):L335-47
references.pmid: 20023175
references.citation: Biochim Biophys Acta. 2008 Jul-Aug;1778(7-8):1676-95
references.pmid: 18515069
references.citation: J Magn Reson. 2009 Oct;200(2):296-302
references.pmid: 19666235
references.citation: Biochemistry. 1991 Nov 12;30(45):10965-71
references.pmid: 1932022
references.citation: Physiol Rev. 1995 Oct;75(4):749-57
references.pmid: 7480161
references.citation: Biochim Biophys Acta. 1998 Nov 19;1408(2-3):161-72
references.pmid: 9813304
references.citation: Pediatr Res. 1991 May;29(5):460-5
references.pmid: 1896249
references.citation: Chest. 2007 May;131(5):1577-82
references.pmid: 17494810
references.citation: Biopolymers. 2008 May;89(5):392-400
references.pmid: 17896349
references.citation: Monaldi Arch Chest Dis. 1995 Oct;50(5):372-7
references.pmid: 8541821
references.citation: Eur Biophys J. 2012 Sep;41(9):755-67
references.pmid: 22903196
references.citation: Biochim Biophys Acta. 1998 Nov 19;1408(2-3):79-89
references.pmid: 9813251
references.citation: Am Rev Respir Dis. 1988 Oct;138(4):990-8
references.pmid: 3059887
references.citation: Biochemistry. 2007 Oct 2;46(39):11047-56
references.pmid: 17845058
references.citation: Biochemistry. 1991 May 14;30(19):4687-96
references.pmid: 1709361
references.citation: Respir Physiol Neurobiol. 2010 Aug 31;173 Suppl:S55-64
references.pmid: 20206718
references.citation: Methods. 2004 Sep;34(1):121-32
references.pmid: 15283921
references.citation: Biophys J. 2010 Sep 22;99(6):1773-82
references.pmid: 20858421
references.citation: Biophys J. 2010 Oct 6;99(7):2134-42
references.pmid: 20923647
references.citation: Biochim Biophys Acta. 1998 Nov 19;1408(2-3):150-60
references.pmid: 9813296
references.citation: Biochim Biophys Acta. 2008 Oct;1778(10):1947-77
references.pmid: 18433715
references.citation: Biochim Biophys Acta. 1998 Nov 19;1408(2-3):278-89
references.pmid: 9813367
references.citation: Biophys J. 2000 Jul;79(1):377-84
references.pmid: 10866963
references.citation: Methods Enzymol. 2004;383:318-51
references.pmid: 15063656
references.citation: Biochemistry. 2003 Apr 15;42(14):4015-27
references.pmid: 12680754
references.citation: Comp Biochem Physiol A Mol Integr Physiol. 2001 May;129(1):287-94
references.pmid: 11369552
references.citation: J Pept Res. 2005 Dec;66(6):364-74
references.pmid: 16316452
references.citation: Biochem Mol Biol Int. 1996 Oct;40(3):617-27
references.pmid: 8908373
references.citation: J Lipid Res. 1995 Aug;36(8):1653-63
references.pmid: 7595087
references.citation: Biochemistry. 2002 Jul 30;41(30):9627-36
references.pmid: 12135384
references.citation: AMA J Dis Child. 1959 May;97(5, Part 1):517-23
references.pmid: 13649082
references.citation: PLoS One. 2010 Jan 13;5(1):e8672
references.pmid: 20084172
references.citation: J Appl Physiol Respir Environ Exerc Physiol. 1979 Sep;47(3):604-11
references.pmid: 583282
references.citation: Biochim Biophys Acta. 1983 Mar 21;737(1):117-71
references.pmid: 6337629
references.citation: Eur Biophys J. 2002 Mar;31(1):52-61
references.pmid: 12046897
references.citation: Biochim Biophys Acta. 1998 Nov 19;1408(2-3):109-31
references.pmid: 9813267
references.citation: Proc Soc Exp Biol Med. 1957 May;95(1):170-2
references.pmid: 13432025
references.citation: Proc Natl Acad Sci U S A. 1995 Aug 15;92(17):7794-8
references.pmid: 7644495
references.citation: Am J Physiol Regul Integr Comp Physiol. 2005 Nov;289(5):R1426-39
references.pmid: 16037124
references.citation: Respir Res. 2001;2(6):353-64
references.pmid: 11737935
references.citation: Biophys J. 2009 May 6;96(9):3762-71
references.pmid: 19413982
references.citation: Biochemistry. 2011 Jun 7;50(22):4867-76
references.pmid: 21553841
references.citation: Comp Biochem Physiol A Mol Integr Physiol. 2001 May;129(1):65-73
references.pmid: 11369534
references.citation: Protein Eng. 1993 Jun;6(4):383-90
references.pmid: 8332596
references.citation: J Clin Invest. 1994 Apr;93(4):1860-3
references.pmid: 8163685
references.citation: Biochemistry. 2004 Dec 7;43(48):15187-94
references.pmid: 15568810
references.citation: Adv Drug Deliv Rev. 2008 Mar 1;60(4-5):473-84
references.pmid: 18187229
references.citation: Clin Investig. 1993 Mar;71(3):177-90
references.pmid: 8481620
references.citation: Biophys J. 1989 Nov;56(5):1037-41
references.pmid: 2605294
references.citation: J Biol Chem. 1995 Jul 7;270(27):16225-9
references.pmid: 7608188
references.citation: N Engl J Med. 1994 May 26;330(21):1476-80
references.pmid: 8164699
references.citation: Semin Respir Crit Care Med. 2006 Aug;27(4):377-88
references.pmid: 16909371
references.citation: Biophys J. 2006 Jan 1;90(1):238-49
references.pmid: 16214863
references.citation: Biol Neonate. 2002;81 Suppl 1:6-15
references.pmid: 12011560
references.citation: Nature. 1955 Jun 25;175(4469):1125-6
references.pmid: 14394123
references.citation: Chem Phys Lipids. 1991 Dec;60(2):163-78
references.pmid: 1814640
references.citation: Biochimie. 2009 Jun;91(6):734-43
references.pmid: 19455745
references.citation: Biophys J. 2009 May 20;96(10):4085-98
references.pmid: 19450480
references.citation: Exp Lung Res. 2002 Dec;28(8):623-40
references.pmid: 12490037