Conformational Mapping of Mini-B: An N-terminal/C-terminal Construct of Surfactant Protein B Using 13C-Enhanced Fourier Transform Infrared (FTIR) Spectroscopy

Experimental Data Snapshot


wwPDB Validation   3D Report Full Report

This is version 1.3 of the entry. See complete history


The role of charged amphipathic helices in the structure and function of surfactant protein B.

Waring, A.J.Walther, F.J.Gordon, L.M.Hernandez-Juviel, J.M.Hong, T.Sherman, M.A.Alonso, C.Alig, T.Braun, A.Bacon, D.Zasadzinski, J.A.

(2005) J Pept Res 66: 364-374

  • DOI: https://doi.org/10.1111/j.1399-3011.2005.00300.x
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 

    Surfactant protein B (SP-B) is essential for normal lung surfactant function. Theoretical models predict that the disulfide cross-linked, N- and C-terminal domains of SP-B fold as charged amphipathic helices, and suggest that these adjacent helices participate in critical surfactant activities. This hypothesis is tested using a disulfide-linked construct (Mini-B) based on the primary sequences of the N- and C-terminal domains. Consistent with theoretical predictions of the full-length protein, both isotope-enhanced Fourier transform infrared (FTIR) spectroscopy and molecular modeling confirm the presence of charged amphipathic alpha-helices in Mini-B. Similar to that observed with native SP-B, Mini-B in model surfactant lipid mixtures exhibits marked in vitro activity, with spread films showing near-zero minimum surface tensions during cycling using captive bubble surfactometry. In vivo, Mini-B shows oxygenation and dynamic compliance that compare favorably with that of full-length SP-B. Mini-B variants (i.e. reduced disulfides or cationic residues replaced by uncharged residues) or Mini-B fragments (i.e. unlinked N- and C-terminal domains) produced greatly attenuated in vivo and in vitro surfactant properties. Hence, the combination of structure and charge for the amphipathic alpha-helical N- and C-terminal domains are key to SP-B function.

  • Organizational Affiliation

    Department of Medicine, Division of Infectious Diseases, UCLA School of Medicine, Center for Health Sciences, Los Angeles, CA 90095, USA. awaring@ucla.edu

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Pulmonary surfactant-associated protein B34Homo sapiensMutation(s): 0 
Gene Names: SFTPBSFTP3
UniProt & NIH Common Fund Data Resources
Find proteins for P07988 (Homo sapiens)
Explore P07988 
Go to UniProtKB:  P07988
PHAROS:  P07988
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP07988
Sequence Annotations
  • Reference Sequence
Experimental Data & Validation

Experimental Data


Structure Validation

View Full Validation Report

Entry History 

Revision History  (Full details and data files)

  • Version 1.0: 2004-06-15
    Type: Initial release
  • Version 1.1: 2008-04-29
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2019-04-24
    Changes: Data collection, Experimental preparation, Refinement description, Source and taxonomy, Structure summary