PDBsum entry 1kmr

Lipid binding protein

PDB id: 1kmr

Contents

Protein chain

15 a.a.

PDB id:

1kmr

Name:

Lipid binding protein

Title:

Solution nmr structure of surfactant protein b (11-25) (sp-b11-25)

Structure:

Pulmonary surfactant-associated protein b. Chain: a. Fragment: sequence database residues 211-225, numbered 11-25. Synonym: sp-b, pulmonary surfactant-associated proteolipid spl(phe), 18 kda pulmonary-surfactant protein. Engineered: yes

Source:

Synthetic: yes. Other_details: the protein was chemically synthesized. The sequence of the protein is naturally found in homo sapiens (humans).

NMR struc:

17 models

Authors:

J.W.Kurutz,K.Y.C.Lee

Key ref:

J.W.Kurutz and K.Y.Lee (2002). NMR structure of lung surfactant peptide SP-B(11-25). Biochemistry, 41, 9627-9636. PubMed id: 12135384 DOI: 10.1021/bi016077x

Date:

17-Dec-01 Release date: 07-Aug-02

Protein chain

P07988  (PSPB_HUMAN) -  Pulmonary surfactant-associated protein B from Homo sapiens

Seq: 381 a.a.

Struc: 15 a.a.

Enzyme reactions

• Enzyme class: E.C.?

DOI no: 10.1021/bi016077x

Biochemistry 41:9627-9636 (2002)

PubMed id: 12135384

NMR structure of lung surfactant peptide SP-B(11-25).

J.W.Kurutz, K.Y.Lee.

ABSTRACT

Surfactant protein B (SP-B) is a 79-residue essential component of lung surfactant, the film of lipid and protein lining the alveoli, and is the subject of great interest for its role in lung surfactant replacement therapies. Here we report circular dichroism results and the solution NMR structure of SP-B(11-25) (CRALIKRIQAMIPKG) dissolved in CD(3)OH at 5 degrees C. This is the first report of NMR data related to the protein SP-B, whose structure promises to help elucidate the mechanism of its function. Sequence-specific resonance assignments were made for all observable (1)H NMR signals on the basis of standard 2D NMR methods. Structures were determined by the simulated annealing method using restraints derived from 2D NOESY data. The calculations yielded 17 energy-minimized structures, three of which were subjected to 0.95 ns of restrained dynamics to assess the relevance of the static structures to more realistic dynamic behavior. Our CD and NMR data confirm that this segment is an amphiphilic alpha helix from approximately residue L14 through M21. The backbone heavy-atom RMSD for residues L14 through M21 is 0.09 +/- 0.12 A, and the backbone heavy-atom RMSD for the whole peptide is 0.96 +/- 2.45 A, the difference reflecting fraying at the termini. Aside from the disordered termini, the minimized structures represent dynamic structures well. Structural similarity to the homologous regions of related saposin-like proteins and the importance of the distribution of polar residues about the helix axis are discussed.