Pancreatic spasmolytic polypeptide: first three-dimensional structure of a member of the mammalian trefoil family of peptides.
BACKGROUND
The trefoil peptides are a rapidly growing family of peptides, mainly found in the gastrointestinal tract. There is circumstantial evidence that they stabilize the mucus layer, and may affect the rate of healing of the mucosal epithelium.


RESULTS
We have determined the structure of porcine pancreatic spasmolytic polypeptide (PSP) to 2.5 A resolution. The polypeptide contains two trefoil domains. The domain structure is compact, and is composed of a central short antiparallel beta-sheet with one short helix above and one below it. This is a novel motif. The two domains are related by two-fold symmetry, and each domain contains a cleft.


CONCLUSIONS
The cleft within each domain could accommodate a polysaccharide chain, and may therefore be responsible for binding mucin glycoproteins. We suggest that PSP may cross-link glycoproteins, explaining its ability to stabilize the mucus layer.
Gajhede
M
M
Department of Chemistry, H.C. Orsted Institute, University of Copenhagen, Denmark.
Petersen
T N
TN
Henriksen
A
A
Petersen
J F
JF
Dauter
Z
Z
Wilson
K S
KS
Thim
L
L
D000595:Amino Acid Sequence; D000818:Animals; D018360:Crystallography, X-Ray / Q000379:methods; D004064:Digestive System; D006860:Hydrogen Bonding; D036341:Intercellular Signaling Peptides and Proteins; D008322:Mammals; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009077:Mucins; D009124:Muscle Proteins; D009479:Neuropeptides; D010455:Peptides / Q000737:chemistry*; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D017386:Sequence Homology, Amino Acid; D013552:Swine; D013565:Sympatholytics; D000071164:Trefoil Factor-2; D000071165:Trefoil Factor-3
D036341:Intercellular Signaling Peptides and Proteins; D009077:Mucins; D009124:Muscle Proteins; D009479:Neuropeptides; D010455:Peptides; D013565:Sympatholytics; C099037:TFF3 protein, rat; C000604008:Tff2 protein, rat; D000071164:Trefoil Factor-2; D000071165:Trefoil Factor-3; C034407:pancreatic spasmolytic polypeptide