Epiphragmin, the major protein of epiphragm mucus from the vineyard snail, Cernuella virgata.
The organic fraction of epiphragm mucus from the snail Cernuella virgata (Mollusca: Helicidae) consists predominantly of protein (17-23 dry wt.%) rather than carbohydrate (< or =0.4-2.0 dry wt.%), and the former underpins epiphragm membrane structure. The major protein ('epiphragmin') has an apparent molecular mass of approximately 86 kDa and is encoded by a cDNA (Genbank accession EF602752) which specifies a secreted protein of 81.2 kDa. The central region of the epiphragmin polypeptide is a coiled coil-forming region which is homologous to part of AglZ, a bacterial filament-forming protein. Coiled coil-driven self-assembly of epiphragmin probably underpins the formation of sheets in epiphragm membranes and the ability of epiphragm mucus to serve as an adhesive. The C-terminal region of epiphragmin is a fibrinogen-related domain (FReD) that is homologous to the fibrinogen-related proteins (FREPs) found in the hemolymph of freshwater snails. The material properties of epiphragm membranes resemble those of bovine ligament elastin. Wooden lap-joints bonded by rehydrated epiphragm fragments developed dry shear strength values of 1.4+/- 0.1 MPa.
Li
Dongmei
D
CSIRO Molecular & Health Technologies, Sydney Laboratory, P.O.Box 184, North Ryde, NSW 1670, Australia.
Graham
Lloyd D
LD
D000268:Adhesiveness; D000595:Amino Acid Sequence; D000818:Animals; D003001:Cloning, Molecular; D015180:Electrophoresis, Gel, Two-Dimensional; D004591:Electrophoresis, Polyacrylamide Gel; D015723:Gene Library; D008969:Molecular Sequence Data; D009093:Mucus / Q000737:chemistry*; D016133:Polymerase Chain Reaction; D011506:Proteins / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification; D012908:Snails / Q000235:genetics*; D027843:Vitis
D011506:Proteins