Conformation of the abortifacient protein pinellin: a circular dichroic study.
The conformation of pinellin was studied by circular dichroism, which showed a minimum at 223 nm and a double maximum at 198-200 nm. The protein was rich in beta-sheet (about 40%) with little alpha-helix, based on current CD analyses. It was stable between pH4 and 10 beyond which it unfolded reversibly, but in alkaline solution, prolongly stored at, say, pH 12, it became irreversibly denatured. Thermal denaturation indicated a transition between 55 degrees and 68 degrees C; the solution at 80 degrees C was partially renatured upon air-cooling back to room temperature. Addition of sodium dodecyl sulfate caused a sharp increase in alpha-helix, which leveled off at 0.25 mM surfactant.
Tao
Z J
ZJ
Shanghai Brain Research Institute, Academia Sinica, China.
Shen
Z M
ZM
Yang
J T
JT
D000020:Abortifacient Agents, Nonsteroidal / Q000737:chemistry*; D000596:Amino Acids / Q000032:analysis; D002942:Circular Dichroism; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D037102:Lectins / Q000032:analysis / Q000737:chemistry* / Q000302:isolation & purification; D037121:Plant Lectins; D010940:Plant Proteins / Q000032:analysis / Q000737:chemistry* / Q000302:isolation & purification; D011487:Protein Conformation; D011489:Protein Denaturation; D012967:Sodium Dodecyl Sulfate / Q000494:pharmacology
D000020:Abortifacient Agents, Nonsteroidal; D000596:Amino Acids; D037102:Lectins; C047938:Pinellia ternata lectin; D037121:Plant Lectins; D010940:Plant Proteins; D012967:Sodium Dodecyl Sulfate