Antifreeze protein (AFP) from Ammopiptanthus mongolicus leaves was isolated and purified with DEAE cellulose 52, Sephacryl 300, heat treatment and preparative isotachophoresis. The molecular weight of AFP was 50 ku by...Antifreeze protein (AFP) from Ammopiptanthus mongolicus leaves was isolated and purified with DEAE cellulose 52, Sephacryl 300, heat treatment and preparative isotachophoresis. The molecular weight of AFP was 50 ku by SDS-PAGE measurement. The average thermal hysteresis activity (THA) of AFP was 0.35℃ at 5 mg/mL using a differential scanning calorimeter (DSC). This AFP showed heated stability. From circular dichroism (CD) of AFP spectral data from 195-240 nm, a well-defined secondary structure of 11% a-helix, 34% antiparallel β-sheet and 55% random coil for the plant AFP was deduced.展开更多
Bifunctional molecules containing macrocyclic polyamine [12]aneN3 and carbazol units, 1-4, have been efficiently synthe sized and fully characterized. Through gel electrophoresis, atomic force microscopy, and dynamic ...Bifunctional molecules containing macrocyclic polyamine [12]aneN3 and carbazol units, 1-4, have been efficiently synthe sized and fully characterized. Through gel electrophoresis, atomic force microscopy, and dynamic light scattering experiments, compounds 3 and 4b bearing both [12]aneN3 and carbazol moieties showed effective DNA condensation ability at the concen- tration of 80 jaM. Investigations from EB displacement fluorescence spectra, viscosity titration, and ionic strength effects re vealed that the effective DNA condensation comes from the appropriate combination of carbazol and [12]aneN3 units in the bifunctional molecules, and the DNA condensation process is reversible. The incorporation of triazole units in the molecules clearly reduced the cytotoxicity.展开更多
基金the NationalNatural Science Foundation of China (Grant No. 39680025), the Foundation of Chinese Academy of Sciences and the Foundation of Special Subject of Study and Development of Transgenic Plant in China (Grant No. J99-A-019).
文摘Antifreeze protein (AFP) from Ammopiptanthus mongolicus leaves was isolated and purified with DEAE cellulose 52, Sephacryl 300, heat treatment and preparative isotachophoresis. The molecular weight of AFP was 50 ku by SDS-PAGE measurement. The average thermal hysteresis activity (THA) of AFP was 0.35℃ at 5 mg/mL using a differential scanning calorimeter (DSC). This AFP showed heated stability. From circular dichroism (CD) of AFP spectral data from 195-240 nm, a well-defined secondary structure of 11% a-helix, 34% antiparallel β-sheet and 55% random coil for the plant AFP was deduced.
基金supported by the Program for New Century Excellent Talents in Universities(NCET-08-0054)the National Natural Science Foundation of China(20972019)
文摘Bifunctional molecules containing macrocyclic polyamine [12]aneN3 and carbazol units, 1-4, have been efficiently synthe sized and fully characterized. Through gel electrophoresis, atomic force microscopy, and dynamic light scattering experiments, compounds 3 and 4b bearing both [12]aneN3 and carbazol moieties showed effective DNA condensation ability at the concen- tration of 80 jaM. Investigations from EB displacement fluorescence spectra, viscosity titration, and ionic strength effects re vealed that the effective DNA condensation comes from the appropriate combination of carbazol and [12]aneN3 units in the bifunctional molecules, and the DNA condensation process is reversible. The incorporation of triazole units in the molecules clearly reduced the cytotoxicity.
