Related Experiment Videos
Three-dimensional solution structure of apo-neocarzinostatin
1Structural and Biophysical Chemistry, Glaxo Inc. Research Institute, Research Triangle Park, NC 27709.
Journal of Molecular Biology
|May 5, 1992
Summary
High-resolution structures of the neocarzinostatin (NCS) apoprotein were determined using nuclear magnetic resonance and molecular dynamics. This reveals a beta-barrel structure crucial for binding the antitumor chromophore.
Area of Science:
- Structural Biology
- Biochemistry
- Molecular Biophysics
Background:
- Neocarzinostatin (NCS) is a natural antitumor agent comprising an apoprotein and a chromophore.
- Understanding the apoprotein's structure is key to elucidating the drug's mechanism of action.
Purpose of the Study:
- To determine the high-resolution three-dimensional solution structure of the 11K apoprotein from neocarzinostatin (apo-NCS).
- To identify structural features responsible for binding the NCS chromophore.
Main Methods:
- Two- and three-dimensional nuclear magnetic resonance (NMR) spectroscopy.
- Restrained molecular dynamics (MD) computations with iterative refinement.
Main Results:
- The solution structure of apo-NCS features seven antiparallel beta-strands forming a beta-barrel, lacking alpha-helical components.
- A cavity formed by specific beta-strands constitutes the chromophore-binding site.
- Structural similarities and differences in binding cavities were noted compared to analogous proteins like apoauromomycin.
Conclusions:
- The determined beta-barrel structure provides a structural basis for the specific recognition and binding of the antitumor NCS chromophore.
- This structural insight aids in understanding the molecular mechanism of neocarzinostatin's biological activity.