Palme, Stefan and Jaenicke, Rainer and Slingsby, Christine (1998) X-ray structures of three interface mutants of gamma B-crystallin from bovine eye lens. PROTEIN SCIENCE, 7 (3). pp. 611-618. ISSN 0961-8368, 1469-896X
Full text not available from this repository.Abstract
gamma B-crystallin consists of two domains each comprising two "Greek key" motifs. Both domains fold independently, and domain interactions contribute significantly to the stability of the C-terminal domain. In a previous study (Palme S et al., 1996, Protein Sci 6:1529-1636) it was shown that Phe56 from the N-terminal domain, a residue involved in forming a hydrophobic core at the domain interface, effects the interaction of the two domains, and therefore, the stability of the C-terminal domain. Ala or Asp at position 56 drastically decreased the stability of the C-terminal domain, whereas Trp had a more moderate effect. In this article we present the X-ray structures of these interface mutants and correlate them with the stability data. The mutations do not effect the overall structure of the molecule. No structural changes are observed in the vicinity of the replaced residue, suggesting that the local structure is too rigid to allow compensations for the amino acid replacements. In the mutants gamma B-F56A and -F56D, a solvent-filled groove accessible to the bulk solvent is created by the replacement of the bulky Phe side chain. In gamma B-F56W, the pyrrole moiety of the indole ring replaces the phenyl side chain of the wild type. With the exception of gamma B-F56W there is a good correlation between the hydrophobicity of the amino acid at position 56 according to the octanol scale and the stability of the C-terminal domain. In gamma B-F56W, the C-terminal domain is less stable than estimated from the hydrophobicity, presumably because the ring nitrogen (N epsilon 1) has no partner to form hydrogen bonds. The data suggest that the packing of hydrophobic residues in the interface core is important for domain interactions and the stability of gamma B-crystallin. Apparently, for protein stability, the same principles apply for hydrophobic cores within domains and at domain interfaces.
| Item Type: | Article |
|---|---|
| Uncontrolled Keywords: | CAVITY-CREATING MUTATIONS; PROTEIN STRUCTURES; HYDROPHOBIC CORE; T4 LYSOZYME; STABILITY; EVOLUTION; ACCESSIBILITY; ASSOCIATION; BARNASE; CELL; domain interaction, hydrophobic effect; protein stability; site-directed mutagenesis; X-ray crystallography |
| Subjects: | 500 Science > 540 Chemistry & allied sciences 500 Science > 570 Life sciences |
| Divisions: | Biology, Preclinical Medicine > Institut für Biophysik und physikalische Biochemie |
| Depositing User: | Dr. Gernot Deinzer |
| Date Deposited: | 28 Mar 2023 04:27 |
| Last Modified: | 28 Mar 2023 04:27 |
| URI: | https://pred.uni-regensburg.de/id/eprint/50069 |
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