Abstract
By using oligonucleotide-directed mutagenesis, Lys-112 of bovine growth hormone (bGH) was changed to leucine, and its resulting effect on folding was studied. Equilibrium denaturation curves for the mutant protein exhibit biphasic or nonsymmetrical transitions by a variety of spectroscopic and hydrodynamic techniques, whereas the wild-type protein at the same concentration exhibits symmetrical transitions. The mutant protein refolds slower (by a factor of 30) and more readily precipitates upon refolding than the wild-type protein. These folding characteristics of the mutant protein are demonstrated to be a result of stabilization of an associated folding intermediate. A 38-amino acid fragment (96-133) derived from the mutant protein is helical, likely amphipathic, and more stabilized by increasing peptide concentration than is the corresponding helical peptide from the wild-type protein. The increased stability of the associated intermediate and the increased helicity of the peptide from the mutant protein are explained by preferential intermolecular interactions between helices due to enhanced hydrophobic attraction by their amphipathic surfaces.
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Selected References
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- Abdel-Meguid S. S., Shieh H. S., Smith W. W., Dayringer H. E., Violand B. N., Bentle L. A. Three-dimensional structure of a genetically engineered variant of porcine growth hormone. Proc Natl Acad Sci U S A. 1987 Sep;84(18):6434–6437. doi: 10.1073/pnas.84.18.6434. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Brems D. N., Plaisted S. M., Dougherty J. J., Jr, Holzman T. F. The kinetics of bovine growth hormone folding are consistent with a framework model. J Biol Chem. 1987 Feb 25;262(6):2590–2596. [PubMed] [Google Scholar]
- Brems D. N., Plaisted S. M., Havel H. A., Kauffman E. W., Stodola J. D., Eaton L. C., White R. D. Equilibrium denaturation of pituitary- and recombinant-derived bovine growth hormone. Biochemistry. 1985 Dec 17;24(26):7662–7668. doi: 10.1021/bi00347a025. [DOI] [PubMed] [Google Scholar]
- Brems D. N., Plaisted S. M., Kauffman E. W., Havel H. A. Characterization of an associated equilibrium folding intermediate of bovine growth hormone. Biochemistry. 1986 Oct 21;25(21):6539–6543. doi: 10.1021/bi00369a030. [DOI] [PubMed] [Google Scholar]
- Brems D. N., Plaisted S. M., Kauffman E. W., Lund M., Lehrman S. R. Helical formation in isolated fragments of bovine growth hormone. Biochemistry. 1987 Dec 1;26(24):7774–7778. doi: 10.1021/bi00398a036. [DOI] [PubMed] [Google Scholar]
- Burger H. G., Edelhoch H., Condliffe P. G. The properties of bovine growth hormone. I. Behavior in acid solution. J Biol Chem. 1966 Jan 25;241(2):449–457. [PubMed] [Google Scholar]
- Gráf L., Li C. H. Isolation and properties of two biologically active fragments from limited tryptic hydrolysis of bovine and ovine pituitary growth hormones. Biochemistry. 1974 Dec 17;13(26):5408–5415. doi: 10.1021/bi00723a026. [DOI] [PubMed] [Google Scholar]
- Hartman P. A., Stodola J. D., Harbour G. C., Hoogerheide J. G. Reversed-phase high-performance liquid chromatography peptide mapping of bovine somatotropin. J Chromatogr. 1986 Jun 25;360(2):385–395. doi: 10.1016/s0021-9673(00)91687-x. [DOI] [PubMed] [Google Scholar]
- Havel H. A., Kauffman E. W., Plaisted S. M., Brems D. N. Reversible self-association of bovine growth hormone during equilibrium unfolding. Biochemistry. 1986 Oct 21;25(21):6533–6538. doi: 10.1021/bi00369a029. [DOI] [PubMed] [Google Scholar]
- ROSEN H. A modified ninhydrin colorimetric analysis for amino acids. Arch Biochem Biophys. 1957 Mar;67(1):10–15. doi: 10.1016/0003-9861(57)90241-2. [DOI] [PubMed] [Google Scholar]
- Schold M., Colombero A., Reyes A. A., Wallace R. B. Oligonucleotide-directed mutagenesis using plasmid DNA templates and two primers. DNA. 1984 Dec;3(6):469–477. doi: 10.1089/dna.1.1984.3.469. [DOI] [PubMed] [Google Scholar]
- Uhlin B. E., Nordström K. A runaway-replication mutant of plasmid R1drd-19: temperature-dependent loss of copy number control. Mol Gen Genet. 1978 Oct 4;165(2):167–179. doi: 10.1007/BF00269904. [DOI] [PubMed] [Google Scholar]
- Wallace R. B., Johnson M. J., Suggs S. V., Miyoshi K., Bhatt R., Itakura K. A set of synthetic oligodeoxyribonucleotide primers for DNA sequencing in the plasmid vector pBR322. Gene. 1981 Dec;16(1-3):21–26. doi: 10.1016/0378-1119(81)90057-3. [DOI] [PubMed] [Google Scholar]