Protein Science, Vol 3, Issue 12 2217-2225, Copyright © 1994 by Cold Spring Harbor Laboratory Press

ARTICLE

Contributions of a hydrogen bond/salt bridge network to the stability of secondary and tertiary structure in {lambda} repressor

S. MARQUSEE and R. T. SAUER
Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139

In the N-terminal domain of {lambda} repressor, the Asp 14 side chain forms an intrahelical, hydrogen bond/salt bridge with the Arg 17 side chain and a tertiary hydrogen bond with the Ser 77 side chain. By measuring the stabilities to urea denaturation of the wild-type N-terminal domain and variants containing single, double, and triple ala-nine substitutions at positions 14, 17, and 77, the side-chain interaction energies, the coupling energy between interactions, and the intrinsic effects of each wild-type side chain on protein stability have been estimated. These studies indicate that the Asp 14-Arg 17 and Asp 14-Ser 77 interactions are stabilizing by roughly 0.8 and 1.5 kcal/mol, respectively, but that Asp 14, by itself, is destabilizing by roughly 0.9 kcal/mol. We also show that a peptide model of {alpha}-helix 1, which contains Asp 14 and Arg 17, forms a reasonably stable, monomeric helix in solution and responds to alanine mutations at positions 14 and 17 in the fashion expected from the intact protein studies. These studies suggest that it is possible to view the stability effects of mutations in intact proteins in a hierarchical fashion, with the stability of units of secondary structure being distinguishable from the stability of tertiary structure.
CiteULike    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				M. Ge, X.-Y. Xia, and X.-M. Pan Salt Bridges in the Hyperthermophilic Protein Ssh10b Are Resilient to Temperature Increases J. Biol. Chem., November 14, 2008; 283(46): 31690 - 31696. [Abstract] [Full Text] [PDF]

				A. G. Gvritishvili, A. V. Gribenko, and G. I. Makhatadze Cooperativity of complex salt bridges Protein Sci., July 1, 2008; 17(7): 1285 - 1290. [Abstract] [Full Text] [PDF]

				P. Chugha, H. J. Sage, and T. G. Oas Methionine oxidation of monomeric {lambda} repressor: The denatured state ensemble under nondenaturing conditions Protein Sci., March 1, 2006; 15(3): 533 - 542. [Abstract] [Full Text] [PDF]

				T. V. Pogorelov and Z. Luthey-Schulten Variations in the Fast Folding Rates of the {lambda}-Repressor: A Hybrid Molecular Dynamics Study Biophys. J., July 1, 2004; 87(1): 207 - 214. [Abstract] [Full Text] [PDF]

				S. Nishikori, K. Shiraki, K. Yokota, N. Izumikawa, S. Fujiwara, H. Hashimoto, T. Imanaka, and M. Takagi Mutational Effects on O6-Methylguanine-DNA Methyltransferase from Hyperthermophile: Contribution of Ion-Pair Network to Protein Thermostability J. Biochem., April 1, 2004; 135(4): 525 - 532. [Abstract] [Full Text] [PDF]

				D. D. Ojennus, S. E. Lehto, and D. S. Wuttke Electrostatic interactions in the reconstitution of an SH2 domain from constituent peptide fragments Protein Sci., January 1, 2003; 12(1): 44 - 55. [Abstract] [Full Text] [PDF]

				N. Sinha, S. Mohan, C. A. Lipschultz, and S. J. Smith-Gill Differences in Electrostatic Properties at Antibody-Antigen Binding Sites: Implications for Specificity and Cross-Reactivity Biophys. J., December 1, 2002; 83(6): 2946 - 2968. [Abstract] [Full Text] [PDF]

				O. Bogin, I. Levin, Y. Hacham, S. Tel-Or, M. Peretz, F. Frolow, and Y. Burstein Structural basis for the enhanced thermal stability of alcohol dehydrogenase mutants from the mesophilic bacterium Clostridium beijerinckii: contribution of salt bridging Protein Sci., November 1, 2002; 11(11): 2561 - 2574. [Abstract] [Full Text] [PDF]

				F. Dong and H.-X. Zhou Electrostatic Contributions to T4 Lysozyme Stability: Solvent-Exposed Charges versus Semi-Buried Salt Bridges Biophys. J., September 1, 2002; 83(3): 1341 - 1347. [Abstract] [Full Text] [PDF]

				S. Kumar and R. Nussinov Relationship between Ion Pair Geometries and Electrostatic Strengths in Proteins Biophys. J., September 1, 2002; 83(3): 1595 - 1612. [Abstract] [Full Text] [PDF]

				L. C. Roisman, J. Piehler, J.-Y. Trosset, H. A. Scheraga, and G. Schreiber Structure of the interferon-receptor complex determined by distance constraints from double-mutant cycles and flexible docking PNAS, November 6, 2001; 98(23): 13231 - 13236. [Abstract] [Full Text] [PDF]

				S.-i. Sakasegawa, H. Takehara, I. Yoshioka, M. Takahashi, Y. Kagimoto, H. Misaki, H. Sakuraba, and T. Ohshima Increasing the thermostability of Flavobacterium meningosepticum glycerol kinase by changing Ser329 to Asp in the subunit interface region Protein Eng. Des. Sel., September 1, 2001; 14(9): 663 - 667. [Abstract] [Full Text] [PDF]

				J. A. Hall, M.-C. Fann, and P. C. Maloney Altered Substrate Selectivity in a Mutant of an Intrahelical Salt Bridge in UhpT, the Sugar Phosphate Carrier of Escherichia coli J. Biol. Chem., March 5, 1999; 274(10): 6148 - 6153. [Abstract] [Full Text] [PDF]