title: Protein stabilization by hydrophobic interactions at the surface.
abstract: The contribution of the solvent-exposed residue 63 to thermal stability of the thermolysin-like neutral protease of Bacillus stearothermophilus was studied by analyzing the effect of twelve different amino acid substitutions at this position. The thermal stability of the enzyme was increased considerably by introducing Arg, Lys or bulky hydrophobic amino acids. In general, the effects of the mutations showed that hydrophobic contacts in this surface-located region of the protein are a major determinant of thermal stability. This observation contrasts with general concepts concerning the contribution of surface-located residues and surface hydrophobicity to protein stability and indicates new ways for protein stabilization by site-directed mutagenesis.
authors.affiliation: Department of Genetics, University of Groningen, Haren, The Netherlands.
authors.forename: B
authors.initials: B
authors.lastname: Van den Burg
authors.forename: B W
authors.initials: BW
authors.lastname: Dijkstra
authors.forename: G
authors.initials: G
authors.lastname: Vriend
authors.forename: B
authors.initials: B
authors.lastname: Van der Vinne
authors.forename: G
authors.initials: G
authors.lastname: Venema
authors.forename: V G
authors.initials: VG
authors.lastname: Eijsink
mesh_terms: D001426:Bacterial Proteins; D010450:Endopeptidases / Q000737:chemistry*; D001411:Geobacillus stearothermophilus / Q000201:enzymology*; D006358:Hot Temperature; D006860:Hydrogen Bonding; D008666:Metalloendopeptidases / Q000737:chemistry; D011489:Protein Denaturation; D017434:Protein Structure, Tertiary; D012995:Solubility; D013329:Structure-Activity Relationship; D013499:Surface Properties; D013820:Thermolysin / Q000737:chemistry
chemical_list: D001426:Bacterial Proteins; D010450:Endopeptidases; D008666:Metalloendopeptidases; D013820:Thermolysin; C065625:neutral protease, Bacillus stearothermophilus