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130 a.a.
Key reference
DOI no: 10.1006/jmbi.1993.1529 J Mol Biol 233:524-535 (1993) PubMed id: 8105095
Role of Arg115 in the catalytic action of human lysozyme. X-ray structure of His115 and Glu115 mutants. K.Harata, M.Muraki, Y.Jigami. ABSTRACT
The structure of modified human lysozymes (HLs), in which Arg115 is replaced by His or Glu, has been investigated by X-ray analysis at 1.77 A resolution. The mutation of the 115th residue by His does not affect the backbone structure as indicated by a root-mean-square deviation (r.m.s.d) of 0.14 A for the superposition of equivalent C alpha atoms between His115 HL and wild-type HL. In contrast, the corresponding r.m.s.d. value for Glu115 HL is 0.38 A which is twice as large as the estimated co-ordinate error of 0.2 A. Movement of the backbone structure is observed in the region of residues 100 to 130, which give an r.m.s.d. value of 0.61 A and a maximum deviation of 1.46 A for Arg119. A significant movement is also observed in the region of residues 45 to 50, which are located at the opposite side of the region of residues 100 to 120 with respect to the active site cleft. As a result, the active site cleft of Glu115 HL is narrower than the cleft of His115 HL or wild-type HL. This structural change is considered to be responsible for the low catalytic activity of Glu115 HL and the change of the catalytic property found in the hydrolysis of oligosaccharides. The replacement of Arg115 by Glu changes the charge distribution in the molecule, and the change in the electrostatic field may affect polar interactions among residues. The side-chain group of His115 and Glu115 is almost parallel to the indole moiety of Trp34, but the carboxyl group of Glu115 is laterally shifted to avoid overlapping with the indole moiety. The carboxylate anion of Glu115, which does not favor the face-to-face contact with aromatic groups, may provide a driving force for the structural change. The prominent structural change caused by the single mutation suggests that Arg115 is a key residue in maintaining the structure of the active site cleft.
Literature references that cite this PDB file's key reference
PubMed id Reference
18323666 S.Kawamura, Y.Chijiiwa, T.Minematsu, T.Fukamizo, K.M.Vårum, and T.Torikata (2008).
The role of Arg114 at subsites E and F in reactions catalyzed by hen egg-white lysozyme.Biosci Biotechnol Biochem, 72, 823-832.
17986339 J.H.Carra, C.A.McHugh, S.Mulligan, L.M.Machiesky, A.S.Soares, and C.B.Millard (2007).
Fragment-based identification of determinants of conformational and spectroscopic change at the ricin active site.BMC Struct Biol, 7, 72.
PDB codes: 2p8n 2pjn 2pjo 2r2x 2r3d
16909420 L.Mazzarella, A.Vergara, L.Vitagliano, A.Merlino, G.Bonomi, S.Scala, C.Verde, and G.di Prisco (2006).
High resolution crystal structure of deoxy hemoglobin from Trematomus bernacchii at different pH values: the role of histidine residues in modulating the strength of the root effect.Proteins, 65, 490-498.
PDB codes: 2h8d 2h8f 9385633 A.C.Wallace, N.Borkakoti, and J.M.Thornton (1997).
TESS: a geometric hashing algorithm for deriving 3D coordinate templates for searching structural databases. Application to enzyme active sites.Protein Sci, 6, 2308-2323. 8535242 P.Shih, and J.F.Kirsch (1995).
Design and structural analysis of an engineered thermostable chicken lysozyme.Protein Sci, 4, 2063-2072. The most recent references are shown first. Citation data come partly from CiteXplore and partly from an automated harvesting procedure. Note that this is likely to be only a partial list as not all journals are covered by either method. However, we are continually building up the citation data so more and more references will be included with time. Where a reference describes a PDB structure, the PDB codes are shown on the right.
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