2001
Comparative binding energy (COMBINE) analysis of the substrate specificity of haloalkane dehalogenase from Xanthobacter autotrophicus GJ10
KMUNÍČEK, Jan; Santos LUENGO; Federico GAGO; Angel Ramirez ORTIZ; Rebecca WADE et al.Základní údaje
Originální název
Comparative binding energy (COMBINE) analysis of the substrate specificity of haloalkane dehalogenase from Xanthobacter autotrophicus GJ10
Autoři
KMUNÍČEK, Jan; Santos LUENGO; Federico GAGO; Angel Ramirez ORTIZ; Rebecca WADE a Jiří DAMBORSKÝ
Vydání
Biochemistry, 2001, 0006-2960
Další údaje
Jazyk
angličtina
Typ výsledku
Článek v odborném periodiku
Obor
10600 1.6 Biological sciences
Stát vydavatele
Spojené státy
Utajení
není předmětem státního či obchodního tajemství
Odkazy
Impakt faktor
Impact factor: 4.114
Označené pro přenos do RIV
Ano
Kód RIV
RIV/00216224:14310/01:00004531
Organizační jednotka
Přírodovědecká fakulta
Změněno: 15. 12. 2006 11:21, Mgr. Jan Kmuníček, Ph.D.
Anotace
V originále
Comparative binding energy (COMBINE) analysis was conducted for eighteen substrates of the haloalkane dehalogenase from Xanthobacter autotrophicus GJ10: 1-chlorobutane; 1-chlorohexane; dichloromethane; 1,2-dichloroethane; 1,2-dichloropropane; 2-chloroethanol; epichlorohydrine; 2-chloroacetonitrile, 2-chloroacetamide and their brominated analogs. The purpose of the COMBINE analysis was to identify the amino acid residues determining the substrate specificity of the haloalkane dehalogenase. This knowledge is essential for the tailoring of this enzyme for biotechnological applications. Complexes of the enzyme with these substrates were modeled and then refined by molecular mechanics energy minimization. The intermolecular enzyme-substrate energy was decomposed into residue-wise van der Waals and electrostatic contributions and complemented by surface area dependent and electrostatic desolvation terms. Partial least-squares projection to latent structures analysis was then used to establish relationships between the energy contributions and the experimental apparent dissociation constants. A model containing van der Waals and electrostatic intermolecular interaction energy contributions calculated using the AMBER force field explained 91 % (73 % cross-validated) of the quantitative variance in the apparent dissociation constants. A model based on van der Waals intermolecular contributions from AMBER and electrostatic interactions derived from the Poisson-Boltzmann equation explained 93 % (74 % cross-validated) of the quantitative variance. COMBINE models predicted correctly the change in apparent dissociation constants upon single-point mutation of DhlA for six enzyme-substrate complexes. The amino acid residues contributing most significantly to the substrate specificity of DhlA were identified; they include Asp124, Trp125, Phe164, Phe172, Trp175, Phe222, Pro223 and Leu263. These residues are suitable targets for modification by site-directed mutagenesis.
Návaznosti
| LN00A016, projekt VaV |
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