Haloacid dehalogenases

This is an emerging field that has not reached its final position yet. Members of the novel class of FCP, SCP, and HAD phosphatases require Mg2+ for catalysis. An aspartate residue within the active site signature motif (DxDx(T/V)) is essential to form an acyl-phosphate intermediate. Many members of the the HAD (haloacid dehalogenase) superfamily have phosphoesterase activity [3]. Some of those protein phosphatases act on... 

Li Y-F, Y Hata, T Fujii, T Hisano, M Nishihara, T Kurihara, N Esaki (1998) Crystal structures of reaction intermediates of L-2-haloacid dehalogenase and implications for the reaction mechanism. J Biol Chem 273 15035-15044. 

Nardi-Del V T, C Kutihara, C Park, N Esaki, K Soda (1997) Bacterial DL-2-haloacid dehalogenase from Pseudomonas sp. strain 113 gene cloning and structural comparison with D- and L-2-haloacid dehalogenases. J Bacterial 179 4232-4238. 

Haloacid dehalogenase-type hydrolase domain in P-type ATPase (Aravind et at, 1998a)... 

Aravind, L., Galperin, M. Y., and Koonin, E. V. (1998a). The catalytic domain of the P-type ATPase has the haloacid dehalogenase fold. Trends Biochem. Sd. 23, 127—129. 

Hisano, T., Hata, Y., Fujii, T., Liu, J. Q., Kurihara, T., Esaki, N., and Soda, K. (1996). Crystal structure of L-2-haloacid dehalogenase from Pseudomonas sp. YL. An alpha/ beta hydrolase structure that is different from the alpha/beta hydrolase fold./ Biol. Chem. 271, 20322-20330. 

HO in above structures is replaced by Enzyme — C in haloacid dehalogenases %... 

In one of the haloacid dehalogenases, a 232-residue protein for which the three-dimensional structure is known,8 9 Asp 10 is in a position to carry out the initial attack which would give an enzyme-bound intermediate with an ester linkage ... 

Haloacid dehalogenase(s) 590 mechanism of 590 Haloalkane dehalogenase(s) 591 active site structure 591 Halocyanin 883 Haloperoxidases 855, 889 Hammerhead ribozyme 649, 651s mechanism of action 651 Hammett equation 308... 

Kurihara T, Esaki N, Soda K (2000) Bacterial 2-Haloacid Dehalogenases Structures and Reaction Mechanisms. J Mol Catal B Enzym 10 57... 

Although a full exposition of these additional superfamilies is beyond the scope of this discussion, a short description of two, the vicinal oxygen chelate fold (VOC) superfamily and the haloacid dehalogenase (HAD) superfamily, are included. Neither of these superfamilies belongs to the a/(3 barrel fold class and a discussion of the way in which each delivers function provides an important contrast to our discussion of the enolase superfamily. 

Comparison of available three-dimensional structures for two haloacid dehalogenases (Hisano et al., 1996 Ridder et al., 1997) with that of a recently solved structure for a phosphonatase (M. Morais and K. N. Allen, unpublished) shows them to be superimposable, with substantial active site similarities associated with an aspartic acid that is rigorously conserved in all the member sequences. As reviewed by Baker et al. (Baker et al., 1998), mechanistic studies of several of the superfamily... 

Comparative modeUing of hmnan PHOSPHOl reveals a new group of phosphatases within the haloacid dehalogenase superfamily. Protein Eng 16 889-895... 

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