Streltsov_2003_Biochemistry_42_10104

Reference

Title : Haloalkane dehalogenase LinB from Sphingomonas paucimobilis UT26: X-ray crystallographic studies of dehalogenation of brominated substrates - Streltsov_2003_Biochemistry_42_10104
Author(s) : Streltsov VA , Prokop Z , Damborsky J , Nagata Y , Oakley A , Wilce MC
Ref : Biochemistry , 42 :10104 , 2003
Abstract :

The haloalkane dehalogenases are detoxifying enzymes that convert a broad range of halogenated substrates to the corresponding alcohols. Complete crystal structures of haloalkane dehalogenase from Sphingomonas paucimobilis UT26 (LinB), and complexes of LinB with 1,2-propanediol/1-bromopropane-2-ol and 2-bromo-2-propene-1-ol, products of debromination of 1,2-dibromopropane and 2,3-dibromopropene, respectively, were determined from 1.8 A resolution X-ray diffraction data. Published structures of native LinB and its complex with 1,3-propanediol [Marek et al. (2000) Biochemistry 39, 14082-14086] were reexamined. The full and partial debromination of 1,2-dibromopropane and 2,3-dibromopropene, respectively, conformed to the observed general trend that the sp(3)-hybridized carbon is the predominant electrophilic site for the S(N)2 bimolecular nucleophilic substitution in dehalogenation reaction. The 2-bromo-2-propene-1-ol product of 2,3-dibromopropene dehalogenation in crystal was positively identified by the gas chromatography-mass spectroscopy (GC-MS) technique. The 1,2-propanediol and 1-bromopropane-2-ol products of 1,2-dibromopropane dehalogenation in crystal were also supported by the GC-MS identification. Comparison of native LinB with its complexes showed high flexibility of residues 136-157, in particular, Asp146 and Glu147, from the cap domain helices alpha(4) and alpha(5)('). Those residues were shifted mainly in direction toward the ligand molecules in the complex structures. It seems the cap domain moves nearer to the core squeezing substrate into the active center closer to the catalytic triad. This also leads to slight contraction of the whole complex structures. The flexibility detected by crystallographic analysis is in remarkable agreement with flexibility observed by molecular dynamic simulations.

PubMedSearch : Streltsov_2003_Biochemistry_42_10104
PubMedID: 12939138
Gene_locus related to this paper: sphpi-linb

Related information

Substrate 2,3-dibromopropene    1,2-dibromopropane
Gene_locus sphpi-linb
Family Haloalkane_dehalogenase-HLD2
Structure 1IZ7    1IZ8    1K5P    1K6E    1K63

Citations formats

Streltsov VA, Prokop Z, Damborsky J, Nagata Y, Oakley A, Wilce MC (2003)
Haloalkane dehalogenase LinB from Sphingomonas paucimobilis UT26: X-ray crystallographic studies of dehalogenation of brominated substrates
Biochemistry 42 :10104

Streltsov VA, Prokop Z, Damborsky J, Nagata Y, Oakley A, Wilce MC (2003)
Biochemistry 42 :10104