Seminars Archive
Jaromir Marek
Abstract
Thursday, July 20, 2000, 11:00
Seminar Room, ground floor, Building "T"
Sincrotrone Trieste, Basovizza
I.D. required for external visitors
Crystal structure of the haloalkane dehalogenase from Sphingomonas paucimobilis
UT26
Jaromir Marek
(MU Brno, Laboratory of Biomolecular Structure and Dynamics)
ABSTRACT
The haloalkane dehalogenase from Sphingomonas paucimobilis UT26 (LinB)
is the enzyme involved in the degradation of important environmental pollutant
g-hexachlorocyclo-he-xane. The enzyme is a/b hydrolase and it hydrolyses
broad range of halogenated cyclic and aliphatic com-pounds.
The methods involved during solution of the 1.58 C crystal structure
of LinB and 2.0 C structure of LinB with 1,3-propanediol, a product of
debromination of 1,3-dibromopropane, in the active site of the enzyme,
will be described here. The refined LinB structures will be compared with
the structures of haloalkane dehalogenase from Xanthobacter autotrophicus
GJ10 and from Rhodococcus sp. We found that arrangement and composition
of the a-helices in the cap domain resulting in the differences in the
size and shape of the active site cavity and the entrance tunnel are the
major determinants of the substrate specificity of the haloalkane dehalogenases.