Uppenberg J

References (3)

Title : Crystallographic and molecular-modeling studies of lipase B from Candida antarctica reveal a stereospecificity pocket for secondary alcohols - Uppenberg_1995_Biochemistry_34_16838
Author(s) : Uppenberg J , Ohrner N , Norin M , Hult K , Kleywegt GJ , Patkar S , Waagen V , Anthonsen T , Jones TA
Ref : Biochemistry , 34 :16838 , 1995
Abstract : Many lipases are potent catalysts of stereoselective reactions and are therefore of interest for use in chemical synthesis. The crystal structures of lipases show a large variation in the shapes of their active site environments that may explain the large variation in substrate specificity of these enzymes. We have determined the three-dimensional structure of Candida antarctica lipase B (CALB) cocrystallized with the detergent Tween 80. In another crystal form, the structure of the enzyme in complex with a covalently bound phosphonate inhibitor has been determined. In both structures, the active site is exposed to the external solvent. The potential lid-forming helix alpha 5 in CALB is well-ordered in the Tween 80 structure and disordered in the inhibitor complex. The tetrahedral intermediates of two chiral substrates have been modeled on the basis of available structural and biochemical information. The results of this study provide a structural explanation for the high stereoselectivity of CALB toward many secondary alcohols.
ESTHER : Uppenberg_1995_Biochemistry_34_16838
PubMedSearch : Uppenberg_1995_Biochemistry_34_16838
PubMedID: 8527460
Gene_locus related to this paper: canar-LipB

Title : Crystallization and preliminary X-ray studies of lipase B from Candida antarctica - Uppenberg_1994_J.Mol.Biol_235_790
Author(s) : Uppenberg J , Patkar S , Bergfors T , Jones TA
Ref : Journal of Molecular Biology , 235 :790 , 1994
Abstract : Lipase B from Candida antarctica has been crystallized in five different crystal forms. The space groups and cell dimensions have been determined by X-ray diffraction methods. Four of the crystal forms have been judged to be of good quality for further X-ray studies. The best crystals diffract to 1.7 Angstrom.
ESTHER : Uppenberg_1994_J.Mol.Biol_235_790
PubMedSearch : Uppenberg_1994_J.Mol.Biol_235_790
PubMedID: 8289302
Gene_locus related to this paper: canar-LipB

Title : The sequence, crystal structure determination and refinement of two crystal forms of lipase B from Candida antarctica - Uppenberg_1994_Structure_2_293
Author(s) : Uppenberg J , Hansen MT , Patkar S , Jones TA
Ref : Structure , 2 :293 , 1994
Abstract : BACKGROUND: Lipases constitute a family of enzymes that hydrolyze triglycerides. They occur in many organisms and display a wide variety of substrate specificities. In recent years, much progress has been made towards explaining the mechanism of these enzymes and their ability to hydrolyze their substrates at an oil-water interface.
RESULTS: We have determined the DNA and amino acid sequences for lipase B from the yeast Candida antarctica. The primary sequence has no significant homology to any other known lipase and deviates from the consensus sequence around the active site serine that is found in other lipases. We have determined the crystal structure of this enzyme using multiple isomorphous replacement methods for two crystal forms. Models for the orthorhombic and monoclinic crystal forms of the enzyme have been refined to 1.55 A and 2.1 A resolution, respectively. Lipase B is an alpha/beta type protein that has many features in common with previously determined lipase structures and other related enzymes. In the monoclinic crystal form, lipid-like molecules, most likely beta-octyl glucoside, can be seen close to the active site. The behaviour of these lipid molecules in the crystal structure has been studied at different pH values. CONCLUSION: The structure of Candida antarctica lipase B shows that the enzyme has a Ser-His-Asp catalytic triad in its active site. The structure appears to be in an 'open' conformation with a rather restricted entrance to the active site. We believe that this accounts for the substrate specificity and high degree of stereospecificity of this lipase.
ESTHER : Uppenberg_1994_Structure_2_293
PubMedSearch : Uppenberg_1994_Structure_2_293
PubMedID: 8087556
Gene_locus related to this paper: canar-LipB