PDBsum entry: 1h46

Hydrolase

PDB id: 1h46

Contents

Protein chain

431 a.a. *

Ligands

NAG

RNP

Waters ×325

* Residue conservation analysis

PDB id:

1h46

Name:

Hydrolase

Title:

The catalytic module of cel7d from phanerochaete chrysosporium as a chiral selector: structural studies of its complex with the b-blocker (r)-propranolol

Structure:

Exoglucanase i. Chain: x. Fragment: catalytic module, residues 19-449. Synonym: 1,4-beta-cellobiohydrolase, cellulase, exocellobiohydrolase i, cbh58, cbh1, cbh i, cbh1.2 exocellulase. Other_details: beta-blocker (r)-propranolol

Source:

Phanerochaete chrysosporium. Organism_taxid: 5306. Strain: k3. Atcc: 32629. Other_details: extracellular protein obtained from the fungus phanerochaete chrysosporium

Resolution:

1.52Å R-factor: 0.171 R-free: 0.219

Authors:

I.G.Munoz,S.L.Mowbray,J.Stahlberg

Key ref:

I.G.Muñoz et al. (2003). The catalytic module of Cel7D from Phanerochaete chrysosporium as a chiral selector: structural studies of its complex with the beta blocker (R)-propranolol. Acta Crystallogr D Biol Crystallogr, 59, 637-643. PubMed id: 12657782 DOI: 10.1107/S0907444903001938

Date:

03-Oct-02 Release date: 03-Apr-03

Protein chain

Q7LHI2  (Q7LHI2_PHACH) -  Cellulase

Seq: 540 a.a.

Struc: 431 a.a.*

* PDB and UniProt seqs differ at 1 residue position (black cross)

Enzyme reactions

• Enzyme class: E.C.3.2.1.91 - Cellulose 1,4-beta-cellobiosidase (non-reducing end).
• Reaction: Hydrolysis of 1,4-beta-D-glucosidic linkages in cellulose and cellotetraose, releasing cellobiose from the non-reducing ends of the chains.

 Gene Ontology (GO) functional annotation 

• Biological process: carbohydrate metabolic process (1 term)
• Biochemical function: hydrolase activity, hydrolyzing O-glycosyl compounds (1 term)

DOI no: 10.1107/S0907444903001938

Acta Crystallogr D Biol Crystallogr 59:637-643 (2003)

PubMed id: 12657782

The catalytic module of Cel7D from Phanerochaete chrysosporium as a chiral selector: structural studies of its complex with the beta blocker (R)-propranolol.

I.G.Muñoz, S.L.Mowbray, J.Ståhlberg.

ABSTRACT

Previous investigations have shown that the major cellobiohydrolase of Phanerochaete chrysosporium, Cel7D (CBH 58), can be used to separate the enantiomers of a number of drugs, including adrenergic beta blockers such as propranolol. The structural basis of this enantioselectivity is explored here. A 1.5 A X-ray structure of the catalytic domain of Cel7D in complex with (R)-propranolol showed the ligand bound at the active site in glucosyl-binding subsites -1/+1. The catalytic residue Glu207 makes a strong charge-charge interaction with the secondary amine of (R)-propranolol; this is supported by a second interaction of the amine with the nearby Asp209. The aromatic naphthyl group stacks onto the indole ring of Trp373 (normally the glucosyl-binding platform of subsite +1). Other factors also contribute to good complementarity between the ligand and the substrate-binding cleft of the enzyme. Comparison with the previous structure of a related cellulase, Cel7A from Trichoderma reesei, in complex with (S)-propranolol strongly suggests that these enzymes will bind the (S)-enantiomer in a very similar manner, distinct from their mode of binding to (R)-propranolol. Tighter binding of both enzymes to the (S)-enantiomer is largely explained by two additional hydrogen-bonding interactions with its hydroxyl group. The distinct preference for the (R)-enantiomer is probably a consequence of structural differences near the naphthyl group of the ligand.

Selected figure(s)

Figure 3.
Figure 3 Similarities and differences in ligand docking. (S)-propranolol as bound to Tr_Cel7A (green C atoms in ligand and protein) is superimposed on the complex of Pc_Cel7D and (R)-propranolol (C atoms are light blue in ligand and gold in protein) and shown in divergent stereo. (a) View from `above' the catalytic cleft showing that the active sites are practically identical around most of the ligand. The residue numbers are for Pc_Cel7D. The isopropyl moieties, pointing downwards in this view, and the secondary amino groups are in similar positions. The rest of the amino-alcohol chains have different conformations and the naphthyl groups are shifted. (b) View from the end of the cleft along the bottom of the binding site towards the catalytic residues. Tr_Cel7A (green labels) has a loop (top left) that extends above the active site and which, together with Tyr371 on the opposing loop, encloses the naphthyl moiety of the ligand. In Pc_Cel7D (brown labels) the corresponding loop is shorter and leaves one face of the upper part of the naphthyl exposed to solvent. In both complexes there is room for water molecules between the ligand and the `bottom' of the binding cleft; some from the Pc_Cel7D-(R)-propranolol complex are shown as red spheres. The protein structures were aligned initially by matching residues 207-212 of Pc_Cel7D to 212-217 of Tr_Cel7A; the alignment was improved using a 1.0 Å cutoff. This approach results in an r.m.s. difference of 0.5 Å for 329 C^ atoms.

The above figure is reprinted by permission from the IUCr: Acta Crystallogr D Biol Crystallogr (2003, 59, 637-643) copyright 2003.

Figure was selected by the author.