PDBsum entry 1be8

Serine protease

PDB id: 1be8

Contents

Protein chain

274 a.a. *

Ligands

TCA

Metals

_CA

Waters ×87

* Residue conservation analysis

PDB id:

1be8

Name:

Serine protease

Title:

Trans-cinnamoyl-subtilisin in water

Structure:

Subtilisin carlsberg. Chain: a. Ec: 3.4.21.62

Source:

Bacillus licheniformis. Organism_taxid: 1402

Resolution:

2.20Å R-factor: 0.180 R-free: 0.223

Authors:

J.L.Schmitke,L.J.Stern,A.M.Klibanov

Key ref:

J.L.Schmitke et al. (1998). Comparison of x-ray crystal structures of an acyl-enzyme intermediate of subtilisin Carlsberg formed in anhydrous acetonitrile and in water. Proc Natl Acad Sci U S A, 95, 12918-12923. PubMed id: 9789015 DOI: 10.1073/pnas.95.22.12918

Date:

20-May-98 Release date: 28-Oct-98

Protein chain

P00780  (SUBC_BACLI) -  Subtilisin Carlsberg from Bacillus licheniformis

Seq: 379 a.a.

Struc: 274 a.a.*

* PDB and UniProt seqs differ at 3 residue positions (black crosses)

Enzyme reactions

• Enzyme class: E.C.3.4.21.62 - subtilisin.
• Reaction: Hydrolysis of proteins with broad specificity for peptide bonds, and a preference for a large uncharged residue in P1. Hydrolyzes peptide amides.

DOI no: 10.1073/pnas.95.22.12918

Proc Natl Acad Sci U S A 95:12918-12923 (1998)

PubMed id: 9789015

Comparison of x-ray crystal structures of an acyl-enzyme intermediate of subtilisin Carlsberg formed in anhydrous acetonitrile and in water.

J.L.Schmitke, L.J.Stern, A.M.Klibanov.

ABSTRACT

The x-ray crystal structures of trans-cinnamoyl-subtilisin, an acyl-enzyme covalent intermediate of the serine protease subtilisin Carlsberg, have been determined to 2.2-A resolution in anhydrous acetonitrile and in water. The cinnamoyl-subtilisin structures are virtually identical in the two solvents. In addition, their enzyme portions are nearly indistinguishable from previously determined structures of the free enzyme in acetonitrile and in water; thus, acylation in either aqueous or nonaqueous solvent causes no appreciable conformational changes. However, the locations of bound solvent molecules in the active site of the acyl- and free enzyme forms in acetonitrile and in water are distinct. Such differences in the active site solvation may contribute to the observed variations in enzymatic activities. On prolonged exposure to organic solvent or removal of interstitial solvent from the crystal lattice, the channels within enzyme crystals are shown to collapse, leading to a drop in the number of active sites accessible to the substrate. The mechanistic and preparative implications of our findings for enzymatic catalysis in organic solvents are discussed.

Selected figure(s)

Figure 1.
Fig. 1. Ribbon diagram of the protein structure of trans-cinnamoyl-subtilisin in acetonitrile. The catalytic triad (Asp-32, His-64, and Ser-221) is portrayed as sticks. The cinnamoyl group is shown in black. Water molecules and acetonitrile molecules are depicted by balls-and-sticks, with the nitrogen atoms of acetonitrile in black.

Figure 2.
Fig. 2. Ribbon diagram of the protein structure of trans-cinnamoyl-subtilisin in water. The catalytic triad and cinnamoyl group (black) are portrayed as sticks. Water molecules are depicted by gray balls.

Figures were selected by an automated process.