PDBsum entry 1o2e

Hydrolase

PDB id: 1o2e

Contents

Protein chain

123 a.a. *

Ligands

ANN

Metals

_CA

Waters ×43

* Residue conservation analysis

PDB id:

1o2e

Name:

Hydrolase

Title:

Structure of the triple mutant (k53,56,120m) + anisic acid complex of phospholipase a2

Structure:

Phospholipase a2. Chain: a. Synonym: phosphatidylcholine 2- acylhydrolase, group ib phospholipase a2. Engineered: yes. Mutation: yes

Source:

Bos taurus. Cattle. Organism_taxid: 9913. Expressed in: escherichia coli. Expression_system_taxid: 562.

Resolution:

2.60Å R-factor: 0.187 R-free: 0.241

Authors:

K.Sekar,D.Velmurugan,M.D.Tsai

Key ref:

K.Sekar et al. (2003). Crystal structures of the free and anisic acid bound triple mutant of phospholipase A2. J Mol Biol, 333, 367-376. PubMed id: 14529623 DOI: 10.1016/j.jmb.2003.08.032

Date:

05-Mar-03 Release date: 09-Sep-03

Protein chain

P00593  (PA21B_BOVIN) -  Phospholipase A2 from Bos taurus

Seq: 145 a.a.

Struc: 123 a.a.*

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

Enzyme reactions

• Enzyme class: E.C.3.1.1.4 - phospholipase A2.
• Reaction: a 1,2-diacyl-sn-glycero-3-phosphocholine + H2O = a 1-acyl-sn-glycero-3- phosphocholine + a fatty acid + H⁺
• Cofactor: Ca(2+)

Molecule diagrams generated from .mol files obtained from the KEGG ftp site

reference

DOI no: 10.1016/j.jmb.2003.08.032

J Mol Biol 333:367-376 (2003)

PubMed id: 14529623

Crystal structures of the free and anisic acid bound triple mutant of phospholipase A2.

K.Sekar, S.Vaijayanthi Mala, M.Yogavel, D.Velmurugan, M.J.Poi, B.S.Vishwanath, T.V.Gowda, A.A.Jeyaprakash, M.D.Tsai.

ABSTRACT

Phospholipase A2 catalyses the hydrolysis of the ester bond of 3-sn-phosphoglycerides. Here, we report the crystal structures of the free and anisic acid-bound triple mutant (K53,56,120M) of bovine pancreatic phospholipase A2. In the bound triple mutant structure, the small organic molecule p-anisic acid is found in the active site, and one of the carboxylate oxygen atoms is coordinated to the functionally important primary calcium ion. The other carboxylate oxygen atom is hydrogen bonded to the phenolic hydroxyl group of Tyr69. In addition, the bound anisic acid molecule replaces one of the functionally important water molecules in the active site. The residues 60-70, which are in a loop (surface loop), are disordered in most of the bovine pancreatic phospholipase A2 structures. It is interesting to note that these residues are ordered in the bound triple mutant structure but are disordered in the free triple mutant structure. The organic crystallization ingredient 2-methyl-2,4-pentanediol is found near the active site of the free triple mutant structure. The overall tertiary folding and stereochemical parameters for the final models of the free and anisic acid-bound triple mutant are virtually identical.

Selected figure(s)

Figure 1.
Figure 1. The backbone tracing of the free triple mutant. The surface loop residues (60-70) and the calcium-binding loop (27-34) are indicated with the residue numbers at the beginning as well as at the ends. This Figure was produced using the program MOLSCRIPT.[44.]

Figure 4.
Figure 4. Stereo view of the omit electron density map contoured at the 1.0s level showing the electron density for the anisic acid molecule in the bound triple mutant structure. In addition, the only water molecule hydrogen bonded to Nd1 of His48 is shown and it is 0.49 Å below the plane of the histidine ring.

The above figures are reprinted by permission from Elsevier: J Mol Biol (2003, 333, 367-376) copyright 2003.

Figures were selected by an automated process.