CASP2 Target T0006

1. Protein Name

Outer Membrane Phospholipase A

2. Organism Name

Escherichia coli

3. Number of amino acids (approx)

269

4. Accession number

p00631

5. Sequence Database

Swiss-prot

6. Amino acid sequence

SQ SEQUENCE 289 AA; 33171 MW; 9A8C0B91 CRC32;
MRTLQGWLLP VFMFAMAVYA QEATVKEVHD APAVRGSIIA NMLQEHDNPF TLYPYDTNYL
IYTQTSDLNK EAIASYDWAE NARKDEVKFQ LSLAFPLWRG ILGPNSVLGA SYTQKSWWQL
SNSEESSPFR ETNYEPQLFL GFATDYRFAG WTLRDVEMGY NHDSNGRSDP TSRSWNRLYT
RLMAENGNWL VEVKPWYVVG NTDDNPDITK YMGYYQLKIG YHLGDAVLSA KGQYNWNTGY
GGAELGLSYP ITKHVRLYTQ VYSGYGESLI DYNFNQTRVG VGVMLNDLF

7. Homologous Sequence of known structure

no

8. Current state of the experimental work

Outer Membrane Phospholipase A (OMPLA) from E.coli has been cloned and over expressed without it signal sequence,
a purification and refolding protocol yielding active protein has been made [Dekker et al. Eur.J. Biochem. 232:214-219,1995].
A crystal protocol has been reported which resulted in large enough crystals for succesfull structure determination
[Blaauw et al. FEBS letters 373:10-12 1995]. In house crystals diffract to about 3 A resolution.
No homologous structures have been reported yet, no molecular replacement is in progress. At present the search for
heavy atom derivatives is on going. No derivative is yet found. A selenomethionine mutant is under construction. And
a cystein mutant is being crystalised.

9. Interpretable map?

no

10. Estimated date of chain tracing completion

September 1996

11. Estimated date of public release of structure

1997

13. Name

unavailable until after public release of structure

12. Additional Information

Usefull reference with short abstract:
Molecular characterization of enterobacterial pldA genes encoding outer
membrane phospholipase A.
R, G, Brok, E, Brinkman, R, van-Boxtel, A, C, Bekkers, H, M, Verheij, J, Tommassen
J-Bacteriol
1994 Feb
176(3)
861-70
The pldA gene of Escherichia coli encodes an outer membrane
phospholipase A. A strain carrying the most commonly used mutant pldA allele
appeared to express a correctly assembled PldA protein in the outer
membrane. Nucleotide sequence analysis revealed that the only difference
between the wild type and the mutant is the replacement of the serine
residue in position 152 by phenylalanine. Since mutants that lack the pldA
gene were normally viable under laboratory conditions and had no apparent
phenotype except for the lack of outer membrane phospholipase activity, the
exact role of the enzyme remains unknown. Nevertheless, the enzyme seems to
be important for the bacteria, since Western blotting (immunoblotting) and
enzyme assays showed that it is widely spread among species of the family
Enterobacteriaceae. To characterize the PldA protein further, the pldA genes
of Salmonella typhimurium, Klebsiella pneumoniae, and Proteus vulgaris were
cloned and sequenced. The cloned genes were expressed in E. coli, and their
gene products were enzymatically active. Comparison of the predicted PldA
primary structures with that of E. coli PldA revealed a high degree of
homology, with 79% of the amino acid residues being identical in all four
proteins. Implications of the sequence comparison for the structure and the
structure-function relationship of PldA protein are discussed.

Related Files

Template PDB file