| DATABASE FILE: |
MEDLINE SUBSET [Toxicity & Carcinogenicity
Bibliographic References] |
| CAS REGISTRY NUMBER: |
156319-92-5 |
| CHEMICAL NAME: |
Bacterial Outer Membrane Proteins;
Organophosphorus Compounds; Opa protein, Neisseria meningitidis |
| TITLE: |
Cloning and expression of a gene encoding a
bacterial enzyme for decontamination of organophosphorus nerve agents and nucleotide
sequence of the enzyme. |
| AUTHOR: |
Cheng TC; Harvey SP;
Chen GL |
| ADDRESS: |
U.S. Army Edgewood Research, Development and
Engineering Center, Research and Technology Directorate, Aberdeen Proving Ground, Maryland
21010, USA. tccheng@cbdcom.apgea.army.mil |
| SOURCE/JOURNAL: |
Appl Environ Microbiol; 62(5), p.
1636-41; 1996; ISSN: 0099-2240 |
| PUBLICATION YEAR: |
1996 |
| LANGUAGE: |
English |
| INDEX TERMS: |
|
Organophosphorus Compounds
[Metabolism]; Amino Acid Sequence; Escherichia coli
[Genetics]; Molecular Sequence Data; Sequence
Alignment; Sequence Analysis; Bacterial Outer Membrane Proteins
[Genetics]; Bacterial Outer Membrane Proteins [Metabolism] |
| ABSTRACT: |
|
Organophosphorus acid (OPA)
anhydrolase enzymes have been found in a wide variety of prokaryotic and eukaryotic
organisms. Interest in these enzymes has been prompted by their ability to catalyze the
hydrolysis of toxic organophosphorus cholinesterase-inhibiting compounds, including
pesticides and chemical nerve agents. The natural substrates for these enzymes are
unknown. The gene (opaA) which encodes an OPA anhydrolase (OPAA-2) was isolated from an
Alteromonas sp. strain JD6.5 EcoRI-lambda ZAPII chromosomal library expressed in
Escherichia coli and identified by immunodetection with anti-OPAA-2 serum. OPA anhydrolase
activity expressed by the immunopositive recombinant clones was demonstrated by using
diisopropylfluorophosphate (DFP) as a substrate. A comparison of the recombinant enzyme
with native, purified OPAA-2 showed they had the same apparent molecular mass (60 kDa),
antigenic properties, and enzyme activity against DFP and the chemical nerve agents sarin,
soman, and O-cyclohexyl methylphosphonofluoridate. The gene expressing this activity was
found in a 1.74-kb PstI-HindIII fragment of the original 6.1-kb EcoRI DNA insert. The
nucleotide sequence of this PstI-HindIII fragment revealed an open reading frame of 1,551
nucleotides, coding for a protein of 517 amino acid residues. Amino acid sequence
comparison of OPAA-2 with the protein database showed that OPAA-2 is similar to a
647-amino-acid sequence produced by an open reading frame which appears to be the E. coli
pepQ gene. Further comparison of OPAA-2, the E. coli PepQ protein sequence, E. coli
aminopeptidase P, and human prolidase showed regions of different degrees of similarity or
functionally conserved amino acid substitutions. These findings, along with preliminary
data confirming the presence of prolidase activity expressed by OPAA-2, suggest that the
OPAA-2 enzyme may, in nature, be used in peptide metabolism. |
| PUB. TYPE: |
JOURNAL ARTICLE |
| GENE BANK: |
GENBANK/U29240 |
| STUDY TYPE: |
Human |
| CIS RECORD ID.: |
CM-0004094 |
|
This record is provided from the MEDLINE
database of the National Library of Medicine (NLM), United States. |