Type

Journal Article

Authors

Richard O'Kennedy
Paul Leonard
Stephen Hearty
Elizabeth Tully

Subjects

Microbiology

Topics
escherichia coli chemistry quantum dots immunology antibodies monoclonal genetics listeria monocytogenes antibodies bacterial isolation purification immunoassay inlb protein listeria monocytogenes internalin protein bacteria membrane proteins bacterial proteins recombinant proteins

The development of rapid fluorescence-based immunoassays, using quantum dot-labelled antibodies for the detection of Listeria monocytogenes cell surface proteins. (2005)

Abstract Listeria monocytogenes is an important food-borne pathogen with an extremely high mortality rate (approximately 30%). Therefore, a highly sensitive, reproducible and rapid assay for its detection is vital. L. monocytogenes cells employ two surface bound proteins, Internalin A (InlA) and Internalin B (InlB) to promote invasion into host cells. Recombinant forms of both proteins were previously cloned and expressed in Escherichia coli. In this paper we describe how the InlB protein was sub-divided into three shorter overlapping peptide fragments yielding truncated functional protein of M(R) 23, 35 and 45 kDa, respectively. Purification of the InlB fragments by immobilised metal affinity chromatography (IMAC) was optimised and confirmed by electrophoresis and Western blotting. Identification of the antibody binding regions was achieved by probing the expressed polypeptide domains with a panel of antibodies and antibody fragments. The cloned peptide fragments were also used to develop novel fluorescence-based immunoassays incorporating quantum dots. The application of quantum dot-labelled anti-InlA monoclonal antibodies for immunostaining L. monocytogenes was also demonstrated.
Collections Ireland -> Dublin City University -> PubMed

Full list of authors on original publication

Richard O'Kennedy, Paul Leonard, Stephen Hearty, Elizabeth Tully

Experts in our system

1
R O'Kennedy
Dublin City University
Total Publications: 197
 
2
Paul Leonard
Dublin City University
Total Publications: 27
 
3
Stephen Hearty
Dublin City University
Total Publications: 27