Cloning of a gene encoding a major secreted polypeptide of Listeria monocytogenes and its potential use as a species-specific probe

Abstract

A gene, designated msp, that encodes a major secreted polypeptide with a molecular mass of approximately 60 kilodaltons (kDa) was cloned from Listeria monocytogenes 10403. DNA hybridization analysis indicated that the msp gene was highly conserved among 15 independent L. monocytogenes isolates and that each of 5 isolates tested secreted a 60-kDa polypeptide that was immunologically related to the msp gene product. DNA sequences related to msp were not detected in any other Listeria species or in strains of Bacillus cereus, Bacillus thuringiensis, Streptococcus pyogenes, or Streptococcus pneumoniae when standard stringent DNA hybridization conditions were used. Under nonstringent conditions, related sequences were detected in Listeria ivanovii, Listeria seeligeri, and Listeria innocua, and immunoblot analysis indicated that these strains secreted polypeptides of about 60 kDa that were immunologically related to the msp gene product. The possibility of using the msp gene as a probe for the detection of L. monocytogenes and the potential functions of the msp gene product are discussed.

Comparison of methods for discrimination between strains of Listeria monocytogenes from epidemiological surveys

“…DNA fingerprints can be further utilized by Southern blotting and hybridization with Listeria-specific probes. Gene probes have been constructed to detect various virulence factors, including hemolysins (5,40) and delayed hypersensitivity factors (23) in addition to other major secreted proteins (8,17). Many of these factors are present as single-copy genes in Listeria species, making it difficult to detect small numbers of organisms.…”

Detection of Listeria monocytogenes by direct colony hybridization on hydrophobic grid-membrane filters by using a chromogen-labeled DNA probe

“…Several radiolabeled DNA probes for the detection of Listeria spp., or for L. monocytogenes specifically, have been reported (2,4,5,10,14,15,17). Three of the L. monocytogenes-specific probes have been used only for Southern blotting and their use has not yet been extended to colony hybridization (2, 10, 15).…”

Epidemiology of human listeriosis.

“…DNA probes derived from the listeriolysin 0 gene sequence (24, 115), the gene coding for a putative invasion factor of L. monocytogenes (28,29,40,80), and the gene for a delayed-type hypersensitivity factor (125) of L. monocytogenes have been used for the rapid confirmation of L. monocytogenes colonies isolated from food. Mengaud et al (115) and Chenevert et al 24found a 651-bp internal fragment of the listeriolysin gene to be specific for L. monocytogenes under stringent hybridization conditions.…”