
Full text loading...
Category: Clinical Microbiology; Environmental Microbiology
Antimicrobial Resistance in Listeria Species, Page 1 of 2
< Previous page | Next page > /docserver/preview/fulltext/10.1128/9781555819804/9781555819798_Chap11-1.gif /docserver/preview/fulltext/10.1128/9781555819804/9781555819798_Chap11-2.gifAbstract:
Currently, multidrug resistance is not a common feature encountered in Listeria species. However, as has been observed with other pathogens of importance to humans, Listeria species have the ability to rapidly develop resistance to any antimicrobial agent, a feature that represents an emerging and increasing threat to human and animal health. Isolates of Listeria have been reported with varying degrees of resistance to commonly used antibiotics, and the first multidrug-resistant Listeria isolate was identified in France in 1988. These isolates developed resistance through a number of well-known mechanisms, including target gene mutations, such as within genes encoding efflux pumps, together with the acquisition of mobile genetic elements. This article will focus, in particular, on describing the mechanisms that confer resistance in Listeria species to antibiotics, biocides, and heavy metals.
Full text loading...
Listeria species maximum likelihood phylogenetic tree based on concatenated nucleotide sequences of the 16S rRNA genes from all Listeria species. Values on branches represent bootstrap values based on 500 bootstrap replicates; bootstrap values >80% are not displayed. Listeria species are color coded according the new genera classification proposed by Orsi et al. ( 1 ).
Transmission dynamics of listeriosis involving human and animal hosts. Potential transmission pathways of Listeria species are indicated by arrows, and vehicles are represented by colored boxes.
L. monocytogenes intracellular life cycle. (a) Listeria invades the host cells via a zipper mechanism, by the interaction of surface internalins InlA and InlB with the host cell surface receptors E-cadherin and Met, respectively. (b) Listeria escapes from the phagosome before the fusion with the lysosome occurs, by the action of the secreted proteins, the pore-forming toxin LLO, and phosphatidylinositide phospholipase C (PI-PLC). (c) Listeria may replicate in the cytosol, and (d) it spreads by actin polymerization, which propels the bacteria unidirectionally, (e) promoting cell-to-cell spreading of Listeria. (f) Rupture of the two-membrane vacuole is mainly mediated by the action of LLO and phosphatidylcholine-specific phospholipase C (PC-PLC).
Heavy metal resistance operons in the L. monocytogenes strain ScottA. (A) Arsenic resistance operon. (B) cadAC cadmium resistance operon.
Diagrammatic representation of the four families of efflux pumps in L. monocytogenes. The ATP-binding cassette (ABC) superfamily, the major facilitator superfamily (MFS), the multidrug and toxic-compound extrusion (MATE) family, and the small multidrug resistance (SMR) family. Common examples of the individual proteins that form each class of efflux pump are shown.
Listeria monocytogenes lineages and serotype distribution
Mammals, birds, and other species from which Listeria species have been isolated
Listeria species, hosts, and forms of disease
Intrinsic or natural antibiotic susceptibility and resistance of Listeria species
Multidrug efflux transporters characterzsed in L. monocytogenes