Description
The VIM/NDM carbapenemase (qPCR) product is used to determine the sequences of genes encoding VIM and NDM carbapenemases in DNA preparations obtained from human material.
Product characteristics
Kit size: 100 markers
Reaction: triplex (FAM: VIM carbapenemases, HEX: internal control, Texas Red: NDM carbapenemases)
Internal control: exogenous/endogenous
Determination: qualitative/quantitative
Kit components:
- Reaction mixture: contains DNA polymerase, probes and primers, and other qPCR reaction components;
- Positive control;
- Negative control;
- PCR-grade water;
- Internal control
Carbapenem resistance
The most common mechanism of resistance of Enterobacterales to carbapenems is the production of carbapenemases, which mainly include KPC, NDM, VIM, IMP, and OXA-48-like. Most of them are encoded on plasmids. Therefore, carbapenem resistance genes spread easily through horizontal gene transfer. Another less common mechanism of carbapenem resistance is the combination of extended-spectrum beta-lactamase (ESBL) or AmpC expression and porin loss or overexpression of efflux pumps.
Carbapenem-resistant Enterobacterales (CRE) resulting from the first mechanism are referred to as carbapenemase-producing CRE (CP-CRE). Carbapenem-resistant Enterobacterales resulting from the second mechanism are referred to as non-carbapenemase-producing CRE (non-CP-CRE).
VIM and NDM carbapenemases
Both types of carbapenemases belong to class B β-lactamases (MBL). The MBL class represents the most distinct evolutionary and structural lineage of these enzymes, and its functional specificity is most notable for its dependence on zinc ions and its natural ability to hydrolyze carbapenems. The substrate spectrum of the vast majority of MBLs is very broad and also includes penicillins and first- to fourth-generation cephalosporins.
The first gene encoding carbapenemase VIM (Verona Integron-Encoded Metallo-beta-lactamase) was identified in late 1997 in P. auregionas in Verona, Italy. Since then, more than 69 variants of this gene have been described. VIM variants occur mainly in Pseudomonas, Acinetobacter, and Enterobacteriaceae species, which are found worldwide. NDM carbapenemase, on the other hand, was first identified in 2008 in a Klebsiella pneumoniae isolate taken from a Swedish patient hospitalized in India.
The first member of the NDM group of carbapenemases was first identified in 2008 in a Klebsiella pneumoniae isolate taken from a Swedish patient hospitalized in India. The name of this group of enzymes derives from the place of its discovery: NDM, New Delhi metallo-β-lactamase.
