Thermo Scientific™ Brilliance™ Listeria Agar Base

Description

• Brilliance Listeria Agar Base is a chromogenic medium for the isolation, enumeration, and presumptive identification of Listeria spp., including Listeria monocytogenes
• Description Listeria monocytogenes is the most common pathogenic Listeria spp
• and has been shown to be pathogenic to both man and animals
• Some Listeria ivanovii strains also possess lecithinase activity and, although Listeria ivanovii are primarily pathogenic to animals, there are strains which have been shown to cause infection in humans
• Brilliance Listeria Agar uses the chromogen X-glucoside for presumptive identification of Listeria spp
• This chromogen is cleaved by β-glucosidase which is common to all Listeria species
• Other organisms that possess this enzyme, such as enterococci , are inhibited by the selective agents within the medium; lithium chloride, polymyxin B and nalidixic acid, while amphotericin inhibits the growth of any yeasts and moulds present in the sample
• Listeria monocytogenes and pathogenic Listeria ivanovii are then further differentiated by their ability to produce the phospholipase enzyme, lecithinase
• This enzyme hydrolyses the lecithin in the medium, producing an opaque white halo around the colony
• Brilliance Listeria Agar is a modification of the formulation described by Ottaviani and Agosti
• As in the original formulation, the medium is designed to identify Listeria spp
• based on their utilization of a chromogenic substrate
• However, in this modification, the pathogenic Listeria spp
• are then further differentiated by the detection of lecithinase (phosphotidylcholine phospholipase C (PCPLC) activity, rather than phosphotidylinositol phospholipase C (PIPLC) activity
• Both enzymes, PCPLC and PIPLC, are associated with virulence in Listeria spp., and, therefore, the presence of either enzyme is a useful indicator of pathogenicity
• Also available Chromogenic Listeria Selective Supplement, Part No
• SR0227E and Chromogenic Listeria Differential Supplement, Part No
• SR0228E
• Appearance Dehydrated medium: Straw coloured, free-flowing powder Prepared medium: Translucent, white gel Quality Control Positive Controls - Expected Results: Listeria monocytogenes ATCC™ 7644™ - Good growth; blue/green colonies with haloes Listeria innocua ATCC™ 33090™ - Good growth; blue/green colonies with no halo Negative Control - Expected Results: Enterococcus feacalis ATCC™ 29212™ - Inhibited The ATCC Licensed Derivative Emblem, the ATCC Licensed Derivative word mark, and the ATCC catalog marks are trademarks of ATCC™ and used under licence.