Thursday, March 7, 2013

Applications Thursday: Fluorescence Polarization based High Throughput Screening for inhibitors of bacterial Lipopolysaccharide production

Bordetella_bronchiseptica.jpg
With the increasing concern over antibiotic resistant bacteria it becomes more important to identify other mechanisms that can assist in halting bacterial growth. A potential untapped target are the enzymes that produce components of the lipopolysaccharide (LPS) outer membrane of Gram-negative bacteria. A paper in the recent issue of the Journal of Biomolecular Screening has used a PHERAstar plate reader from BMG LABTECH to perform a novel HTS using a FP based assay  in an attempt to identify inhibitors of LpxA. This enzyme is involved in  the synthesis of the Lipid A component of LPS.

The paper entitled: 'A High-Throughput-Compatible Fluorescence Anisotropy-Based Assay for Competitive Inhibitors of Escherichia coli UDP-N-Acetylglucosamine Acytransferase (LpxA)' is the work of scientists from AstraZeneca in Boston, MA. Their approach reveals inhibitors of LpxA that are able to displace a fluorescent ligand from the active site of LpxA resulting in a decrease in FP signal.

Diagram of PHERAstar FP optic module
Key to the success of this application is the optic modules employed by the PHERAstar which allow for this application to employ low volumes and lowest possible LpxA concentration and still attain satisfactory performance.