Method and probe for identifying bacterial virulence modifying agents, agents thus identifed, and their use
AssigneeInnate Pharmaceuticals AB
InventorsAnna Kauppi, Jan Elofsson, Hans Wolf-Watz, Olov Nordfelth, Markus Dahlgren
Life of this patent
Estimating the term…
Abstract
A method for identifying antibacterial agents comprises depleting bacteria of a strain comprising a luxAB construct of Ca2+, incubating the Ca2+ depleted bacteria with an agent the antibacterial effect of which shall be determined, recording the light emitted by the bacteria upon addition of an aldehyde, the incubation being carried out at a temperature which is at least 10° C. higher than the temperature at which the light is emitted by the bacteria. Also disclosed are corresponding probes and antibacterial agents identified by the method.
Claims25
A method for identifying antibacterial agents comprising:
- incubating a Ca2+ depleted bacteria of a strain comprising a luxAB construct with an agent the antibacterial effect of which shall be determined, recording the light emitted by the bacteria upon addition of an aldehyde, the incubation being carried out at a temperature which is at least 10° C. higher than the temperature at which the light is emitted by the bacteria.
A method for identifying antibacterial agents comprising:
- providing a Yersinia sp. bacterial strain comprising a luxAB construct;
- propagating the strain at room temperature in a Ca2+ depleting medium to obtain a suspension of Ca2+ depleted bacteria containing the luxAB construct;
- dissolving a sample of an antibacterial agent candidate in a solvent to prepare a solution of the agent;
- combining the solution of the agent with an aliquot of the bacterial suspension to obtain a test suspension;
- incubating the test suspension at a first temperature for a selected period of time;
- raising the temperature of the test suspension to a second temperature;
- continuing incubation at the second temperature for a period of time;
- lowering the temperature of the test suspension to a third temperature;
- continuing the incubation at the third temperature for a period of time;
- adding n-decanal or a functionally equivalent aldehyde thereto to the test suspension;
- measuring light emitted from the test suspension over a period of time at the third temperature;
- quantifying the light emitted;
- and
- calculating an antibacterial activity based on the quantity of emitted light.
- wherein said first and third temperature is from 20° C. to 26° C. and the second temperature is about 37° C.
6-7. (canceled)
(canceled)
(canceled)
A method of decreasing virulence of Gram-negative bacterial having a type II secretion(TTS) system comprising exposing said bacteria to a structural element X—CO—NH—Y-Z, wherein X is aromatic or heteroaromatic, Y is absent or is —N═CH, and Z is unsubstituted or substituted aryl or heteroaryl.
20-21. (canceled)
A method of screening for agents inhibiting virulence in Gram-negative bacteria having a type III secretion (TTS) system, the method comprising contacting in absence of eukaryotic cells a gram-negative bacterium culture depleted in Ca2+ comprising a luxAB reporter gene construct, with a potentially bacterial virulence inhibiting agent, thereby forming a test suspension, manipulating the temperature of the test suspension and adding an aliphatic aldehyde to make the bacterium emit light, measuring the emitted light, comparing the amount of emitted light with the light emitted in absence of the bacterial virulence inhibiting or activating agent.
24-29. (canceled)
A compound capable of reducing virulence in Gram-negative bacterial having a type III secretion (TTS) system selected from the group consisting of:
Dependencies are inferred from the claim text.