Mass spectrometric measurement of microbial resistances

Patent metadata

Field	Value
Publication number	US-9897613-B2
Application number	US-201514697674-A
Country	US
Kind code	B2
Filing date	Apr 28, 2015
Priority date	May 9, 2006
Publication date	Feb 20, 2018
Grant date	Feb 20, 2018

Abstract

Microorganisms, particularly bacteria, are identified and characterized on the basis of a mass spectrometric measurement of their protein profiles with ionization by matrix-assisted laser desorption. In order to measure the microbial resistance to antibiotics, the protein profiles of microorganisms are measured after cultivation for a short time duration in nutrient media containing the antibiotics.

First claim

What is claimed is:

1. A method for determining the resistance of microbes to an antibiotic, comprising:
cultivating a sample of the microbes in a nutrient medium containing the antibiotic;
acquiring a mass spectrum of the cultivated sample;
comparing the mass spectrum to reference mass spectra of resistant and/or non-resistant microbes wherein the reference mass spectra comprise spectra of microbes different than the microbes of the sample and are acquired after the antibiotic has acted on the resistant and/or non-resistant microbes; and
determining the microbes to be resistant if the mass spectrum is similar to a reference mass spectrum of a resistant microbe or to be non-resistant if the mass spectrum is similar to a reference mass spectrum of a non-resistant microbe.

2. The method of claim 1 , wherein the sample of the microbes is cultivated a liquid nutrient medium.

3. The method of claim 2 , wherein the liquid nutrient medium is contained in a microvessel of a microtitration plate.

4. The method of claim 2 , wherein the microbes are removed from the liquid nutrient medium by filtration or centrifuging prior to acquiring the mass spectrum of the removed microbes.

5. The method of claim 4 , wherein the removed microbes are applied to a mass spectrometric support and a matrix solution is sprinkled onto the microbes on the support.

6. The method of claim 4 , wherein the removed microbes are mixed with a matrix solution and wherein the mixture is applied to a mass spectrometric sample support and dried on the mass spectrometric sample support.

7. The method of claim 1 , wherein the sample of the microbes is taken from a homogeneous colony.

Assignees

• Bruker Daltonik Gmbh

Inventors

• Govorun Vadim Markovich
• Franzen Jochen

Classifications

• C12Q1/18

  Testing for antimicrobial activity of a material · CPC title

• G01N33/6851 Primary

  Methods of protein analysis involving laser desorption ionisation mass spectrometry · CPC title

• G01N33/6848

  Methods of protein analysis involving mass spectrometry · CPC title

• C12Q1/04 Primary

  Determining presence or kind of microorganism; Use of selective media for testing antibiotics or bacteriocides; Compositions containing a chemical indicator therefor {(C12Q1/6897 takes precedence)} · CPC title