US 12,455,285 B2
Method for detecting bacteria according to the gram signal thereof in a complex sample
Aurore Duquenoy, Lyons (FR); Samuel Bellais, Lyons (FR); and Vincent Thomas, Lyons (FR)
Assigned to MaaT PHARMA, Lyons (FR); and BIOASTER, Lyons (FR)
Appl. No. 17/253,613
Filed by MaaT PHARMA, Lyons (FR); and BIOASTER, Lyons (FR)
PCT Filed Jun. 13, 2019, PCT No. PCT/FR2019/051435
§ 371(c)(1), (2) Date Dec. 17, 2020,
PCT Pub. No. WO2019/243714, PCT Pub. Date Dec. 26, 2019.
Claims priority of application No. 1855350 (FR), filed on Jun. 18, 2018.
Prior Publication US 2021/0172948 A1, Jun. 10, 2021
Int. Cl. G01N 33/569 (2006.01); C12Q 1/04 (2006.01)
CPC G01N 33/56911 (2013.01) [C12Q 1/04 (2013.01); G01N 2333/4724 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A method for detecting, in a sample containing bacteria, the proportion of Gram-positive bacteria relative to the proportion of Gram-negative bacteria, comprising the steps of:
a) incubating the sample, simultaneously or sequentially, with:
wheat lectin (WGA) coupled to a first fluorochrome,
vancomycin coupled to a second fluorochrome emitting a fluorescence at a different wavelength from the first fluorochrome coupled to WGA,
optionally vancomycin that is not coupled to a fluorochrome,
optionally potassium chloride,
b) centrifuging the sample resulting from step a),
c) optionally washing the sample resulting from step b), and
d) measuring the fluorescence of the first and second fluorochromes of the sample resulting from step b) or c) using flow cytometry at different wavelengths to determine the proportion of Gram-positive bacteria relative to the proportion of Gram-negative bacteria in the sample.