Biomerieux, Inc.

Commissariat a L'energie Atomique

Grégory Strubel

Maud Arsac

Pierre-Jean Cotte-Pattat

Denis Desseree

Pierre Mahe

Pierre Grangeat

Jean-Francois Giovannelli

A method of identifying a microorganism by mass spectrometry, including acquiring at least one mass spectrum of said microorganism; for each acquired mass spectrum: detecting peaks of the spectrum in a predetermined mass range; generating a list of peaks identifying at most one peak in each interval of a predetermined subdivision of the range of mass-to-charge ratios, the width of the intervals of the subdivision logarithmically increasing along with the mass-to-charge ratio, and analyzing the list(s) of peaks obtained according to a knowledge base of previously-identified microorganisms and/or types of microorganisms.

Method for identifying microorganisms by mass spectrometry

An identification by mass spectrometry of a microorganism from among reference microorganisms represented by reference data sets includes: determining a set of data of the microorganism according to a spectrum; for each reference microorganism, calculating a distance between the determined and reference sets; and calculating a probability ƒ(m) according to relation where: m is the distance calculated for the reference microorganism; N(m|μ,σ) is the value, for m, of a random variable modeling the distance between a reference microorganism to be identified and the reference microorganism, when the microorganism is the reference microorganism; N(m|,) is the value, for m, of a random variable modeling the distance between a microorganism to be identified and the reference microorganism, when the microorganism is not the reference microorganism; and p is a scalar in the range from 0 to 1.

Method for identifying microorganisms by mass spectrometry and score normalization

An identification by mass spectrometry of a microorganism from among reference microorganisms represented by reference data sets includes: determining a set of data of the microorganism according to a spectrum; for each reference microorganism, calculating a distance between the determined and reference sets; and calculating a probability f(m) according to relation where: m is the distance calculated for the reference microorganism; N(m|&#x3bc;,&#x3c3;) is the value, for m, of a random variable modeling the distance between a reference microorganism to be identified and the reference microorganism, when the microorganism is the reference microorganism; N(m|,) is the value, for m, of a random variable modeling the distance between a microorganism to be identified and the reference microorganism, when the microorganism is not the reference microorganism; and p is a scalar in the range from 0 to 1.

Method for identifying microorganisms via mass spectrometry and score normalization

A method for estimating molecule concentrations in a sample, the method including: obtaining a signal generated by a sample analyzing apparatus, the signal including at least one spectrum, the spectrum including peaks representative of the molecule concentrations in the sample and being expressed as a function of at least one variable; obtaining an analytical modeling of the signal with a modeling function, wherein the modeling function is based on the molecule concentrations and factors including gain factors of the equipment and description factors of the peaks; selecting uncertain factors in the factors; determining a priori probability distributions for the uncertain factors and the molecule concentrations; establishing, with the modeling function and the signal, posteriori probability distributions for the molecule concentrations and the uncertain factors; and estimating, with a processing module, the molecule concentrations and the uncertain factors from a parameter inferred from the posteriori probability distributions.

Growing community of inventors

Manosque, France

Grégory Strubel