METHOD FOR IDENTIFYING MICROORGANISMS VIA MASS SPECTROMETRY AND SCORE NORMALIZATION

摘要

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;f(m)=pN(mμ,σ)pN(mμ,σ)+(1-p)N(mμ_,σ_);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| μ, σ) 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.

主权项

1. A method of identifying by mass spectrometry a microorganism from among a predetermined set of reference microorganisms, each reference microorganism being represented by a set of reference data, the method comprising:
determining a set of data representative of the microorganism to be identified according to a mass spectrometry measurement of said microorganism; and for each reference microorganism, calculating a distance between said determined set of data and the set of reference data of the reference microorganism, wherein the method comprises calculating a probability for the microorganism to be identified to be the reference microorganism, according to relation:f(m)=pN(mμ,σ)pN(mμ,σ)+(1-p)×N(mμ_,σ_)where:
m is the distance calculated for the reference microorganism; f(m) is the probability calculated for said distance m; N(m|μ,σ) is a value, for distance m, of a random variable modeling the distance between a set of data associated with a microorganism to be identified and the set of reference data of the reference microorganism, when the microorganism to be identified is the reference microorganism; N(m| μ, σ) is a value, for distance m, of a random variable modeling the distance between a set of data associated with a microorganism to be identified and the set of reference data of the reference microorganism, when the microorganism to be identified is not the reference microorganism; and p is a predetermined scalar in the range from 0 to 1.