Shimadzu Corporation

Meijo University

Keio University

Shinji Funatsu

Keisuke Shima

Naomi Yamamoto

Hiroto Tamura

Teruyo Kato

Koretsugu Ogata

Noriyuki Ojima

Yosihiro Yamada

Shuuichi Nakaya

Miyuki Morozumi

Megumi Sakuma

Provided is a method of identifying a serovar ofbacteria including a step of subjecting a sample containing microorganisms to mass spectrometry to obtain a mass spectrum, a step of reading a mass-to-charge ratio m/z of a peak derived from a marker protein from the mass spectrum, and an identification step of identifying a serovar ofbacteria in the sample, based on the mass-to-charge ratio m/z, wherein the serovars ofbacteria are classified using cluster analysis using as an index the mass-to-charge ratio m/z derived from at least 12 types of ribosomal proteins S8, L15, L17, L21, L25, S7, SODa, peptidylprolyl isomerase, gns, YibT, YaiA and YciF as the marker proteins.

Microorganism identification method

An analysis method includes: acquiring data corresponding to a mass spectrum obtained by subjecting a sample containing a microorganism to mass spectrometry; and acquiring information on Group Aof emm type 1, based on the presence or absence, or magnitude of a peak in a first range of m/z of 10930 or more to 10945 or less in the mass spectrum.

Analysis method, analytical method and microorganism identification method

To provide a method for discriminating a microorganism by selecting and using a marker protein capable of reproducibly and quickly discriminating a bacterial species of the genus. The method for discriminating a microorganism according to the present invention includes: a step of subjecting a sample containing a microorganism to mass spectrometry to obtain a mass spectrum; a reading step of reading a mass-to-charge ratio m/z of a peak derived from a marker protein from the mass spectrum; and a discrimination step of discriminating which bacterial species ofbacteria the microorganism contained in the sample contains based on the mass-to-charge ratio m/z, in which at least one of 17 ribosomal proteins L3, L4, L23, L2, L24, L6, L18, S5, L15, S13, S11, L10, L21, L13, S9, L31, S16 is used as the marker protein and particularly at least one of 8 ribosomal proteins L24, L6, L18, L15, S9, L31, S16 among the 17 ribosomal proteins is used.

Method for discriminating a microorganism

A microorganism identification method according to the present invention includes a step of subjecting a sample containing microorganisms to mass spectrometry to obtain a mass spectrum, a step of reading a mass-to-charge ratio m/z of a peak derived from a marker protein from the mass spectrum, and an identification step of identifying which bacteria of serovar ofgenus bacteria the microorganisms contained in the sample contain, based on the mass-to-charge ratio m/z, in which at least one of two types of ribosomal proteins S8 and Peptidylpropyl isomerase is used as the marker protein.

When a user inputs samples per group, a sample tree and a peak matrix are generated. Peak lists per group are shown in the sample tree, and m/z values and signal strength values from the peak lists are coordinates in the peak matrix. A multivariate analysis is applied to the generated peak matrix. The sample tree, peak matrix, score plot, and loading plot are displayed. When the user clicks a plotted point on the loading plot, a row indicating a corresponding peak on the peak matrix is discriminated. When the user deletes a checkmark corresponding to the discriminated row, the multivariate analysis is applied to the peak matrix from which the peak has been excluded. The score plot and other data are updated. When separation between groups is known from the score plot as failure, the excluded peak may be visually determined as a marker contributing to the group separation.

Mass spectrometric data analyzer and mass spectrometric data analyzing program

To provide a method for discriminating a microorganism including: a step of subjecting a sample containing a microorganism to mass spectrometry to obtain a mass spectrum; a reading step of reading a mass-to-charge ratio m/z of a peak derived from a marker protein from the mass spectrum; and a discrimination step of discriminating which bacterial species ofbacteria, andthe microorganism contained in the sample contains based on the mass-to-charge ratio m/z, in which at least one of 13 ribosomal proteins S5, L15, S13, L31, L22, L19, L20, L13, S15, L25, HNS, HdeB, and L29 is used as the marker protein.

Method for discriminating microorganism

A microorganism identification method includes steps of: obtaining a mass spectrum through mass spectrometry of a sample including microorganisms; reading, from the mass spectrum, a mass-to-charge ratio m/z of a peak associated with a marker protein; and identifying which bacterial species of the genusare included in the microorganisms in the sample based on the mass-to-charge ratio m/z. The microorganism identification method is further characterized in that at least one of the following 18 marker proteins is used as the marker protein, S10, L23, S19, L22, L16, L29, S17, L14, L24, S14, L18, L15, L36, S13, S11 (Me), L32, and L7/L12.

A method and apparatus for entering the structures of assumed sugar chains, assumed ionic numbers, m/z of a common product ion, etc. for calculating, by a precursor m/z calculator the m/z of precursor ions originating from each sugar chain. A method file creator prepares a method file including MRM transitions. A multivalent ion information file creator creates a file which associates a unique ID of each sugar-chain structure with m/z of precursor ions and m/z of a product ion. Then, a chromatogram creator creates a mass chromatogram for each MRM transition. A peak area totalizer adds up peak areas on mass chromatograms obtained for a plurality of MRM transitions corresponding to the same sugar chain. Based on the calculated total values, a quantitative value calculator calculates an abundance ratio of each sugar chain as a quantitative value. A quantitative output information creator displays the quantitative values on a display unit.

Method for quantitative analysis of high-molecular compound and data-processing device for the quantitative analysis

Mass analysis is performed on the same sample while changing the cooling gas supply rate to the ion trap, i.e. the gas pressure conditions, and the respective mass spectra are obtained. Under high gas, ion energy will decrease and modifiers such as phosphate groups will not detach readily, while under low gas, ion energy will remain high and so detachment of modifiers will occur readily. Thus, between multiple mass spectra obtained while changing the gas pressure, if the mass difference between a peak for which signal intensity increased and a peak for which it decreased corresponds to the mass of a known modifier or an integer multiple thereof, it can be inferred that those peaks have the same basic structure and differ only in the number of modifiers. Thus, such peaks are selected as precursor ions to perform MSanalysis and structural analysis.

Growing community of inventors

Kyoto, Japan

Shinji Funatsu