This disclosure relates to the field of mass spectrometry analysis. In some embodiments, the disclosure relates to compositions and methods for detecting and quantifying proteins in the AKT-mTOR pathway by immunoprecipitation enrichment followed by mass spectrometry analysis.

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 Listeria. 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 of Listeria bacteria 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.

Disclosed is a method of isolating extracellular vesicles and identifying membrane proteins therefrom. The method includes providing human plasma and/or serum; separating lipoproteins and extracellular vesicles from the human plasma and/or serum by a density gradient preparation, collecting the extracellular vesicles from the separated lipoproteins and extracellular vesicles; isolating and purifying the collected extracellular vesicles by using size exclusion chromatography; treating the isolated and purified extracellular vesicles with an aqueous solution to obtain membranes of the extracellular vesicles, wherein the aqueous solution has a pH in a range of 9 to 14; adding salt in a concentration range between 0.5-2.0M to the aqueous solution; isolating the membranes from the treated extracellular vesicles and identifying proteins on the isolated membranes by employing mass spectrometry.

Methods of diagnosing Crohn’s disease and ulcerative colitis in subjects is provided based on the determination of metabolites in urine samples, such as serine, hypoxanthine, kynurenine, threonine, dimethylglycine, tryptophan, indoxylsul-fate, phenylacetylglutamine, sialic acid, 5-hydroxy-6-indolyl-o-sulfate, 5-(Δ-carboxybutyl) homocysteine, and/or an anion having m/ z:RMT:polarity of 345.1553:0.770:n, or determination of metabolites in stool samples, such as ketodeoxycholic acid, cholic acid, choline, tryptophan, trimethyllysine, serine, butyric acid, lactic acid, hypoxanthine and/or guanine.

The present invention relates to methods and products associated with in vivo enzyme profiling. In particular, the invention relates to methods of in vivo processing of exogenous molecules followed by detection of signature molecules as representative of the presence of active enzymes associated with diseases or conditions. The invention also relates to products, kits, and databases for use in the methods of the invention.

This disclosure relates to new methods for antibody characterization sequencing, such as middle down antibody characterization and sequencing, for example, for de novo antibody sequencing, identifying known antibodies in a sample, or verifying the sequence of antibodies in a sample. In some embodiments, the methods involve exposing antibodies to cathepsin D, cathepsin L, and/or cathepsin D and L, followed by mass spectrometry and sequence identification and deconvolution.

Methods for determining the relative abundance of intact adeno-associated virus (AAV) capsid components in a sample of recombinant AAV particles are disclosed. In embodiments, the methods include a system regeneration process that minimizes or eliminates the presence of ghost peaks to maximize analytical accuracy and ensure product quality and consistency.

The present invention generally pertains to methods of characterizing antibodies and related products. In particular, the present invention pertains to the use of immunoprecipitation and native strong cation exchange chromatography-mass spectrometry to specifically and sensitively detected and quantitate antibodies and related products in a sample.

The present invention generally pertains to methods of characterizing charge variants of a protein. In particular, the present invention pertains to the use of anion exchange chromatography-mass spectrometry (AEX-MS) methods using a salt-gradient. The present invention is particularly useful for charge variant analysis of IgG4 subclasses.

A method for diagnosing the risk of glaucoma development, which can diagnose the risk of glaucoma development at the pre-disease stage, and to provide a new method to diagnose disease progression in the end-stage glaucoma. The method can include, for example, a diagnosing method for the risk of an ocular disease development or for the disease progression of an end-stage ocular disease by molecular profile analysis of the ocular anterior tissue microenvironment, comprising a step of measuring the concentration level of a metabolite appearing in the collected aqueous humor specimens by mass spectrometry (MS).