The present disclosure relates to a composition containing an ultrastable enzyme, methods of using the same for preparing a biological sample for analysis by mass spectrometry, and kits comprising the same. The composition includes an ultrastable enzyme isolated from a hyperthermophilic and/or acidophilic organism and optionally, an acid and an additive. The composition can be used at temperatures ranging from about 50 C. to 110 C., preferably at temperatures ranging from about 70 C. to 100 C. In addition, the composition can be used at pH values ranging from 0.5 to 7, preferably at pH values ranging from 2 to 5.

The present application relates to mass spectrometry methods for use in identifying proteins or other biomolecules which are bound irreversibly by test compounds.

Disclosed are .sup.13C and .sup.15N derivatization reagents and their use for gas chromatography-mass spectroscopy and liquid chromatography/mass spectroscopy chemical identification and quantification.

The present invention relates to methods and compositions for monitoring a cellular membrane or a cellular membrane coated nanoparticle after in vivo administration.

A method of detecting a membrane protein by mass spectrometry comprises: (a) providing a solution comprising a detergent micelle in which said membrane protein is contained; (b) providing a mass spectrometer comprising a nanoelectrospray ionisation source, a mass analyser and a detector; (c) vaporising the solution using the nanoelectrospray ionisation source under conditions such that the membrane protein is released from the micelle; (d) ionising the membrane protein; (e) resolving the ionised membrane protein using the mass analyser; and (f) detecting the resolved membrane protein using the detector; wherein the solution contains a phosphate ester detergent which forms said detergent micelle. Also provided are reagents for use in said method.

The present disclosure features non-canonical or heavy isotope-containing amino acids, where the alpha-amino terminus and/or carboxylic acid terminus is modified with molecular cages. The molecular cage-modified amino acids are precluded from metabolic incorporation into proteins within living bacterial, plant, or mammalian cells, or from cell-free protein expression. Once uncaged, the amino acids are readily recognized by native and/or engineered tRNA synthetases, and can subsequently be incorporated into newly-synthesized proteins during protein translation.

Microorganisms are prolific producers of natural products, a group of molecules that make up the majority of drugs approved by the FDA in the past 35 years. After decades of mining, the low-hanging fruit has been picked and so discovery of drug-like molecules from microorganisms has come to a near-halt. The reason for this lack of productivity is that most biosynthetic pathways that give rise to natural products are not active under typical laboratory growth conditions. These so-called cryptic or silent pathways are a major source of new bioactive molecules and methods that reliably activate them could have a profound impact on drug discovery. Disclosed herein is a rapid genetics-free method for eliciting and detecting cryptic metabolites using an imaging mass spectrometry-based approach. An organism of choice is challenged with elicitors from a small molecule library. The molecules elicited are then imaged by mass spec, which allows for rapid identification of cryptic metabolites. These are then isolated and characterized. Employing the disclosed approach activated production of cryptic glycopeptides from an actinomycete bacterium. The molecules that result, the keratinimicins and keratinicyclins, are metabolites with important structural features. At least two of these, keratinimicins B and C, are highly bioactive against several pathogenic strains. This approach will allow for rapid activation and identification of cryptic metabolites from diverse microorganisms in the future.

The disclosed methods are directed to preparing and detecting polypeptides using neutrophil elastase, such as human neutrophil elastase. The polypeptides are optionally denatured, reduced, and/or alkylated before being subjected to a first digestion. A second digestion comprises the use of neutrophil elastase, such as human neutrophil elastase. The prepared fragments are then analyzed chromatographically, electrophoretically, or spectrometrically, or a combination of these methods. The methods are especially useful for the preparation of therapeutic polypeptides for analysis, especially those that are not easily cleaved, such as some bi-specific T-cell engager (BiTE) molecules.

The present invention relates to a method, a device, and a kit for detecting a cancer, predicting a cancer risk, determining a cancer stage, determining a cancer prognosis, and/or evaluating the effectiveness of a treatment in a subject by measuring a urinary metabolite in the subject, and a method for testing a cancer.

An object of the present invention is to provide a method for detecting renal cancer, and a reagent that can be used for the method. Provided is a method for detecting renal cancer, which includes measuring the amount of TFPI2 in a sample derived from a patient. An antibody that specifically recognizes NT-TFPI2 and intact TFPI2 is included in a detection reagent for renal cancer.