A method is disclosed for measuring the properties of protein and lipoprotein elements in a sample. The method includes the of placing a small volume of a sample into a NMR instrument tuned to measure a particular nucleus, applying a series of radiofrequency pulses with intermittent delays in order to measure spin-spin and/or spin-lattice relaxation time constants from the time-domain decay of the signal, without the use of chemical shifts and without converting data into the frequency domain by Fourier transform or other means, at least partially suppressing the water signal prior to the beginning of a sequence used to record relaxation time constants in the time domain, optionally utilizing relaxation contrast agents or other chemical additives to perturb the solvent water or other elements of the sample, analyzing the exponentially decaying NMR signal in the time domain using multi-exponential analysis, and comparing differences in the relaxation time constants for lipoprotein- or protein-specific elements within a single human subject, or between subjects, to assess normal and abnormal metabolism reflective of increased disease risk or active disease.

A method for screening a drug for cytochrome P450 (CYP) induction is provided and can include incubating the drug with a microsome-containing biological sample and then quantitating at least one cytochrome P450 isoform. The isoforms can be selected from 2B6, 3A4, 1A2, and 3A5 isoforms. In some embodiments, the method uses liquid chromatography tandem mass spectrometry (LC-MSMS). A quantitated value can be compared to a threshold value and the drug can be determined to exhibit an acceptable CYP induction potential when the quantitated value does not exceed the threshold value. Isolated peptides are also provided.

The invention generally relates to methods for analyzing a metabolite level in a sample. In certain embodiments, methods of the invention may involve obtaining a sample, analyzing the sample using a mass spectrometry technique to determine a level of at least one metabolite in the sample, and correlating the metabolite level with an originating source of the sample, thereby analyzing the sample.

Provided herein are Mycobacterium smegmatis porin nanopores, systems that comprise these nanopores, and methods of using and making these nanopores. Such nanopores may be wild-type MspA porins, mutant MspA porins, wild-type MspA paralog porins, wild-type MspA homolog porins, mutant MspA paralog porins, mutant MspA homolog porins, or single-chain Msp porins. Also provided are bacterial strains capable of inducible Msp porin expression.

According to the present invention, there is provided a method of detecting a complex comprising a membrane protein bound to a therapeutic agent by mass spectrometry. The method comprises: (a) providing a solution comprising a detergent micelle in which said complex is contained; (b) providing a mass spectrometer comprising a nanoelectrospray ionization source, a mass analyzer and a detector; (c) vaporizing the solution using the nanoelectrospray ionization source under conditions such that the complex is released from the micelle; (d) ionizing the complex; (e) resolving the ionized complex using the mass analyzer; and (f) detecting the resolved complex using the detector. Also provided is a solution comprising a detergent micelle in which a complex is contained, wherein the complex comprises a membrane protein bound to a therapeutic agent.

The invention relates to the detection of vitamin D metabolites. In a particular aspect, the invention relates to methods for detecting derivatized vitamin D metabolites by mass spectrometry.

Provided herein are Mycobacterium smegmatis porin nanopores, systems that comprise these nanopores, and methods of using and making these nanopores. Such nanopores may be wild-type MspA porins, mutant MspA porins, wild-type MspA paralog porins, wild-type MspA homolog porins, mutant MspA paralog porins, mutant MspA homolog porins, or single-chain Msp porins. Also provided are bacterial strains capable of inducible Msp porin expression.

Provided herein are systems and methods for enhanced engagement of protein kinases by kinase binding agents. In particular, the engagement of kinases by functional kinase binding agents is enhanced by the co-expression of the kinases with an active variant of KRAS.

Provided herein are systems and methods for enhanced engagement of protein kinases by kinase binding agents. In particular, the engagement of kinases by functional kinase binding agents is enhanced by the co-expression of the kinases with an active variant of KRAS.

A sensor device for magnetic field measurement using optical magnetic resonance measurement (ODMR) includes a sensor device for magnetic field measurement using ODMR, including a diamond having a plurality of nitrogen defects, a laser emitter, a photodetector, and a circuit board. The laser emitter is designed for the fluorescence excitation of the nitrogen defects, and the photodetector is designed to receive fluorescence radiation of the nitrogen defects. The circuit board has a plurality of layers comprising at least one inner layer; the laser emitter is disposed on an upper face of the circuit board; the photodetector is disposed on a lower face of the circuit board; the diamond is disposed in the interior of the circuit board in the plane of extension of the at least one inner layer; and at least one of the layers has current-carrying structures designed to produce a homogeneous magnetic field which is oriented perpendicularly to the layers of the circuit board and which permeates the diamond.