Biomaterial Database

Protein amino acid analysis by an isotope ratio gas chromatography mass spectrometry computer technique. 1979

J J Rafter, and M Ingelman-Sundberg, and J A Gustafsson

A method for quantitative analysis of protein amino acids by a gas chromatography mass spectrometry computer system is described. Amino acids were analysed as their N-trifluoroacetyl n-butyl ester derivatives. Isotope ratio determination was used as the quantitating technique via multiple internal standards. The exact composition of a deuterated amino acid mixture was determined against a standard amino acid calibration mixture and in turn the protein amino acid composition was determined against the deuterated amino acid mixture. The amount of protein taken for analysis was 100 micrograms and the procedure, excluding hydrolysis, could be performed with 2 1/2 hours. The introduction of the internal standards prior to protein hydrolysis provides a method with good precision (mean coefficient of variation less than 5%). The method, tested on insulin, gave results which agreed well with the known composition of the protein and with simultaneous analysis on ion exchangers.

UI	MeSH Term	Description	Entries
D007328	Insulin	A 51-amino acid pancreatic hormone that plays a major role in the regulation of glucose metabolism, directly by suppressing endogenous glucose production (GLYCOGENOLYSIS; GLUCONEOGENESIS) and indirectly by suppressing GLUCAGON secretion and LIPOLYSIS. Native insulin is a globular protein comprised of a zinc-coordinated hexamer. Each insulin monomer containing two chains, A (21 residues) and B (30 residues), linked by two disulfide bonds. Insulin is used as a drug to control insulin-dependent diabetes mellitus (DIABETES MELLITUS, TYPE 1).	Iletin,Insulin A Chain,Insulin B Chain,Insulin, Regular,Novolin,Sodium Insulin,Soluble Insulin,Chain, Insulin B,Insulin, Sodium,Insulin, Soluble,Regular Insulin
D011506	Proteins	Linear POLYPEPTIDES that are synthesized on RIBOSOMES and may be further modified, crosslinked, cleaved, or assembled into complex proteins with several subunits. The specific sequence of AMINO ACIDS determines the shape the polypeptide will take, during PROTEIN FOLDING, and the function of the protein.	Gene Products, Protein,Gene Proteins,Protein,Protein Gene Products,Proteins, Gene
D002849	Chromatography, Gas	Fractionation of a vaporized sample as a consequence of partition between a mobile gaseous phase and a stationary phase held in a column. Two types are gas-solid chromatography, where the fixed phase is a solid, and gas-liquid, in which the stationary phase is a nonvolatile liquid supported on an inert solid matrix.	Chromatography, Gas-Liquid,Gas Chromatography,Chromatographies, Gas,Chromatographies, Gas-Liquid,Chromatography, Gas Liquid,Gas Chromatographies,Gas-Liquid Chromatographies,Gas-Liquid Chromatography
D003201	Computers	Programmable electronic devices designed to accept data, perform prescribed mathematical and logical operations at high speed, and display the results of these operations.	Calculators, Programmable,Computer Hardware,Computers, Digital,Hardware, Computer,Calculator, Programmable,Computer,Computer, Digital,Digital Computer,Digital Computers,Programmable Calculator,Programmable Calculators
D003903	Deuterium	The stable isotope of hydrogen. It has one neutron and one proton in the nucleus.	Deuterons,Hydrogen-2,Hydrogen 2
D000596	Amino Acids	Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.	Amino Acid,Acid, Amino,Acids, Amino
D013058	Mass Spectrometry	An analytical method used in determining the identity of a chemical based on its mass using mass analyzers/mass spectrometers.	Mass Spectroscopy,Spectrometry, Mass,Spectroscopy, Mass,Spectrum Analysis, Mass,Analysis, Mass Spectrum,Mass Spectrum Analysis,Analyses, Mass Spectrum,Mass Spectrum Analyses,Spectrum Analyses, Mass