Modified Leucine Dehydrogenase

• Main Authors: MIZUKOSHI TOSHIMI, TAGAMI UNO, HOSHINO WATARU, KODAMA YUYA
• Format: Patent
• Language: Chinese; English
• Published: 15.08.2017
• Subjects: BEER; BIOCHEMISTRY; CHEMISTRY; COMPOSITIONS OR TEST PAPERS THEREFOR; COMPOSITIONS THEREOF; CONDITION-RESPONSIVE CONTROL IN MICROBIOLOGICAL ORENZYMOLOGICAL PROCESSES; CULTURE MEDIA; ENZYMOLOGY; FERMENTATION OR ENZYME-USING PROCESSES TO SYNTHESISE A DESIREDCHEMICAL COMPOUND OR COMPOSITION OR TO SEPARATE OPTICAL ISOMERSFROM A RACEMIC MIXTURE; INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASURING; MEASURING OR TESTING PROCESSES INVOLVING ENZYMES, NUCLEICACIDS OR MICROORGANISMS; METALLURGY; MICROBIOLOGY; MICROORGANISMS OR ENZYMES; MUTATION OR GENETIC ENGINEERING; PHYSICS; PROCESSES OF PREPARING SUCH COMPOSITIONS; PROPAGATING, PRESERVING OR MAINTAINING MICROORGANISMS; SPIRITS; TESTING; VINEGAR; WINE

The present invention provides a means and method useful for measurement of a total branched-chain amino acid concentration. Specifically, the present invention provides a modified enzyme in which at least one amino acid residue is mutated so as to improve a property of a leucine dehydrogenase which is associated with the measurement of the total branched-chain amino acids, such as, for example, substrate specificities of leucine dehydrogenase for total branched-chain amino acids, activity of leucine dehydrogenase for any branched-chain amino acids, and thermal stability of leucine dehydrogenase; and a method of analyzing the total branched-chain amino acids, comprising measuring the total branched-chain amino acids contained in a test sample using the modified enzyme. 本发明提供用于测定总支链氨基酸浓度的手段和方法。具体而言,本发明提供经修饰的酶，其中至少个氨基酸残基被突变，以改善与总支链氨基酸的测定相关联的亮氨酸脱氢酶的特性，(例如，所述亮氨酸脱氢酶对总支链氨基酸的底物特异性,所述亮氨酸脱氢酶对任意支链氨基酸的活性,和亮氨酸脱氢酶的热稳定性)；以及分析总支链氨基酸的方法,包括利用所述的经修饰的酶测定试验样品中包含的总支链氨基酸。