3 results about "Alanine dehydrogenase" patented technology

The application discloses an alanine dehydrogenase mutant, wherein 1-3 amino acids in positions 165, 177, 178, 180, 199, 200, 217, 218, 219, 225, 237 and 238 of the wild-type alanine dehydrogenase amino acid sequence shown in SEQ ID NO. 1 are respectively mutated into one of lysine, arginine, glutamic acid, proline, valine, glycine, alanine and serine. The alanine dehydrogenase mutant has significant preference for NAD(H) analogues, can produce L-alanine or pyruvic acid by using NAD analogues and NADH analogues, and does not cause interference problems. The application further discloses application of the alanine dehydrogenase mutant.

The invention discloses a double-enzyme sensing system for detecting ochratoxin A and application of the double-enzyme sensing system. The invention provides a method for detecting OTA in a to-be-detected sample, which comprises the following steps: A1) carrying out hydrolysis reaction on the to-be-detected sample by using amide hydrolase to obtain a first-step reaction solution; a2) adding phenylalanine dehydrogenase, coenzyme NAD < + > and Glycine into the first-step reaction solution, and reacting again to obtain a second-step reaction solution; adding a color developing agent into the second-step reaction solution, and carrying out color developing reaction to obtain a reaction product; detecting OTA in the sample to be detected according to the reaction product; according to the invention, a novel OTA degrading enzyme ThADH of an OTA sensing element and a product L-phenylalanine sensing element phenylalanine dehydrogenase are combined, and efficient, visual and quantitative detection of OTA is realized by using a color reaction in a product catalysis process.

The invention discloses a colorimetric biosensing system based on phenylalanine dehydrogenation, which is used for detecting ochratoxin A. The invention provides a method for detecting OTA in a to-be-detected sample, which comprises the following steps: A1) carrying out hydrolysis reaction on the to-be-detected sample by using amide hydrolase VeADH to obtain a first-step reaction solution; a2) adding phenylalanine dehydrogenase, coenzyme NAD < + > and Glycine into the first-step reaction solution, and reacting again to obtain a second-step reaction solution; adding a color developing agent into the second-step reaction solution, and carrying out color developing reaction to obtain a reaction product; detecting OTA in the sample to be detected according to the reaction product; according to the invention, a novel OTA degrading enzyme VeADH of an OTA sensing element and a product L-phenylalanine sensing element phenylalanine dehydrogenase are combined, and efficient, visual and quantitative detection of OTA is realized by using a color reaction in a product catalysis process.