Peptide aptamer for specific recognition of arginine and its application

Abstract

A peptide aptamer for specific recognition of arginine and its application are provided. The sequence of the peptide aptamer is shown in SEQ ID No. 1. The peptide aptamer is modified by a group that improves stability, or by a fluorescent group, an isotope and an electrochemical group that provide a detection signal, or by an affinity ligand and a mercapto. According to the computer-aided molecular docking simulation prediction, the peptide aptamer that can specifically bind to L-arginine is screened, which is verified by an isothermal titration calorimeter. The peptide aptamer has the advantages of good stability, strong binding ability, high specificity and low production cost.

Claims

1. A peptide aptamer for specific recognition of arginine, the peptide aptamer consisting of the amino acid sequence as set forth in SEQ ID No. 1.

2. An arginine detection kit comprising: an arginine test paper comprising the peptide aptamer according to claim 1 or an arginine detection biosensor comprising the peptide aptamer according to claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a flow chart showing prediction and screening of a peptide aptamer-based on a molecular docking simulation.

(2) FIG. 2 is a diagram showing a data simulation result of a binding verification of the peptide aptamer of the present invention with L-arginine.

DETAILED DESCRIPTION OF THE EMBODIMENTS

(3) Molecular simulation and binding verification of a peptide aptamer with L-arginine A) Molecular simulation of the peptide aptamer and the L-arginine: AutoDock is used to place the L-arginine on the active site of the peptide aptamer, and its binding mode is predicted. The predicted binding parameters of the L-arginine and the peptide aptamer is obtained, and the binding energy is −3.82 kcal/mol. While other amino acids having a similar structure to the L-arginine have no binding ability with the peptide aptamer. B) Binding verification of the simulated peptide aptamer with the L-arginine by the isothermal titration calorimeter C) The sequence of the peptide aptamer used in the binding verification is shown in SEQ ID No.1. A solution with a concentration of 10 μM is prepared by 10 mM PBS. 100 μL of the solution is put into a syringe of the isothermal titration calorimeter (FIG. 1), and 360 μL of 1 μM L-arginine is added to a titration cell for titration. The temperature is set at 37° C., and 25 drops are titrated with each drop of 4 μL. The results of the binding verification are shown in FIG. 2. The results show that the binding parameter Kd value of the peptide aptamer and the L-arginine is 1.334×10.sup.−5 M. The isotherm titration calorimeter is used to determine that the peptide aptamer has no or very weak binding ability to other amino acids having a similar structure to the L-arginine.