Eom S et al. (2023), Molecular Mechanism of L-Pyroglutamic Acid Inte...

XB-ART-59639

J Microbiol Biotechnol 2023 Feb 28;332:203-210. doi: 10.4014/jmb.2212.12007.

Show Gene links Show Anatomy links

Molecular Mechanism of L-Pyroglutamic Acid Interaction with the Human Sour Receptor.

Eom S , Lee S , Lee J , Pyeon M , Yeom HD , Song JH , Choi EJ , Lee M , Lee JH , Chang JY .

???displayArticle.abstract???
Taste is classified into five types, each of which has evolved to play its respective role in mammalian survival. Sour taste is one of the important ways to judge whether food has gone bad, and the sour taste receptor (PKD2L1) is the gene behind it. Here, we investigated whether L-pyroglutamic acid interacts with sour taste receptors through electrophysiology and mutation experiments using Xenopus oocytes. R299 of hPKD2L1 was revealed to be involved in L-pyroglutamic acid binding in a concentration-dependent manner. As a result, it is possible to objectify the change in signal intensity according to the concentration of L-pyroglutamic acid, an active ingredient involved in the taste of kimchi, at the molecular level. Since the taste of other ingredients can also be measured with the method used in this experiment, it is expected that an objective database of taste can be created.

???displayArticle.pubmedLink??? 36655284
???displayArticle.pmcLink??? PMC9998207
???displayArticle.link??? J Microbiol Biotechnol

Species referenced: Xenopus laevis
Genes referenced: bad dtl pkd2l1

???attribute.lit??? ???displayArticles.show???

	Graphical Abstract
	Fig. 1. Confirmation of interaction between LPGA and hPKD2L1. (A) The chemical structure of LPGA. (B) Confirmation of proton concentration-dependent activity of hPKD2L1. (C) By applying proton and LPGA to non-injected oocyte, it was confirmed that no activity was shown in non-injected oocytes. (D) In oocytes injected with hPKD2L1 and expressed, activity by proton and LPGA is shown. The scaling bar and each applied pH are displayed at the top side of the current in the figures. All experiments were performed at room temperature, and the holding potential of the protocol used in the experiments was -80 mV. (n = 6-8, obtained from four different oocytes)
	Fig. 2. Confirmation of LPGA's activation manner on hPKD2L1. (A) Confirm whether this activity has concentration-dependent by applying various concentrations of LPGA to hPKD2L1. (B) The sigmoidal graph is shown by normalizing the current shown in 2A, the current of 10 mM LPGA was specified as 100%, and pitted using the Hill equation. (C) The current activity of LPGA applied to hPKD2L1 is shown in a vertical bar chart. Each 'n' number is represented by a black rhombus shape and the applied concentration was indicated at the top of the bar. (D) A ramp protocol was performed to confirm the voltage-dependent manner, and the voltage was applied from -100 mV to +60 mV. Each applied concentration is shown in the figure. All experiments were performed at room temperature, and the holding potential of the protocol used in the experiments was -80 mV. (n = 6-8, obtained from four different oocytes)
	Fig. 3. Molecular docking modeling of LPGAs to hPKD2L1. (A) Side views of the docked LPGAs in complex with hPKD2L1. (B) Top views of the docking model. (C) An enlarged view of the red dotted line in Fig. 3A. (D) An enlarged view of the red dotted line in Fig. 3B.
	Fig. 4. The binding pocket and docking results of LPGAs and hPKD2L1. (A) The binding pocket in the hPKD2L1 region of the extracellular domain membrane pocket side. (B) Two-dimensional schematic presentation of the predicted binding mode of LPGAs in the ligand-binding pocket. The ligands and important residues are shown. (C, D) Computational simulated binding interaction of ligand and residues in wild-type and mutants. The replaced mutants showed changes in interaction activities at varying degrees. (C) Interaction between naringin and wild-type hPKD2L1. (D) Interaction between LPGAs and mutant-type hPKD2L1.
	Fig. 5. Confirmation of inward current change through a changing promising binding residue of LPGA in hPKD2L1 mutant-type. (A) Result of applying ND96 (pH4.0) and LPGA to R229A mutant-type by concentration. The scaling bar and each applied pH are displayed at the top side of the current in the figures. (B) Results of normalization of inward current by Fig. 5A that LPGA and comparison with wild-type inward current. This sigmoid graph was pitted by the Hill equation. (C) The inward current of wild-type and mutant-type hPKD2L1 was numerically quantified and expressed as a vertical error-bar chart. Each 'n' number is represented by a black rhombus shape. The p-value is < 0.001 * and < 0. 0.01 . (D) Current of wild-type and mutant-type according to voltage fluctuation from -100 mV to +60 mV through ramp protocol. All experiments were performed at room temperature, and the holding potential of the protocol used in the experiments was - 80 mV. (n = 6-8, obtained from four different oocytes)

References [+] :

Adler, A novel family of mammalian taste receptors. 2000, Pubmed