5YH4

Miraculin-like protein from Vitis vinifera

Summary for 5YH4

• Entry DOI: 10.2210/pdb5yh4/pdb
• Descriptor: mirauclin-like protein, 1,2-ETHANEDIOL (3 entities in total)
• Functional Keywords: protease inhibitor, beta-trefoil fold, kunitz superfamily, miraculin, hydrolase inhibitor
• Biological source: Vitis vinifera (Grape)
• Total number of polymer chains: 1
• Total formula weight: 20313.98

Authors

Shimizu-Ibuka, A.,Furukawa, N. (deposition date: 2017-09-27, release date: 2018-10-03, Last modification date: 2024-11-13)

Primary citation

Ohkura, S.I.,Hori, M.,Saitoh, K.,Okuzawa, T.,Okamoto, I.,Furukawa, N.,Shimizu-Ibuka, A.
Structural and functional analysis of miraculin-like protein from Vitis vinifera.
Biochim Biophys Acta Proteins Proteom, 1866:1125-1130, 2018

PubMed Abstract: The so-called miraculin-like proteins (MLPs) are homologous to miraculin, a homodimeric protein with taste-modifying activity that converts sourness into sweetness. The identity between MLPs and miraculin generally ranges from 30% to 55%, and both MLPs and miraculin are categorized into the Kunitz-type soybean trypsin inhibitor (STI) family. MLP from grape (Vitis vinifera; vvMLP) exhibits significant homology to miraculin (61% identity), suggesting that vvMLP possesses miraculin-like properties. The results of size-exclusion chromatography and sensory analysis illustrated that vvMLP exists as a monomer in solution with no detectable taste-modifying activity. Crystal structure determination revealed that vvMLP exists as a β-trefoil fold, similarly as other MLPs and Kunitz-type protein inhibitors. The conformation of the loops, including the so-called reactive loop in the STI family, was substantially different between vvMLP and STI. Recombinant vvMLP had inhibitory activity against trypsin (K = 13.7 μM), indicating that the protein can act as a moderate trypsin inhibitor.

PubMed: 30282610
DOI: 10.1016/j.bbapap.2018.08.009

Experimental method

X-RAY DIFFRACTION (1.3 Å)