Structure of Haze Forming Proteins in White Wines: Vitis vinifera Thaumatin-Like Proteins

PLoS One

Elizabeth J. Waters¹  Steven C. Van Sluyter²  Matteo Marangon²  Robert I. Menz² 

[1] School of Botany, University of Melbourne, Victoria, Australia;The Australian Wine Research Institute, Adelaide, South Australia, Australia

关键词: Wine;    Protein structure;    Protein structure comparison;    Grapes;    Disulfide bonds;    Crystal structure;    Protein structure determination;    Sequence alignment;   

DOI  :  10.1371/journal.pone.0113757

学科分类：医学（综合）

来源: Public Library of Science

【 摘 要 】

Grape thaumatin-like proteins (TLPs) play roles in plant-pathogen interactions and can cause protein haze in white wine unless removed prior to bottling. Different isoforms of TLPs have different hazing potential and aggregation behavior. Here we present the elucidation of the molecular structures of three grape TLPs that display different hazing potential. The three TLPs have very similar structures despite belonging to two different classes (F2/4JRU is a thaumatin-like protein while I/4L5H and H2/4MBT are VVTL1), and having different unfolding temperatures (56 vs. 62°C), with protein F2/4JRU being heat unstable and forming haze, while I/4L5H does not. These differences in properties are attributable to the conformation of a single loop and the amino acid composition of its flanking regions.

【 授权许可】

CC BY