原果胶酶-T：一种能够从甜菜中溶解原果胶的鼠李半乳糖醛酸酶。

Protopectinase-T: a rhamnogalacturonase able to solubilize protopectin from sugar beet.

作者信息

Sakamoto T, Sakai T

机构信息

Department of Agricultural Chemistry, College of Agriculture, University of Osaka Prefecture, Japan.

出版信息

Carbohydr Res. 1994 Jun 2;259(1):77-91. doi: 10.1016/0008-6215(94)84199-3.

DOI:10.1016/0008-6215(94)84199-3

PMID:8039191

Abstract

Protopectinase-T (PPase-T), isolated from the culture broth of Trametes sanguinea, was able to release pectic substances from sugar beet by degrading rhamnogalacturonan. The smallest polysaccharide (SPS) that can serve as a substrate for PPase-T was prepared from sugar beet pulp by extraction with NaOH and digestion with alpha-L-arabinofuranosidase, alpha-L-arabinase, and beta-(1-->4)-D-galactanase. The reaction products of SPS with PPase-T were isolated by chromatography on DEAE-Toyopearl 650M and Toyopearl HW40-S columns, and analyzed by labeling the reducing ends with [3H]NaBH4 and by 13C NMR spectroscopy. The results indicated that PPase-T cleaved galactopyranosyluronic-rhamnopyranosyl linkages in SPS. Moreover, it was confirmed that the chemical structure of SPS contains a backbone based on units of [-->4)-alpha-D-GalpA-(1-->2)-alpha-L-Rha p-(1-->].

摘要

从血红栓菌培养液中分离得到的原果胶酶 -T（PPase -T）能够通过降解鼠李糖半乳糖醛酸聚糖从甜菜中释放果胶物质。能够作为PPase -T底物的最小多糖（SPS）是通过用氢氧化钠提取甜菜粕并经α-L-阿拉伯呋喃糖苷酶、α-L-阿拉伯糖苷酶和β-(1→4)-D-半乳聚糖酶消化而制备的。SPS与PPase -T的反应产物通过在DEAE -Toyopearl 650M和Toyopearl HW40 -S柱上进行色谱分离，并通过用[³H]NaBH₄标记还原端和¹³C NMR光谱进行分析。结果表明，PPase -T切割SPS中的吡喃半乳糖醛酸基-吡喃鼠李糖基键。此外，已证实SPS的化学结构包含基于[→4)-α-D-半乳糖醛酸-(1→2)-α-L-鼠李糖p-(1→]单元的主链。