Linden J C, Tanner W, Kandler O
Botanisches Institut der Universität München, München, Germany.
Plant Physiol. 1974 Nov;54(5):752-7. doi: 10.1104/pp.54.5.752.
A glucosyl and a glucosyl-glucan transferase activity from spinach (Spinacia oleracea L. var. Matador) leaves have been partially purified and characterized. The latter activity (fraction 1 after diethylaminoethylcellulose chromatography) is responsible for the transfer of glucosyl as well as of maltosyl, maltotriosyl, and higher homologous residues to glucose giving rise to maltose and the correspondingly larger molecules. This fraction also shows beta-amylase activity. The transfer takes place only to glucose; maltose, as well as other alpha-1,4-glucans, serve as donors. The enzyme fraction 2 is amylase-free and catalyzes only the transfer of glucosyl moieties, again with high acceptor specificity to glucose. Maltose and larger alpha-1, 4-glucans, with the exception of maltotriose and maltotetraose, act as donors. The physiological function of these enzymes may be the formation of oligosaccharide primers for starch synthetase or phosphorylase.
已对菠菜（Spinacia oleracea L. var. Matador）叶片中的一种葡萄糖基转移酶和一种葡萄糖基-葡聚糖转移酶活性进行了部分纯化和表征。后一种活性（二乙氨基乙基纤维素色谱后的第1组分）负责将葡萄糖基以及麦芽二糖基、麦芽三糖基和更高同源残基转移至葡萄糖，生成麦芽糖和相应更大的分子。该组分还表现出β-淀粉酶活性。转移仅发生于葡萄糖；麦芽糖以及其他α-1,4-葡聚糖作为供体。第2酶组分不含淀粉酶，仅催化葡萄糖基部分的转移，同样对葡萄糖具有高受体特异性。麦芽糖和除麦芽三糖和麦芽四糖外的更大α-1,4-葡聚糖作为供体。这些酶的生理功能可能是为淀粉合成酶或磷酸化酶形成寡糖引物。
