葡聚糖核盘菌菌丝体和原生质体无细胞提取物中的1,3-β-葡聚糖合酶。

1,3-Beta-glucan synthase in cell-free extracts from mycelium and protoplasts of Sclerotium glucanicum.

作者信息

Kottutz E, Rapp P

机构信息

Institut für Biochemie und Biotechnologie, Technischen Universität Braunschweig, FRG.

出版信息

J Gen Microbiol. 1990 Aug;136(8):1517-23. doi: 10.1099/00221287-136-8-1517.

DOI:10.1099/00221287-136-8-1517

PMID:2148180

Abstract

Conditions for obtaining stable protoplasts from Sclerotium glucanicum and their reversion to hyphal growth were determined. 1,3-beta-Glucan synthase activity was detected in particulate enzyme fractions from mycelium and protoplasts of Scl. glucanicum. UDP-[U-14C]glucose was linearly incorporated into a beta-glucan for about 20 min at 25 degrees C. Optimum pH and temperature values, as well as thermal stabilities of the 1,3-beta-glucan synthase activity, were determined. High concentrations of EDTA were inhibitory. Enzyme activity was stimulated by ATP and GTP. The apparent Km value for UDP-glucose was 0.54 mM. The reaction product was characterized as 1,3-beta-glucan by 13C NMR spectroscopy and hydrolysis products of an exo-1,3-beta-glucanase.

摘要

确定了从葡糖核盘菌获得稳定原生质体的条件及其恢复为菌丝生长的条件。在葡糖核盘菌的菌丝体和原生质体的颗粒酶组分中检测到1,3-β-葡聚糖合酶活性。在25℃下，UDP-[U-¹⁴C]葡萄糖以线性方式掺入β-葡聚糖中约20分钟。确定了1,3-β-葡聚糖合酶活性的最佳pH值和温度值以及热稳定性。高浓度的EDTA具有抑制作用。ATP和GTP可刺激酶活性。UDP-葡萄糖的表观Km值为0.54 mM。通过¹³C NMR光谱和外切1,3-β-葡聚糖酶的水解产物将反应产物表征为1,3-β-葡聚糖。