【摘要】 白天麻(Gastrodia elata)顶生球茎中分离并纯化了一种抗真菌蛋白(Gastrodia Antifungal Protein),简称GAFP。在马铃薯葡糖琼脂培养基上,4μg GAFP滴加在直径0.6 cm圆纸片上可明显抑制木霉(Trichoderma reesei)菌丝生长。从每千克鲜球茎中可分离得GAFP约20 mg。用SDS-PAGE和凝胶过滤层析测得该蛋白为单多肽链,分子量14.0kD;用离子交换结合法测得电点为8.1;富含Asn,Ala,Gly和Leu,但无Met,Cys和Pro。未经热变性或SDS处理的GAFP与考马氏亮蓝试剂不发生显色反应。GAFP不具有几丁质酶和β-1,3-葡聚糖酶活性。球茎外层组织富含这种蛋白,内层薄壁组织无此蛋白。认为GAFP在阻止真菌侵染当年生顶生和侧生球茎的防卫机制中起重要作用。更多还原

【Abstract】 An anti-fungal protein named GAFF was isolated and puriiied from the terminal conn of Gastrodia elata 131. 4 μg of this protein impregnated in a paper disc on potato glucose agar medium inhibited obviously mycelial spread of Trichoderma reessei. About 20 nig of GAFF was obtained from 1 kg of fresh conn. Only the external part of conn contains this protein, whereas no GAFF was delected in inner part of conn. SDS-PAGE and gel filtration on sephadex G50 showed that GAFF is a single polypetide with MW=14.0 kD, and pI=8.1, determined by binding test of the protein on SF-Sephadex C50. The protein is rich in Asn, Gly, Ala and Leu, but lacks Met, Fro and Cys. GAFF can not give colour reaction with Coomassic blue reagent except that the protein is denatured by heat or SDS treatment, ft was shown not to be of exochitinase and β-1, 3- glucauase activity. GAFF is thought to play an important role in the defense mechanism of the yearly terminal conn to prevent the infection of fungi.更多还原