非产黄曲霉毒素寄生曲霉无细胞提取物的酶组成在黄曲霉毒素生物合成后期的比较。

Comparison of the enzymatic composition of cell-free extracts of non-aflatoxigenic Aspergillus parasiticus with respect to late stages of aflatoxin biosynthesis.

作者信息

Bhatnagar D, Cleveland T E, Lax A R

出版信息

Arch Environ Contam Toxicol. 1989 May-Jun;18(3):434-8. doi: 10.1007/BF01062370.

Abstract

Cell-free extracts of fungal mycelia of two non-aflatoxigenic isolates of Aspergillus parasiticus (SRRC 163 and SRRC 2043) were examined for enzyme activities involved in the latter stages of aflatoxin biosynthesis. Post-microsomal fractions (105 Kxg supernatant) of both SRRC 163 (ATTC 56774) and SRRC 2043 were able to convert sterigmatocystin (ST) to O-methylsterigmatocystin (OMST); whereas the microsomal (105 Kxg pellet) preparation of only SRRC 163 was able to convert OMST to aflatoxin B1 (AFB1). A mixture of the microsomal fraction of SRRC 163 and post-microsomal fraction of SRRC 2043 converted ST to AFB1. Electrophoretic protein separations of the microsomal fractions of the two A. parasiticus isolates on non-denaturing or denaturing polyacrylamide gel electrophoresis (PAGE) provided equivalent protein profiles.

摘要

对寄生曲霉两个非产黄曲霉毒素分离株（SRRC 163和SRRC 2043）的真菌菌丝体无细胞提取物进行了黄曲霉毒素生物合成后期相关酶活性的检测。SRRC 163（ATCC 56774）和SRRC 2043的微粒体后组分（105 Kxg上清液）均能够将柄曲霉素（ST）转化为O - 甲基柄曲霉素（OMST）；而只有SRRC 163的微粒体制备物（105 Kxg沉淀）能够将OMST转化为黄曲霉毒素B1（AFB1）。SRRC 163的微粒体组分与SRRC 2043的微粒体后组分的混合物能够将ST转化为AFB1。对这两个寄生曲霉分离株的微粒体组分在非变性或变性聚丙烯酰胺凝胶电泳（PAGE）上进行电泳蛋白质分离，得到了相同的蛋白质图谱。