Sulochrin oxidase, an enzyme catalyzing regio- and stereospecific phenol oxidative coupling reaction to form (+)-bisdechlorogeodin from sulochrin, was isolated from Penicillium frequentans CMI 96659. By chromatographies on DEAE-cellulose, hydroxyapatite, Phenyl-Sepharose, Mono P, Mono Q, and HPLC gel filtration columns, sulochrin oxidase was purified to apparent homogeneity. The purified enzyme had a molecular weight of 230 K as estimated by gel filtration and 110 K as estimated by sodium dodecylsulfate-polyacrylamide gel electrophoresis under denaturing conditions, suggesting that the active enzyme was a homodimer. The enzyme showed pI 4.0 and an optimum pH of 6. The enzyme activity was strongly inhibited by the copper-chelating reagent, diethyldithiocarbamate, and did not recover its full activity even after removing the inhibitor by dialysis. However, enzyme activity was fully restored by the addition of Cu2+. Thus, sulochrin oxidase is considered to be a copper protein. The enzyme showed high substrate specificity for benzophenone compounds such as sulochrin and dihydrogeodin.
Dihydrogeodin oxidase (DHGO), an enzyme catalyzing regio- and stereo-specific intramolecular phenol oxidative coupling reaction of dihydrogeodin to give (+)-geodin, was purified up to homogeneity. DHGO was shown to be a blue copper protein with an absorption maximum at 600 nm. The presence of copper atoms was confirmed by atomic absorption analysis. A molecular weight of 153, 000 was estimated for the oxidase and it was composed of two equal molecular weight subunits. DHGO had no phenolase activity and showed strict substrate specificity.
Fungal artificial chromosomes, compositions, methods and uses therefor
申请人:Intact Genomics, Inc
公开号:US10337019B2
公开(公告)日:2019-07-02
Fungal artificial chromosome (FAC) vectors are disclosed. A vector can be replicated in a bacterial or a fungal host, and can comprise an insert of heterologous DNA up to about 500 kilobases. A vector can be used for cloning and expressing a secondary metabolite (SM) gene cluster. An insert sequence can be modified by homologous recombination. A vector can be a plasmid comprising bacterial and fungal origins of replication, as well as bacterial and fungal selection marker genes. Also disclosed are vectors that can be integrated into a fungal genome, and dual function vectors which can be replicated in a bacterial or a fungal host and can also be integrated into a fungal genome. Also disclosed are methods of generating plasmid libraries including vectors comprising intact SM gene clusters.
本文公开了真菌人工染色体(FAC)载体。载体可在细菌或真菌宿主中复制,并可包含高达约 500 千碱基的异源 DNA 插入物。载体可用于克隆和表达次级代谢物(SM)基因簇。插入序列可通过同源重组进行修饰。载体可以是包含细菌和真菌复制起源以及细菌和真菌选择标记基因的质粒。还公开了可整合到真菌基因组中的载体,以及可在细菌或真菌宿主中复制并可整合到真菌基因组中的双功能载体。还公开了生成质粒文库的方法,包括包含完整 SM 基因簇的载体。