Microbiología Industrial y Biotecnología, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956 6° piso (1113), Buenos Aires, Argentina.
Microb Cell Fact. 2008 May 27;7:17. doi: 10.1186/1475-2859-7-17.
Tropane alkaloids, mainly hyoscyamine and scopolamine, are widely used in medicine due to their anticholinergic activity. Scopolamine has a higher demand being the more valuable alkaloid due to its fewer side effects and higher physiological activity. Anisodamine (6beta-hydroxyhyoscyamine) is the intermediate in the conversion of hyoscyamine into scopolamine. Current studies report that this alkaloid is potentially applicable in medicine. The gene that codifies for Hyoscyamine 6-beta hydroxylase, the enzyme responsible for hyoscyamine hydroxylation and epoxidation, leading to scopolamine was isolated from Brugmansia candida.
The h6hcDNA was cloned into pYES2.1 and pYES2.1/V5-His-TOPO vectors to produce an untagged and a tagged protein, respectively. The H6H enzyme was produced in Saccharomyces cerevisiae in order to obtain a biological catalyst for potential industrial applications. Protein extracts of the induced yeast were analyzed by Western blot. The expression was detected 4 h after induction and no degradation was observed during the period assayed. The tagged and the untagged proteins were able to transform hyoscyamine, showing a functional expression of the h6hcDNA.
The strains obtained in this work are promising and potentially applicable in biocatalytic processes.
托烷生物碱,主要是莨菪碱和东莨菪碱,由于其抗胆碱能活性,在医学中被广泛应用。由于其副作用较少且生理活性较高,东莨菪碱的需求更高,是更有价值的生物碱。山莨菪碱(6β-羟基莨菪碱)是莨菪碱转化为东莨菪碱的中间产物。目前的研究报告表明,这种生物碱在医学上具有潜在的应用价值。编码莨菪碱 6-β羟化酶的基因(负责莨菪碱羟化和环氧化,导致东莨菪碱)已从白花曼陀罗中分离出来。
h6hcDNA 被克隆到 pYES2.1 和 pYES2.1/V5-His-TOPO 载体中,分别产生未标记和标记的蛋白质。为了获得潜在工业应用的生物催化剂,在酿酒酵母中生产 H6H 酶。诱导酵母的蛋白提取物通过 Western blot 进行分析。诱导后 4 小时检测到表达,在测定的时间内没有观察到降解。标记和未标记的蛋白质都能够转化莨菪碱,表明 h6hcDNA 的功能表达。
本工作中获得的菌株具有应用潜力,可应用于生物催化过程。