Max Rubner-Institut, Federal Research Institute of Nutrition and Food, Department of Safety and Quality of Fruits and Vegetables, Haid-und-Neu-str. 09, 76131 Karlsruhe, Germany.
Int J Food Microbiol. 2013 Aug 1;165(3):246-50. doi: 10.1016/j.ijfoodmicro.2013.05.011. Epub 2013 May 21.
Mycotoxin biosynthesis in Penicillium verrucosum is modulated by different molecular regulation mechanisms. One important mechanism is the HOG1 (high osmolarity glycerol) MAP kinase signaling pathway. In a comparative analysis three different P. verrucosum strains were selected from six strains with different ability to produce the mycotoxins ochratoxin and citrinin. The fungal strains were grown on laboratory medium supplemented with different concentrations of NaCl. It could be shown that there exists an interrelationship between the growth rate, the level of HOG phosphorylation and the mycotoxin biosynthesis under the respective growth condition. The weak to non ochratoxin producing P. verrucosum strain, BFE875, showed only a poor growth rate but the strongest HOG1 phosphorylation; the strong ochratoxin and citrinin producing strain BFE575 showed a reasonable HOG1 phosphorylation with an average growth rate; and the strong ochratoxin and weak citrinin producing strain BFE495 showed only a poor phosphorylation but the highest growth rate in 7days of incubation at 25°C. The magnitude of phosphorylation of the HOG1 protein seems to be inversely correlated with the degree of adaption of the fungus to hyperosmotic growth conditions.
在疣孢青霉中，不同的分子调控机制调节着真菌毒素的生物合成。其中一个重要的机制是 HOG1（高渗透压甘油）MAP 激酶信号通路。在对 6 株具有不同产毒能力（产赭曲霉毒素和桔青霉素）的青霉菌株进行的比较分析中，选择了 3 株不同的疣孢青霉菌株。在添加不同浓度 NaCl 的实验室培养基上培养真菌菌株。结果表明，在各自的生长条件下，生长速度、HOG 磷酸化水平和真菌毒素生物合成之间存在着相互关系。弱产或非产赭曲霉毒素的青霉菌株 BFE875 生长速度较慢，但 HOG1 磷酸化程度最强；强产赭曲霉毒素和桔青霉素的青霉菌株 BFE575 具有合理的 HOG1 磷酸化水平和平均生长速度；而强产赭曲霉毒素和弱产桔青霉素的青霉菌株 BFE495 只有较弱的磷酸化，但在 25°C 孵育 7 天时生长速度最高。HOG1 蛋白磷酸化的程度似乎与真菌适应高渗生长条件的程度呈负相关。
