Jungblut Anne-Dorothee, Neilan Brett A
School of Biotechnology and Biomolecular Sciences, The University of New South Wales, 2052, Sydney, NSW, Australia.
Arch Microbiol. 2006 Mar;185(2):107-14. doi: 10.1007/s00203-005-0073-5. Epub 2006 Jan 10.
The cyanobacterial hepatotoxins, microcystin and nodularin, are produced by a wide range of cyanobacteria. Microcystin production has been reported in the four cyanobacterial orders: Oscillatoriales, Chroococcales, Stigonematales, and Nostocales. The production of nodularin is a distinct characteristic of the Nostocales genus Nodularia. A single rapid method is needed to reliably detect cyanobacteria that are potentially capable of producing these hepatotoxins. To this end, a PCR was designed to detect all potential microcystin and nodularin-producing cyanobacteria from laboratory cultures as well as in harmful algal blooms. The aminotransferase (AMT) domain, which is located on the modules mcyE and ndaF of the microcystin and nodularin synthetase enzyme complexes, respectively, was chosen as the target sequence because of its essential function in the synthesis of all microcystins as well as nodularins. Using the described PCR, it was possible to amplify a 472 bp PCR product from the AMT domains of all tested hepatotoxic species and bloom samples. Sequence data provided further insight into the evolution of the microcystin and nodularin synthetases through bioinformatic analyses of the AMT in microcystin and nodularin synthetases, with congruence between the evolution of 16S rRNA and the AMT domain.
蓝藻肝毒素微囊藻毒素和节球藻毒素由多种蓝藻产生。在四个蓝藻目中均有微囊藻毒素产生的报道，这四个目分别是颤藻目、色球藻目、真枝藻目和念珠藻目。节球藻毒素的产生是念珠藻属节球藻的一个显著特征。需要一种单一的快速方法来可靠地检测可能产生这些肝毒素的蓝藻。为此，设计了一种聚合酶链反应（PCR），用于检测实验室培养物以及有害藻华中所有可能产生微囊藻毒素和节球藻毒素的蓝藻。分别位于微囊藻毒素和节球藻毒素合成酶复合物的mcyE和ndaF模块上的转氨酶（AMT）结构域被选作靶序列，因为它在所有微囊藻毒素和节球藻毒素的合成中具有关键作用。使用所描述的PCR，可以从所有测试的产肝毒素物种和藻华样本的AMT结构域中扩增出一个472 bp的PCR产物。通过对微囊藻毒素和节球藻毒素合成酶中AMT的生物信息学分析，序列数据进一步深入了解了微囊藻毒素和节球藻毒素合成酶的进化，16S rRNA的进化与AMT结构域之间具有一致性。
