Key Laboratory of Marine Environmental Sciences and Ecology, Ocean University of China, Qingdao 266100, PR China.
Toxicon. 2010 May;55(5):947-53. doi: 10.1016/j.toxicon.2009.09.023. Epub 2009 Oct 12.
The cyanobacterial neurotoxin, beta-N-methylamino-l-alanine (BMAA), has been suggested as an important environmental factor for neurodegenerative disease such as amyotrophic lateral sclerosis- Parkinsonism dementia complex (ALS/PDC) in Guam. BMAA was detected within the majority of cyanobacterial isolates surveyed in both free and symbiotic cyanobacteria, living in freshwater as well as marine environments. In this study, we report two methods using liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS/MS) each coupled with a different type of hydrophilic interaction liquid chromatography (HILIC) column to detect BMAA. A third method using AQC-derivatized BMAA was also used for comparison. Axenic cultures of Microcystis aeruginosa and Nostoc sp. isolated from Chinese freshwater were analyzed for both free and protein-bound BMAA at the exponential growth stage. Cultures of two strains of M. aeruginosa collected at four growth stages were also analyzed for the presence of BMAA. BMAA was detected in the Nostoc sp. at very low concentrations (<0.07pmoles on column) only when precolumn AQC derivatization was used. No BMAA was detected in the Chinese derived axenic cultures of Microcystis; detection limits for the LC-ESI-MS and LC-ESI-MS/MS without precolumn derivatization were 10ng and 2pg BMAA on column, respectively. We suggest that cyanobacteria grown under some culture conditions may be relatively free of BMAA.
蓝细菌神经毒素β-N-甲基氨基-L-丙氨酸（BMAA）被认为是关岛地区肌萎缩侧索硬化-帕金森病痴呆复合症（ALS/PDC）等神经退行性疾病的一个重要环境因素。在自由态和共生态蓝细菌的大部分分离株中都检测到了 BMAA，这些蓝细菌存在于淡水和海洋环境中。在这项研究中，我们报告了两种使用液相色谱-电喷雾电离质谱（LC-ESI-MS/MS）的方法，每种方法都与不同类型的亲水相互作用液相色谱（HILIC）柱联用，用于检测 BMAA。还使用 AQC 衍生化的 BMAA 进行了第三种方法的比较。对从中国淡水分离出的铜绿微囊藻和念珠藻的无菌培养物在指数生长期进行了游离态和蛋白结合态 BMAA 的分析。还对收集自四个生长阶段的两种铜绿微囊藻菌株的培养物进行了 BMAA 的存在分析。仅当使用柱前 AQC 衍生化时，才能在念珠藻中检测到非常低浓度的 BMAA（柱上<0.07pmoles）。在中国分离的无菌铜绿微囊藻培养物中未检测到 BMAA；未进行柱前衍生化的 LC-ESI-MS 和 LC-ESI-MS/MS 的检测限分别为 10ng 和 2pg 柱上 BMAA。我们认为，在某些培养条件下生长的蓝细菌可能相对不含 BMAA。
