The metabolism of the non-proteinogenic amino acid β-N-methylamino-L-alanine (BMAA) in the cyanobacterium Synechocystis PCC6803
The metabolism of the non-proteinogenic amino acid β-N-methylamino-L-alanine (BMAA) in the cyanobacterium Synechocystis PCC6803
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DOI：
10.1016/j.toxicon.2016.03.005
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发表时间：
2016-06-01
期刊：
影响因子：
2.8
通讯作者：
Downing, Timothy Grant
中科院分区：
文献类型：
--
作者：
Downing, Simone;Downing, Timothy Grant
神经毒性氨基酸β-N-甲氨基-L-丙氨酸(BMAA)是蓝藻在氮饥饿条件下产生的一种神经毒性氨基酸，其代谢与细胞氮素调控密切相关。关于这种氨基酸在生产生物体中的代谢或生物合成知之甚少，目前的知识仅限于在二氧化碳存在的情况下氨基甲酸酯加合物的自发形成，在氮缺乏的蓝藻培养物中添加氨后细胞内游离BMAA的快速去除，以及细胞氮状态和BMAA合成之间的联系。这里提供的数据表明，外源BMAA很容易被蓝藻代谢，在此期间，初级氨基迅速转移到其他细胞氨基酸。此外，数据表明，BMAA在蓝藻中通过可逆的转氨基反应进行代谢。这项研究提供了有关BMAA在蓝藻中代谢的新数据，并首次提出了在蓝藻中生物合成BMAA的前体。(C)2016爱思唯尔有限公司。保留所有权利。
The neurotoxic amino acid beta-N-methylamino-L-alanine (BMAA) is produced by cyanobacteria under nitrogen starvation conditions and its metabolism is closely associated with cellular nitrogen control. Very little is known regarding the metabolism or biosynthesis of this amino acid in the producing organisms and current knowledge is limited to the spontaneous formation of carbamate adducts in the presence of aqueous carbon dioxide, the rapid removal of free cellular BMAA upon the addition of ammonia to nitrogen-starved cyanobacterial cultures, and the link between cellular nitrogen status and BMAA synthesis. Data presented here show that exogenous BMAA is readily metabolised by cyanobacteria during which, the primary amino group is rapidly transferred to other cellular amino acids. Furthermore, data suggest that BMAA is metabolised in cyanobacteria via a reversible transamination reaction. This study presents novel data on BMAA metabolism in cyanobacteria and provides the first proposed biosynthetic precursor to BMAA biosynthesis in cyanobacteria. (C) 2016 Elsevier Ltd. All rights reserved.