N-β-Methylamino-L-Alanine and Its Naturally Occurring Isomers in Cyanobacterial Blooms in Lake Winnipeg
- 399 Downloads
Cyanobacterial blooms have affected Lake Winnipeg since the mid-1990s due to an increased phosphorus loading into the lake, which has been exacerbated by stressors such as climate change and eutrophication. Aquatic ecosystems involving cyanobacteria have been found to contain N-β-methylamino-L-alanine (BMAA) and 2,4-diaminobutyric acid (DAB), non-protein amino acids that are associated with neurodegenerative disease, as well as two of the naturally occurring isomers, N-2(amino)ethylglycine (AEG) and β-amino-N-methylalanine (BAMA). We hypothesized that the cyanobacterial bloom in Lake Winnipeg produces BMAA and/or its naturally occurring isomers. Samples of cyanobacteria were collected by the Lake Winnipeg Research Consortium from standard sampling stations and blooms in July and September of 2016 and were analyzed for BMAA, DAB, AEG, and BAMA using previously published validated analytical methods. BMAA and BAMA were found in the highest concentration in the center of the north basin, the deepest and lowest-nitrogen zone of the lake, at an average concentration of 4 μg/g (collected in July and September 2016) and 1.5 mg/g (collected in July 2016), respectively. AEG and DAB were found in the highest concentration in cyanobacterial blooms from the nearshore region of the north basin, the slightly shallower and more nitrogen-rich zone of the lake, at 2.1 mg/g (collected in July 2016) and 0.2 mg/g (collected in July and September 2016), respectively. These findings indicate that the production of non-protein amino acids varies with the depth and nutrient contents of the bloom. It is important to note that we did not measure food or water samples directly and further study of the Lake Winnipeg food web is required to determine whether BMAA bioaccumulation represents an increased risk factor for neurodegenerative disease in the region.
KeywordsN-β-Methylamino-L-alanine (BMAA) Cyanobacterial blooms Lake Winnipeg Neurotoxin
We would like to acknowledge Karen Scott, the Lake Winnipeg Research Consortium, and the crew of the Namao as well as funding from the Natural Sciences and Engineering Research Council of Canada, the Canadian Foundation for Innovation, and the Canada Research Chairs program.
Compliance with Ethical Standards
Conflict of Interest
The authors declare that they have no conflict of interest.
- Baker TC, Tymm FJM, Murch SJ (2017) Assessing environmental exposure to β-N-methylamino-L-alanine (BMAA) in complex sample matrices: a comparison of the three most popular LC-MS/MS methods. Neurotox Res. https://doi.org/10.1007/s12640-017-9764-3
- Brunskill GJ, Elliott SEM, Campbell P (1980) Morphometry, hydrology, and watershed data pertinent to the limnology of Lake Winnipeg. Can Manuscr Rep Fish Aquat Sci 1556:1–32Google Scholar
- Duncan MW (1991) The role of the cycad neurotoxin BMAA in the ALS-PD of the western Pacific. In: Rowland LP (ed) Advances in neurology. Amyotrophic lateral sclerosis and other motor neuron diseases, vol 56. New York, Raven, pp 301–310Google Scholar
- Duncan MW, Kopin IJ, Garruto RM, Lavine L, Markey SP (1988) 2-Amino-3-(methylamino)-propionic acid in cycad-derived foods is an unlikely cause of amyotrophic lateral sclerosis/parkinsonism. Lancet 2:631–632Google Scholar
- Duncan MW, Kopin IJ, Crowley JS, Jones SM, Markey SP (1989) Quantification of the putative neurotoxin 2-amino-3-(methylamino) propanoic acid (BMAA) in cycadales: analysis ofthe seeds of some members of the family Cycadaceae. J Anal Toxicol 13:169–l75Google Scholar
- Environment and Climate Change Canada (2016) Canadian environmental sustainability indicators: nutrients in Lake Winnipeg http://www.ec.gc.ca/indicateurs-indicators/default.asp?lang=en&n=55379785-1
- Environment Canada (2012) Final project reports: Lake Winnipeg Basin Initiative 2008/09–2011/12. https://mspace.lib.umanitoba.ca/xmlui/bitstream/handle/1993/23444/FinalProjectReports_LWpgB_In2008_2012.pdf?sequence=1&isAllowed=y
- Glover WB, Baker TC, Murch SJ, Brown PN (2015) Determination of beta-N-methylamino-L-alanine, N-(2-aminoethyl)glycine, and 2,4-diaminobutyric acid in food products containing cyanobacteria by ultra-performance liquid chromatography and tandem mass spectrometry: single-laboratory validation. J AOAC Int 98:1559–1565CrossRefPubMedGoogle Scholar
- Jiang L, Kiselova N, Rosen J, Ilag LL (2014) Quantification of neurotoxin BMAA (β-N-methylamino-L-alanine) in seafood from Swedish markets. Sci Rep 4(6931):1–7Google Scholar
- Rauk A (2017) Does substitution of BMAA for serine alter conformational dynamics of the amyloid beta peptide of Alzheimer’s disease: molecular dynamics simulations 100th Canadian Chemistry Conference Abstract #00260 http://abstracts.csc2017.ca/00000945.htm
- Scott KJ (2017) Lake Winnipeg Research Consortium Inc. 2016/2017 annual report. http://www.lakewinnipegresearch.org/pdf%20files/LWRC%202016_17%20Programs%20Report%20FINAL.pdf
- Scott KJ, McCullough G, Stainton M, Ayles B, Hann B (2011) Lake Winnipeg-state of science: what is the scientific basis for understanding and protecting Lake Winnipeg? http://www.lakewinnipegresearch.org/pdf%20files/LWRC%202011%20Sci%20WS%20Report_FINAL_web.pdf