Equilibrium dynamics of β-N-methylamino-L-alanine (BMAA) and its carbamate adducts at physiological conditions

David Zimmerman, Joy J. Goto, Viswanathan V Krishnan

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

Elevated incidences of Amyotrophic Lateral Sclerosis/Parkinsonism Dementia complex (ALS/PDC) is associated with β-methylamino-L-alanine (BMAA), a non-protein amino acid. In particular, the native Chamorro people living in the island of Guam were exposed to BMAA by consuming a diet based on the cycad seeds. Carbamylated forms of BMAA are glutamate analogues. The mechanism of neurotoxicity of the BMAA is not completely understood, and BMAA acting as a glutamate receptor agonist may lead to excitotoxicity that interferes with glutamate transport systems. Though the interaction of BMAA with bicarbonate is known to produce carbamate adducts, here we demonstrate that BMAA and its primary and secondary adducts coexist in solution and undergoes a chemical exchange among them. Furthermore, we determined the rates of formation/cleavage of the carbamate adducts under equilibrium conditions using two-dimensional proton exchange NMR spectroscopy (EXSY). The coexistence of the multiple forms of BMAA at physiological conditions adds to the complexity of the mechanisms by which BMAA functions as a neurotoxin.

Original languageEnglish (US)
Article numbere0160491
JournalPLoS One
Volume11
Issue number8
DOIs
StatePublished - Aug 1 2016

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Carbamates
carbamates
glutamates
Alanine
alanine
Glutamic Acid
Guam
nonprotein amino acids
Excitatory Amino Acid Agonists
Cycadopsida
neurotoxicity
indigenous peoples
neurotoxins
dementia
Neurotoxins
Amyotrophic Lateral Sclerosis
Glutamate Receptors
Parkinsonian Disorders
Nutrition
Bicarbonates

ASJC Scopus subject areas

  • Agricultural and Biological Sciences(all)
  • Biochemistry, Genetics and Molecular Biology(all)
  • Medicine(all)

Cite this

Equilibrium dynamics of β-N-methylamino-L-alanine (BMAA) and its carbamate adducts at physiological conditions. / Zimmerman, David; Goto, Joy J.; Krishnan, Viswanathan V.

In: PLoS One, Vol. 11, No. 8, e0160491, 01.08.2016.

Research output: Contribution to journalArticle

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