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  • 1.
    Berntzon, Lotta
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Bergman, Birgitta
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Eriksson, Johan
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Effects of bicarbonate on LC-MS/MS analysis of BMAA using AQC or EZ: FaastTM pre-column derivatizationManuskript (preprint) (Övrigt vetenskapligt)
  • 2.
    Berntzon, Lotta
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Erasmie, Sven
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Celepli, Narin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Eriksson, Johan
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Rasmussen, Ulla
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Bergman, Birgitta
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    BMAA Inhibits Nitrogen Fixation in the Cyanobacterium Nostoc sp PCC 71202013Ingår i: Marine Drugs, ISSN 1660-3397, E-ISSN 1660-3397, Vol. 11, nr 8, s. 3091-3108Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Cyanobacteria produce a range of secondary metabolites, one being the neurotoxic non-protein amino acid beta-N-methylamino-L-alanine (BMAA), proposed to be a causative agent of human neurodegeneration. As for most cyanotoxins, the function of BMAA in cyanobacteria is unknown. Here, we examined the effects of BMAA on the physiology of the filamentous nitrogen-fixing cyanobacterium Nostoc sp. PCC 7120. Our data show that exogenously applied BMAA rapidly inhibits nitrogenase activity (acetylene reduction assay), even at micromolar concentrations, and that the inhibition was considerably more severe than that induced by combined nitrogen sources and most other amino acids. BMAA also caused growth arrest and massive cellular glycogen accumulation, as observed by electron microscopy. With nitrogen fixation being a process highly sensitive to oxygen species we propose that the BMAA effects found here may be related to the production of reactive oxygen species, as reported for other organisms.

  • 3.
    Berntzon, Lotta
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Ronnevi, L. O.
    Bergman, Birgitta
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Eriksson, Johan
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    DETECTION OF BMAA IN THE HUMAN CENTRAL NERVOUS SYSTEM2015Ingår i: Neuroscience, ISSN 0306-4522, E-ISSN 1873-7544, Vol. 292, s. 137-147Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Amyotrophic lateral sclerosis (ALS) is an extremely devastating neurodegenerative disease with an obscure etiology. The amino acid beta-N-methyl-L-alanine (BMAA) produced by globally widespread phytoplankton has been implicated in the etiology of human motor neuron diseases. BMAA was recently proven to be present in Baltic Sea food webs, ranging from plankton to larger Baltic Sea organisms, some serving as important food items (fish) for humans. To test whether exposure to BMAA in a Baltic Sea setting is reflected in humans, blood and cerebrospinal fluid (CSF) from individuals suffering from ALS were analyzed, together with sex- and age-matched individuals not inflicted with ALS. Ultra high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) and multiple reaction monitoring (MRM), in conjunction with diagnostic transitions revealed BMAA in three (12%) of the totally 25 Swedish individuals tested, with no preference for those suffering from ALS. The three BMAA-positive samples were all retrieved from the CSF, while BMAA was not detected in the blood. The data show that BMAA, potentially originating from Baltic Sea phytoplankton, may reach the human central nervous system, but does not lend support to the notion that BMAA is resident specifically in ALS-patients. However, while dietary exposure to BMAA may be intermittent and, if so, difficult to detect, our data provide the first demonstration of BMAA in the central nervous system of human individuals ante mortem quantified with UHPLC-MS/MS, and therefore calls for extended research efforts.

  • 4.
    Eriksson, Johan
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    Protein concentration versus derivatization efficiency2007Ingår i: 4th Symposium “BMAA - occurrence and potential threat to human health”, Stockholm 2007, 2007Konferensbidrag (Övrig (populärvetenskap, debatt, mm))
  • 5.
    Eriksson, Johan
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    Jonasson, Sara
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    Papaefthimiou, Dimitra
    Rasmussen, Ulla
    Bergman, Birgitta
    Improving derivatization efficiency of BMAA utilizing AccQ-Tag ia a complex cyanobacterial matrix2009Ingår i: Amino Acids, ISSN 0939-4451, E-ISSN 1438-2199, nr 36, s. 43-48Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Two different assays have been developed and used in order to investigate the optimal conditions for derivatization and detection of acid β-N-methyl-amino-l-alanine (BMAA) in a cyanobacterial sample. BMAA was extracted from cyanobacterial cultures both from the cytosolic (“free”) fraction and in the precipitated (“protein”) fraction using a newly developed extraction scheme and the sample matrix was standardized according to protein concentration to ensure the highest possible derivative yield. A rapid and sensitive HPLC method for fluorescence detection of the non-protein amino acid BMAA in cyanobacteria, utilizing the Waters AccQ-Tag® chemistry and Chromolith® Performance RP-18e columns was developed. Using this new method and utilizing a different buffer system and column than that recommended by Waters, we decreased the time between injections by 75%. The limit of quantification was determined to be 12 nmol and limit of detection as 120 fmol. The linear range was in the range of 8.5 nmol–84 pmol. Accuracy and precision were well within FDA guidelines for bioanalysis.

  • 6.
    Jiang, Liying
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Eriksson, Johan
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Lage, Sandra
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Jonasson, Sara
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Shams, Shiva
    Mehine, Martin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Ilag, Leopold L.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Rasmussen, Ulla
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Diatoms: A Novel Source for the Neurotoxin BMAA in Aquatic Environments2014Ingår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 9, nr 1, artikel-id e84578Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Amyotrophic lateral sclerosis (ALS) or Lou Gehrig's disease is a neurological disorder linked to environmental exposure to a non-protein amino acid, beta-N-methylamino-L-alanine (BMAA). The only organisms reported to be BMAA-producing, are cyanobacteria - prokaryotic organisms. In this study, we demonstrate that diatoms - eukaryotic organisms - also produce BMAA. Ultra-high-performance liquid chromatography coupled with tandem mass spectrometry revealed the occurrence of BMAA in six investigated axenic diatom cultures. BMAA was also detected in planktonic field samples collected on the Swedish west coast that display an overrepresentation of diatoms relative to cyanobacteria. Given the ubiquity of diatoms in aquatic environments and their central role as primary producers and the main food items of zooplankton, the use of filter and suspension feeders as livestock fodder dramatically increases the risk of human exposure to BMAA-contaminated food.

  • 7.
    Jonasson, Sara
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    Eriksson, Johan
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    Berntzon, Lotta
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    Rasmussen, Ulla
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    Bergman, Birgitta
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    A novel cyanobacterial toxin (BMAA) with potential neurodegenerative effects2008Ingår i: Plant Biotechnology, ISSN 1342-4580, E-ISSN 1347-6114, Vol. 25, nr 3, s. 227-232Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The non-protein amino acid beta-N-methyl-amino-L-alanine (BMAA) is a neurotoxin that was recently found to be produced by most cyanobacteria. The neurotoxin was discovered in 1967 in the seeds of the cycad Cycas micronesica, but this BMAA may originate from the symbiotic cyanobacterium Nostoc, which inhabits the roots of cycads. BMAA is thought to be the cause of the deadly neurodegenerative disease amyotrophic lateral sclerosis/parkinsonism dementia complex (ALS/PDC), common among the Chamorro people of Guam. It was demonstrated that the Chamorros, in all probability, have been exposed to high levels of BMAA through dietary consumption of flying foxes which fed mainly on cycads seeds. BMAA production may be a common conserved evolutionary feature among cyanobacteria and due to their wide global distribution, the toxin may be a common concern and potentially involved in provoking degenerative diseases worldwide. BMAA may likewise be bioaccumulated in other cyanobacterial based food webs within ecosystems outside Guam, and it is proposed that such webs may exist in the Baltic Sea, with its massive occurrence of cyanobacteria (blooms).

  • 8.
    Jonasson, Sara
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    Eriksson, Johan
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    Berntzon, Lotta
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    Spacil, Zdenek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi. Charles University Prague, Czech Republic .
    Ilag, Leopold L.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Ronnevi, Lars-Olof
    Rasmussen, Ulla
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    Bergman, Birgitta
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    Transfer of a cyanobacterial neurotoxin within a temperate aquatic ecosystem suggests pathways for human exposure2010Ingår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 107, nr 20, s. 9252-9257Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    beta-methylamino-L-alanine (BMAA), a neurotoxic nonprotein amino acid produced by most cyanobacteria, has been proposed to be the causative agent of devastating neurodegenerative diseases on the island of Guam in the Pacific Ocean. Because cyanobacteria are widespread globally, we hypothesized that BMAA might occur and bioaccumulate in other ecosystems. Here we demonstrate, based on a recently developed extraction and HPLC-MS/MS method and long-term monitoring of BMAA in cyanobacterial populations of a temperate aquatic ecosystem (Baltic Sea, 2007-2008), that BMAA is biosynthesized by cyanobacterial genera dominating the massive surface blooms of this water body. BMAA also was found at higher concentrations in organisms of higher trophic levels that directly or indirectly feed on cyanobacteria, such as zooplankton and various vertebrates (fish) and invertebrates (mussels, oysters). Pelagic and benthic fish species used for human consumption were included. The highest BMAA levels were detected in the muscle and brain of bottom-dwelling fishes. The discovery of regular biosynthesis of the neurotoxin BMAA in a large temperate aquatic ecosystem combined with its possible transfer and bioaccumulation within major food webs, some ending in human consumption, is alarming and requires attention.

  • 9.
    Lage, Sandra
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Reis Costa, Pedro
    Moita, Teresa
    Eriksson, Johan
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Rasmussen, Ulla
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Jonasson Rydberg, Sara
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    BMAA in shellfish from two Portuguese transitional water bodies suggests the marine dinoflagellate Gymnodinium catenatum as a potential BMAA source2014Ingår i: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 152, s. 131-138Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The neurotoxin -N-methylamino-l-alanine (BMAA) and its putative role in multiple neurodegenera-tive diseases have been intensely studied since 2005 when the toxin was discovered to be producedby worldwide-distributed cyanobacterial species inhabiting terrestrial, marine, brackish, and freshwaterecosystems. Recently, BMAA production was also associated with one eukaryotic group, namely, diatoms,raising questions about its production by other phytoplanktonic groups. To test for BMAA bioavailabilityin ecosystems where abundant phytoplanktonic blooms regularly occur, samples of filter-feeding shell-fish were collected in two Portuguese transitional water bodies. BMAA content in cockles (Cerastodermaedule) collected weekly between September and November 2009 from Ria de Aveiro and at least once amonth from May to November from Ria Formosa, fluctuated from 0.079 ± 0.055 to 0.354 ± 0.066 g/g DWand from below the limit of detection to 0.434 ± 0.110 g/g DW, respectively. Simultaneously to BMAAoccurrence in cockles, paralytic shellfish toxins were detected in shellfish as a result of Gymnodiniumcatenatum blooms indicating a possible link between this marine dinoflagellate and BMAA production.Moreover, considerable high BMAA levels, 0.457 ± 0.186 g/g DW, were then determined in a laboratorygrown culture of G. catenatum. This work reveals for the first time the presence of BMAA in shellfishfrom Atlantic transitional water bodies and consubstantiate evidences of G. catenatum as one of the mainsources of BMAA in these ecosystems.

  • 10.
    Spacil, Zdenek
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Eriksson, Johan
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    Jonasson, Sara
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    Rasmussen, Ulla
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    Ilag, Leopold L.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Bergman, Birgitta
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    Analytical protocol for identification of BMAA and DAB in biologicalsamples2010Ingår i: The Analyst, ISSN 0003-2654, E-ISSN 1364-5528, Vol. 135, s. 127-132Artikel i tidskrift (Refereegranskat)
    Abstract [en]

     

    b

    -N-methylamino-L-alanine (BMAA) is a non-protein amino acid, thought to be inflicting neurodegenerative diseases related to ALS/PDC in human beings. Due to conflicting data concerning the presence of BMAA in various biological matrixes, we present a robust and sensitive method for high confidence identification of BMAA after derivatization by 6-aminoquinolyl-N

    -hydroxysuccinimidyl carbamate (AQC). The efficient sample pretreatment in combination with LC-MS/MS SRM enables chromatographic separation of BMAA from the isomer 2,3-diaminobutyric acid (DAB). The method is applicable for selective BMAA/DAB detection in various biological samples ranging from a prokaryotic cyanobacterium to eukaryotic fish.

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