First Report of Cylindrospermopsin Production by Two Cyanobacteria (Dolichospermum mendotae and Chrysosporum ovalisporum) in Lake Iznik, Turkey

Abstract

Cylindrospermopsin (CYN) is a cytotoxic alkaloid produced by cyanobacteria. The distribution of this toxin is expanding around the world and the number of cyanobacteria species producing this toxin is also increasing. CYN was detected for the first time in Turkey during the summer months of 2013. The responsible species were identified as Dolichospermum (Anabaena) mendotae and Chrysosporum (Aphanizomenon) ovalisporum. The D. mendotae increased in May, however, C. ovalisporum formed a prolonged bloom in August. CYN concentrations were measured by LC-MS/MS and ranged from 0.12 µg·mg−1to 4.92 µg·mg−1 as dry weight, respectively. Both species were the only cyanobacteria actively growing and CYN production was attributed solely to these species. Despite CYN production by C. ovalisporum being a well-known phenomenon, to our knowledge, this is the first report of CYN found in D. mendotae bloom.

Molecular detection of hepatotoxic cyanobacteria in inland water bodies of the Marmara Region, Turkey

“…Microcystis species together with P. agardhii formed blooms in eutrophic environment, such as Manyas, Küçükçekmece and Taşkısı Lake. Nostocalen Cyanobacteria species, on the other hand, prefer alkaline, meso-eutrophic waters of İznik Lake (Akçaalan et al, 2009(Akçaalan et al, , 2014b. Especially Nodularia spumigena is an euryhaline species living in hyposaline to brackish waters in Turkey (Kocasari et al, 2015;Kızılkaya et al, 2016).…”

“…resulted in fish mortality in İznik Lake (Albay et al, 2003a). Cyanotoxin research has started at the end of 1990s and increased in recent years (Albay et al, 2003a,b;Albay et al, 2005;Akçaalan et al, 2006Akçaalan et al, , 2014aAkçaalan et al, , 2014bAkçaalan et al, , 2016 It is well known that microscopic identification of cyanobacteria is time consuming and it requires taxonomic expertise. Due to this limitation, molecular tools have been increasingly applied also to environmental studies (Kurmayer and Christiansen, 2009;Bukowska et al, 2014).…”

An overview of diversity, occurrence, genetics and toxin production of bloom-forming Dolichospermum (Anabaena) species

“…Similarly, another large D. spiroides bloom with 70,000 cell mL À1 occurred in eutrophic Yanghe Reservoir, North China, during the summer of 2007 with WT 24.4 8C, and a TN/TP of 16 Hui et al, 2015). D. mendotae, commonly found in meso to eutrophic lakes, was found to dominate in Lake Iznik, a deep lake of Turkey, on 22 May 2013 with abundance of 4.9 Â 10 7 cell L À1 at WT of 20.6 8C and TN of 1.889 mg L À1 (Akcaalan et al, 2014). Dolichospermum flosaquae was abundant in Taihu Lake, the third largest freshwater lake in China, during the period from late fall to spring, with the peak abundance of 4.0 Â 10 7 cpc gene copies L À1 (based on realtime PCR detection) in April 2009 at a time of TN > 4.0 mg L À1 Liu et al, 2014).…”

“…The Dolichospermum species are able to produce various kinds of secondary metabolites, notably toxins; about 25% to 75% of cyanobacterial blooms are toxic in natural waters (Chorus and Bartram, 1999). The toxins can be classified into three different categories by chemical structure: cyclic peptides (microcystin), alkaloids (anatoxin-a, anatoxin-a (S), saxitoxin, and cylindrospermopsin) and lipopolysaccharides (LPS); and four groups according to the target organs: neurotoxins (anatoxin-a, anatoxin-a (S) and saxitoxin), hepatotoxins (microcystin), cytotoxins (cylindrospermopsin), and dermatotoxins (LPS) (Krishnamurthy et al, 1986;Chorus and Bartram, 1999;Stü ken et al, 2009;Al-Tebrineh et al, 2010;Ž egura et al, 2011;Singh and Dhar, 2013;Akcaalan et al, 2014;Corbel et al, 2014;Sanchez et al, 2014). Toxins are synthesized at all stages of cyanobacterial growth and remain mostly in the cell until their release into waters after cell lysis (Sivonen and Jones, 1999).…”

“…Under favorable conditions, Dolichospermum blooms form potential threats to the environment and human health due to their production of various kinds of potent toxins. The reported toxins produced by these species can be categorized by chemical structure into three different groups: cyclic peptides (microcystin), alkaloids (anatoxin-a, anatoxin-a(S), saxitoxin, and cylindrospermopsin) (Carmichael, 1986;Chorus and Bartram, 1999;Stü ken et al, 2009;AlTebrineh et al, 2010;Žegura et al, 2011;Singh and Dhar, 2013;Akcaalan et al, 2014;Corbel et al, 2014;Sanchez et al, 2014) and lipopolysaccharide. In recent decades, eutrophication in waters from anthropogenic activities, combined with global warming, have promoted Dolichospermum blooms to expand both in size and duration (Singh et al, 2010Koreivienė and Kasperovičienė , 2011;Huber et al, 2012;O'Neil et al, 2012;Ciré s et al, 2013;Slim et al, 2014).…”