| Full text | |
| Author(s): |
Total Authors: 3
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| Affiliation: | [1] USP, ESALQ, Dept Ciencias Biol, BR-13418900 Piracicaba, SP - Brazil
[2] Univ Sao Paulo, Dept Bot, IB, BR-05508900 Sao Paulo - Brazil
[3] Univ Sao Paulo, FCF, Dept Anal Clin & Toxicol, BR-05508900 Sao Paulo - Brazil
Total Affiliations: 3
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| Document type: | Journal article |
| Source: | Brazilian Journal of Biology; v. 71, n. 1, p. 209-216, FEB 2011. |
| Web of Science Citations: | 18 |
| Abstract | |
Microcystis Kützing ex Lemmermann is among the genera of cyanobacteria often associated to toxic blooms with the release of microcystins. A gene cluster codes for microcystin synthetases, which are involved in the biosynthesis of this toxin. The aim of the present study was to investigate the genetic diversity of the mcyB gene, specifically the B1 module, in Brazilian strains of Microcystis spp. and its microcystin variants. Broad genetic diversity was revealed in this region. From the phylogenetic analysis, three clusters were obtained that were not related to the geographic origin or morphospecies of the strains, nor with the variant of the microcystin produced. A group of strains that did not produce microcystins was found, despite the presence of the mcyB1 fragment. Eight microcystin isoforms were detected: MC-LR, [D-Asp³]-MC-LR, [Asp³]-MC-LR, MC-RR, [Dha7]-MC-LR, MC-LF, MC-LW and [D-Asp³, EtAdda5]-MC-LH, the latter of which is described for the first time in Brazil. Moreover, five other variants were not identified and indicate being new. (AU) | |