Characterization of a potentially microcystin-producing Fischerella sp. isolated from Ajigol wetland of Iran

Ajigol wetland is a complex ecosystem in Northern Iran, which is ecologically important because contains up to 50% of threatened native plant species and aquatic organisms. Increasing of fish death and animal poison-ings has led to an increased research interest and public awareness of harmful cyanobacterial blooms in this area. In the present work, we characterized a filamentous heterocyst-forming cyanobacterium morphologi-cally and molecularly. Coupled with the 16S rRNA gene sequence, the rbcL gene and the 16S-23S internal transcribed spacer (ITS) secondary structures were analysed. Further, sequences of the mcyD and mcyG genes of microcystin synthetase (mcy) cluster were PCR amplified and sequenced. The secondary structures of the D1-D1' BOX-B and V3 regions provided a better resolution of the studied strain. The sequenced mcy genes involved in the microcystin synthesis contribute to extend the understanding of the evolution of mcy genes in the genus Fischerella. (C) 2020 SAAB. Published by Elsevier B.V. All rights reserved.

Automated summary

This study characterized a filamentous heterocyst-forming cyanobacterium in Ajigol wetland in Northern Iran, focusing on its morphological and molecular features, including the sequences and secondary structures of key genes involved in microcystin synthesis. The findings contribute to a better understanding of the evolution of mcy genes in the genus Fischerella.