Bacteria homologus to Aeromonas capable of microcystin degradation

• Main Authors: Mankiewicz-Boczek J., Gągała I., Jurczak T., Jaskulska A., Pawełczyk J., Dziadek J.
• Format: Article
• Language: English
• Published: De Gruyter 2015-03-01
• Series: Open Life Sciences
• Subjects: microcystins; biodegradation; mlrA gene; Aeromonas; Stenotrophomonas; Sphingopyxis
• Online Access: http://www.degruyter.com/view/j/biol.2015.10.issue-1/biol-2015-0012/biol-2015-0012.xml?format=INT

Water blooms dominated by cyanobacteria are capable of producing hepatotoxins known as microcystins. These toxins are dangerous to people and to the environment. Therefore, for a better understanding of the biological termination of this increasingly common phenomenon, bacteria with the potential to degrade cyanobacteria-derived hepatotoxins and the degradative activity of culturable bacteria were studied. Based on the presence of the mlrA gene, bacteria with a homology to the Sphingopyxis and Stenotrophomonas genera were identified as those presenting potential for microcystins degradation directly in the water samples from the Sulejów Reservoir (SU, Central Poland). However, this biodegrading potential has not been confirmed in in vitro experiments. The degrading activity of the culturable isolates from the water studied was determined in more than 30 bacterial mixes. An analysis of the biodegradation of the microcystin-LR (MC-LR) together with an analysis of the phylogenetic affiliation of bacteria demonstrated for the first time that bacteria homologous to the Aeromonas genus were able to degrade the mentioned hepatotoxin, although the mlrA gene was not amplified. The maximal removal efficiency of MC-LR was 48%. This study demonstrates a new aspect of interactions between the microcystin-containing cyanobacteria and bacteria from the Aeromonas genus.