Biodegradation of microcystins by aquatic Burkholderia sp. from a South Brazilian coastal lagoon.
Biological degradation of cyanobacterial hepatotoxin microcystins in estuarine and coastal water samples from the Patos Lagoon estuarine system, a coastal lagoon situated at the southernmost region of Brazil, was observed. Samples of natural surface water were spiked with purified and semi-purified microcystins (MC-LR and [D-Leu(1)]MC-LR) and their concentrations were monitored by HPLC analysis. After 15 days, the toxins were no longer detectable and after 43 days less than 90% of the initial concentration added to the samples was detected by ELISA. The average degradation rates and the exponential decay rate constants from inside and outside of the estuary were similar. A microcystin degradative bacterium was isolated from the estuarine region. Partial sequence of the 16S rDNA showed a 96% homology with the Burkholderia genus. This genus belongs to the beta subdivision on proteobacteria. This is the first report showing the genus Burkholderia as a cyanobacterial toxin degrader.
Lemes
Gilmar A F
GA
Fundação Universidade Federal do Rio Grande (FURG), Av. Itália Km 08, 96201-900 Rio Grande-RS, Brazil.
Kersanach
Ralf
R
Pinto
Luciano da S
Lda S
Dellagostin
Odir A
OA
Yunes
João S
JS
Matthiensen
Alexandre
A
D001673:Biodegradation, Environmental; D001938:Brazil; D019117:Burkholderia / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism*; D004269:DNA, Bacterial / Q000235:genetics / Q000302:isolation & purification; D005618:Fresh Water / Q000382:microbiology; D005843:Geography; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D052998:Microcystins / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D013696:Temperature
D004269:DNA, Bacterial; D052998:Microcystins; C078588:microcystin