TY - JOUR
T1 - Microcystis toxigenic strains in urban lakes
T2 - A case of study in Mexico City
AU - Arzate-Cárdenas, Mario Alberto
AU - Olvera-Ramírez, Roxana
AU - Martínez-Jerónimo, Fernando
N1 - Funding Information:
Acknowledgments M. A. Arzate-Cárdenas thanks Consejo Nac-ional de Ciencia y Tecnología (CONACYT) for the fellowship to perform graduate studies (No. 205163). Authors thank the Instituto Politécnico Nacional (IPN) and, particularly, the Secretaría de Investigación y Posgrado, the Sistema de Estímulo al Desempeño de los Investigadores and the Comisión de Operación y Fomento de Actividades Académicas del IPN for the support received to perform this study. We also thank Ms. Ingrid Mascher for editorial assistance with the English version of this manuscript. Thanks are due to two anonymous reviewers for their critical observations and comments that improved substantially this paper.
PY - 2010/8
Y1 - 2010/8
N2 - Microcystis is a bloom-forming, common cyanobacterium in urban lakes of Mexico City. To assess the presence of potentially cyanotoxin-producing Microcystis, molecular techniques were applied and acute toxicity bioassays were performed with Daphnia magna neonates exposed to cyanobacterial crude extracts. Toxigenic potential of isolated strains was inferred by amplifying the mcyA-Cd genes and their identity as Microcystis was confirmed through the 16S rDNA and phycocyanin operon amplification. Microcystins synthesized under culture conditions were quantified through ELISA. The acute toxicity bioassays revealed that mortality was independent from the cyanotoxin concentration in some strains; this suggests the presence of other metabolites (different from microcystins) that also exerted an important biological effect. Isolated strains had the mcyA-Cd gene and most of them produced variable amounts of microcystins in the culture conditions used, confirming their toxigenic potential. Results warn about possible toxic effect risks for aquatic biota, neighboring areas, visitors and users of these sites, due to the constant presence of these blooms in the studied water bodies.
AB - Microcystis is a bloom-forming, common cyanobacterium in urban lakes of Mexico City. To assess the presence of potentially cyanotoxin-producing Microcystis, molecular techniques were applied and acute toxicity bioassays were performed with Daphnia magna neonates exposed to cyanobacterial crude extracts. Toxigenic potential of isolated strains was inferred by amplifying the mcyA-Cd genes and their identity as Microcystis was confirmed through the 16S rDNA and phycocyanin operon amplification. Microcystins synthesized under culture conditions were quantified through ELISA. The acute toxicity bioassays revealed that mortality was independent from the cyanotoxin concentration in some strains; this suggests the presence of other metabolites (different from microcystins) that also exerted an important biological effect. Isolated strains had the mcyA-Cd gene and most of them produced variable amounts of microcystins in the culture conditions used, confirming their toxigenic potential. Results warn about possible toxic effect risks for aquatic biota, neighboring areas, visitors and users of these sites, due to the constant presence of these blooms in the studied water bodies.
KW - Acute toxicity
KW - Cladocera
KW - Cyanobacteria
KW - Microcystins
KW - Molecular markers
UR - http://www.scopus.com/inward/record.url?scp=79952335272&partnerID=8YFLogxK
U2 - 10.1007/s10646-010-0499-7
DO - 10.1007/s10646-010-0499-7
M3 - Artículo
SN - 0963-9292
VL - 19
SP - 1157
EP - 1165
JO - Ecotoxicology
JF - Ecotoxicology
IS - 6
ER -