RRC ID 47181
Author Srivastava A, Ko SR, Ahn CY, Oh HM, Ravi AK, Asthana RK.
Title Microcystin Biosynthesis and mcyA Expression in Geographically Distinct Microcystis Strains under Different Nitrogen, Phosphorus, and Boron Regimes.
Journal Biomed Res Int
Abstract Roles of nutrients and other environmental variables in development of cyanobacterial bloom and its toxicity are complex and not well understood. We have monitored the photoautotrophic growth, total microcystin concentration, and microcystins synthetase gene (mcyA) expression in lab-grown strains of Microcystis NIES 843 (reference strain), KW (Wangsong Reservoir, South Korea), and Durgakund (Varanasi, India) under different nutrient regimes (nitrogen, phosphorus, and boron). Higher level of nitrogen and boron resulted in increased growth (avg. 5 and 6.5 Chl a mg/L, resp.), total microcystin concentrations (avg. 1.185 and 7.153 mg/L, resp.), and mcyA transcript but its expression was not directly correlated with total microcystin concentrations in the target strains. Interestingly, Durgakund strain had much lower microcystin content and lacked microcystin-YR variant over NIES 843 and KW. It is inferred that microcystin concentration and its variants are strain specific. We have also examined the heterotrophic bacteria associated with cyanobacterial bloom in Durgakund Pond and Wangsong Reservoir which were found to be enriched in Alpha-, Beta-, and Gammaproteobacteria and that could influence the bloom dynamics.
Volume 2016
Pages 5985987
Published 2016
DOI 10.1155/2016/5985987
PMID 27803926
PMC PMC5075592
MeSH Bacterial Proteins / metabolism* Boron / metabolism* Gene Expression Regulation, Bacterial / physiology Geography Microcystins / biosynthesis* Microcystis / classification Microcystis / metabolism* Nitrogen / metabolism* Phosphorus / metabolism* Species Specificity
IF 2.197
Resource
Algae NIES-843