Isolation and endotoxin activities of lipopolysaccharides from cyanobacterial cultures and complex water blooms and comparison with the effects of heterotrophic bacteria and green alga

Abstract

Massive cyanobacterial water blooms are serious environmental and health problems worldwide. While some cyanobacterial toxins such as peptide microcystins have been investigated extensively, other toxic components of cyanobacteria (e.g. lipopolysaccharides, LPS) are poorly understood. The present study characterized endotoxin activities of LPS isolated from (i) laboratory cyanobacterial cultures, (ii) cyanobacterial water bloom samples dominated by Microcystis sp., Planktothrix sp., Aphanizomenon sp. and Anabaena sp., (iii) heterotrophic Gram-negative bacteria Escherichia coli, Kluyvera intermedia, Pseudomonas putida and Pseudomonas fluorescens and (iv) green alga Pseudokirchneriella subcapitata. Toxicity results derived with Limulus amebocyte lysate assay (LAL-test) showed that endotoxin activities of LPS from both cyanobacteria and heterotrophic bacteria were comparable and the values were within a similar range (1 x 10(3)-1 x 10(6) Endotoxin Units, EU, per mg of isolated LPS). The highest activities among the cyanobacterial samples were observed in the Aphanizomenon sp. dominated water bloom. The results also suggest generally higher endotoxin activities in complex natural samples than in laboratory cyanobacterial cultures. Further, experiments with the eukaryotic green alga P. subcapitata demonstrated a need for careful purification of the LPS extracts prior to testing with the LAL assay as several contaminants may overestimate endotoxin activities. This study shows relatively high pyrogenicity of LPS from various cyanobacteria. Further research should focus on detailed toxicological and ecotoxicological characterization of LPS in massive cyanobacterial water blooms.

Effects of microcystins-containing cyanobacteria from a temperate ecosystem on human lymphocytes culture and their potential for adverse human health effects

“…However the recent publication of biological activity of other ''non-toxic'' cyanobacterial cyclic peptides such as anabenopeptins or depsipeptides, which can interfere with the cytoskeleton of mammalian cells and act as cytostatic compounds, supports a wide range of bioactive compounds in cyanobacteria than the characterized toxins (Bubik et al, 2008;Sedmak et al, 2008). Moreover, several publications described the modulatory effects of cyanobacterial lipopolysaccharides (LPS) on the metabolism and toxicity of other compounds including microcystins (Best et al, 2003;Lindsay et al, 2006;Bernardová et al, 2008). Additionally, cyanobacteria can cumulate different chemicals: inorganic, organo-metallic and organic (Baptista and Vasconcelos, 2006).…”

Surface charge and zeta-potential of metabolically active and dead cyanobacteria

“…filamentous cyanobacteria contain S-layers as part of their surface structure and grow in solitary trichomes without sheaths, heterocytes, and akinetes [23]. This cyanobacteria species has been associated with freshwater reservoir eutrophication [24,25]. Cyanobacteria summer blooms develop into serious environmental and health problems [24,25].…”

“…This cyanobacteria species has been associated with freshwater reservoir eutrophication [24,25]. Cyanobacteria summer blooms develop into serious environmental and health problems [24,25]. Planktothrix sp.…”

LOCAD-PTS: Operation of a new system for microbial monitoring aboard the International Space Station (ISS)

“…The LAL assay is now used routinely to monitor endotoxin, as an important entity by itself and as a proxy for Gram-negative bacteria, in a wide range of products and applications. These include: dairy products 23 , eye surgery 24 , heart surgery 25 , dental surgery 26 , diagnosis of gram-negative peritonitis 27 , biofilms in dialysis systems 28 , organs for transplantation 29 , microbial contamination of metal-working fluids 30 , air monitoring in factories 31 , research of cyanobacterial blooms 32 , in plasmid-DNA based gene therapy to verify that gene vectors are endotoxinfree 33,34 . While the LAL assay can be coupled to a turbidimetric reaction, this is time-consuming and laborintensive.…”