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Ahn, Chi‐Yong; Joung, Seung Hyun; Jeon, Jong Woon; Kim, Hee Sik; Yoon, Byung Dae; Oh, Hee‐Mock

doi:10.1023/a:1024508927361

Cited by 68 publications

(21 citation statements)

References 11 publications

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“…Most algicidal bacteria isolated from the environment are characterized as belonging to the genera Cytophaga, Saprospira, Pseudoalteromonas, and Alteromonas (55). Recently, other studies have confirmed that some species of Bacillus, such as B. subtilis and B. fusiformis, can inhibit the growth of M. aeruginosa (18,19). In the present study, we showed that 24 Bacillus strains exerted bactericidal activity against M. aeruginosa.…”

Section: Discussionsupporting

confidence: 67%

“…can suppress the growth of harmful algal bloom species (9,18,19). In a previous study, Ahn et al (18) revealed that the culture broth of Bacillus subtilis C1 containing 10 mg liter Ϫ1 surfactin completely inhibited the growth of M. aeruginosa, although these researchers did not further isolate the surfactin from the culture broth or construct a mutant to verify its inhibitory activity. As such, the active compound(s) and mechanisms of action remain to be identified.…”

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confidence: 99%

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Bacilysin from Bacillus amyloliquefaciens FZB42 Has Specific Bactericidal Activity against Harmful Algal Bloom Species

Chen

et al. 2014

Appl Environ Microbiol

105

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bHarmful algal blooms, caused by massive and exceptional overgrowth of microalgae and cyanobacteria, are a serious environmental problem worldwide. In the present study, we looked for Bacillus strains with sufficiently strong anticyanobacterial activity to be used as biocontrol agents. Among 24 strains, Bacillus amyloliquefaciens FZB42 showed the strongest bactericidal activity against Microcystis aeruginosa, with a kill rate of 98.78%. The synthesis of the anticyanobacterial substance did not depend on Sfp, an enzyme that catalyzes a necessary processing step in the nonribosomal synthesis of lipopeptides and polyketides, but was associated with the aro gene cluster that is involved in the synthesis of the sfp-independent antibiotic bacilysin. Disruption of bacB, the gene in the cluster responsible for synthesizing bacilysin, or supplementation with the antagonist N-acetylglucosamine abolished the inhibitory effect, but this was restored when bacilysin synthesis was complemented. Bacilysin caused apparent changes in the algal cell wall and cell organelle membranes, and this resulted in cell lysis. Meanwhile, there was downregulated expression of glmS, psbA1, mcyB, and ftsZ-genes involved in peptidoglycan synthesis, photosynthesis, microcystin synthesis, and cell division, respectively. In addition, bacilysin suppressed the growth of other harmful algal species. In summary, bacilysin produced by B. amyloliquefaciens FZB42 has anticyanobacterial activity and thus could be developed as a biocontrol agent to mitigate the effects of harmful algal blooms. Eutrophication of surface waters has many undesirable effects and can lead to major water quality issues in freshwater and coastal systems (1). This phenomenon results in blooms of harmful algal species in freshwater lakes and brackish waters throughout the world. Moreover, the excessive growth of harmful algae, such as microalgae and cyanobacteria, often increases the production of inherent toxins such as microcystins and nodularins that cause acute poisonings of fish, birds, and mammals, including humans (2). For example, dogs died after they were exposed to a cyanobacterial bloom of Microcystis aeruginosa in Lake Amstelmeer (The Netherlands), and the concentration of microcystin in this lake was up to 5.27 ϫ 10 3 g g Ϫ1 of dry weight (3). In recent years, harmful algal blooms of eutrophic water in China have occurred frequently, including in Lake Taihu and Lake Chaohu, and Microcystis is thought to be the dominant bloom genera (4).Many control techniques have been used to prevent and mitigate bloom problems, including yellow loess (5), clay (6), and chemical agents such as copper sulfate and hydrogen peroxide (7). However, each of the physical and chemical methods available to remediate eutrophic water is associated with certain disadvantages (8). Therefore, there is still a pressing need for environmentally friendly, cost-effective, and convenient bactericidal agents directed against cyanobacterial blooms in eutrophic lakes. Biological control agents such as bact...

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Section: Discussionsupporting

confidence: 67%

mentioning

confidence: 99%

Bacilysin from Bacillus amyloliquefaciens FZB42 Has Specific Bactericidal Activity against Harmful Algal Bloom Species

Chen

et al. 2014

Appl Environ Microbiol

105

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“…The joint toxicity effect of the PFOS and ZnO-NPs exposure could be explained in terms of interactions between the Zn 2+ and the surfactants. Based on the structural characteristics of the PFOS and ZnO-NPs, the potential reasons and mechanism hypotheses are as follows: the surfactants may damage the membranes by perturbing the lipid bilayers [50,51]. Therefore, nanoparticles penetrated through cell membranes easier and caused more serious damage to zebrafish.…”

Section: Discussionmentioning

confidence: 99%

Oxidative stress and apotosis to Zebrafish (Danio rerio) embryos exposed to perfluorooctane sulfonate (PFOS) and ZnO nanoparticles

Cai

Wang

et al. 2017

Int J Occup Med Environ Health

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Objectives: Perfluorooctane sulfonate (PFOS) and zinc oxide nanoparticles (ZnO-NPs) are frequently detected in the environment but few studies have assessed the joint toxicity of them. Oxidative stress and apoptosis to zebrafish (Danio rerio) embryos induced by the PFOS and ZnO-NPs were investigated in this study. Material and Methods: The embryos were exposed to the PFOS (0, 0.4, 0.8 and 1.6 mg/l), 25, 50 mg/l) and PFOS plus ZnO-NPs (0.4+12.5, 0.8+25 and 1.6+50 mg/l) mixture solutions until 96 h post-fertilization. Activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (Gpx) and malondialdehyde (MDA) content were measured in zebrafish embryos after exposure lasting for 96 h. At the same time, the genes expression related to reactive oxygen species (ROS) generation, oxidative damage and apoptosis were also measured. Results: A significant induction of the ROS accompanied by the increase in the activity of the Gpx and MDA contents were found in co-treatment groups. Furthermore, several apoptosis pathway related genes such as Bax, p53, caspase-3 and caspase-9 were significantly up-regulated in the PFOS plus ZnO-NPs exposure groups, while anti-apoptotic gene Bcl-2 was significantly down-regulated in the PFOS plus ZnO-NPs exposure groups. In addition, some oxidative stress-related genes such as Cat, GSH peroxidase 1 (Gpx1a) and superoxide dismutase 1 (Sod1) were also significantly down-regulated after the PFOS plus ZnO-NPs co-treatments. Conclusions: The results demonstrated that the PFOS plus ZnO-NPs co-exposure could cause more serious oxidative stress and apoptosis than the PFOS and ZnO-NPs exposure alone at the exposure concentrations above. The synergistic effects of the PFOS and ZnO-NPs may be the important mechanisms of their toxicity to zebrafish embryos. Int J Occup Med Environ Health 2017;30(2):213-229

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“…[ 6 ]. These algicidal bacteria inhibit the growth of harmful algae by attacking the cells either directly via cell-to-cell contact or indirectly via the release of algicdal substances [ 11 , 12 ], including proteases [ 13 ], peptides [ 14 ], bio-surfactants [ 15 , 16 ], amino acids [ 17 ] and antibiotics [ 18 ]. However, few purified compounds have been identified.…”

Section: Introductionmentioning

confidence: 99%

Toxic Effect of a Marine Bacterium on Aquatic Organisms and Its Algicidal Substances against Phaeocystis globosa

Yang

Chen

et al. 2015

PLoS ONE

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Harmful algal blooms have caused enormous damage to the marine ecosystem and the coastal economy in China. In this paper, a bacterial strain B1, which had strong algicidal activity against Phaeocystis globosa, was isolated from the coastal waters of Zhuhai in China. The strain B1 was identified as Bacillus sp. on the basis of 16S rDNA gene sequence and morphological characteristics. To evaluate the ecological safety of the algicidal substances produced by strain B1, their toxic effects on marine organisms were tested. Results showed that there were no adverse effects observed in the growth of Chlorella vulgaris, Chaetoceros muelleri, and Isochrystis galbana after exposure to the algicidal substances at a concentration of 1.0% (v/v) for 96 h. The 48h LC50 values for Brachionus plicatilis, Moina mongolica Daday and Paralichthys olivaceus were 5.7, 9.0 and 12.1% (v/v), respectively. Subsequently, the algicidal substances from strain B1 culture were isolated and purified by silica gel column, Sephadex G-15 column and high-performance liquid chromatography. Based on quadrupole time-of-flight mass spectrometry and PeakView Software, the purified substances were identified as prolyl-methionine and hypoxanthine. Algicidal mechanism indicated that prolyl-methionine and hypoxanthine inhibited the growth of P. globosa by disrupting the antioxidant systems. In the acute toxicity assessment using M. mongolica, 24h LC50 values of prolyl-methionine and hypoxanthine were 7.0 and 13.8 g/L, respectively. The active substances produced by strain B1 can be considered as ecologically and environmentally biological agents for controlling harmful algal blooms.

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Untitled

Cited by 68 publications

References 11 publications

Bacilysin from Bacillus amyloliquefaciens FZB42 Has Specific Bactericidal Activity against Harmful Algal Bloom Species

Bacilysin from Bacillus amyloliquefaciens FZB42 Has Specific Bactericidal Activity against Harmful Algal Bloom Species

Oxidative stress and apotosis to Zebrafish (Danio rerio) embryos exposed to perfluorooctane sulfonate (PFOS) and ZnO nanoparticles

Toxic Effect of a Marine Bacterium on Aquatic Organisms and Its Algicidal Substances against Phaeocystis globosa

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