scholarly journals Genomic insight for Algicidal activity in Rhizobium sp. (AQ_MP)

2021 ◽  
Author(s):  
Mili Pal ◽  
Asifa Qureshi ◽  
Hemant Purohit
Keyword(s):  
Microcystis Aeruginosa ◽  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Nutrient Release ◽  
Glycoside Hydrolases ◽  
Polysaccharide Lyases ◽  
Responsible Gene ◽  
Wide Range ◽  
Biological Detoxification ◽  
Rhizobium Sp

Abstract Occurrence of Harmful Algal Blooms (HABs) creates a threat to aquatic ecosystem affecting the existing flora and fauna. Hence, the mitigation of HABs through an eco-friendly approach remains a challenge for environmentalists. The present study provides the genomic insights of Rhizobium sp. (AQ_MP), an environmental isolate that showed the capability of degrading Microcystis aeruginosa (Cyanobacteria) at laboratory scale. Genome sequence analysis of Rhizobium sp. (AQ_MP) was performed to determine the algal lysis properties and toxin degradative pathway. It is envisaged that Rhizobium sp. (AQ_MP) secreted CAZymes like Glycosyltransferases (GT), Glycoside Hydrolases (GH), polysaccharide lyases (PL), which allowed algal polysaccharide degradation (lysis) and enabled nutrient release for the subsequent growth of Rhizobium sp. (AQ_MP) Genome analysis also showed the presence of the glutathione metabolic pathway, which is the biological detoxification pathway responsible for microcystin degradation. The conserved region mlrC, a microcystin toxin degrading responsible gene, was also annotated in Rhizobium sp. (AQ_MP). This study confirmed that Rhizobium sp. (AQ_MP) harbours a wide range of crucial enzymes released for lysis of Microcystis aeruginosa (M. aeruginosa) cells and also for degradation of microcystin toxin. This study thus find promiscuity for scaling the lab based analysis to field level in future.

Using Fundamental Optical Property Sensors for Characterization of Biogeochemical Materials and Processes in Marine Waters

2008 ◽  
Vol 42 (1) ◽  
pp. 75-83 ◽  
Author(s):  
Casey Moore
Keyword(s):  
Optical Properties ◽  
Optical Property ◽  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Natural Waters ◽  
Harmful Algal Bloom ◽  
Light Level ◽  
Ecosystem Dynamics ◽  
Wide Range ◽  
Biogeochemical Parameters

Over the past ten years, efforts to characterize the optical properties of Earth's natural waters have largely merged with the need to better understand underlying biological and chemical processes. Fundamental optical properties such as light level, absorption, scattering and fluorescence are now being utilized with increasing effectiveness to specify particulate and dissolved in-water components in a wide range of applications, including detection of harmful algal blooms, studying ecosystem dynamics, monitoring the effect of industrial and agricultural pollutants, and understanding carbon sequestration processes in the oceans. A diverse offering of commercial optical sensing products capable for research, routine measurements, and in some cases, operational monitoring are now available. These technologies have provided the scientific community with a set of tools for developing, testing, and placing into practice analytical and semi-analytical methods to infer specific biogeochemical parameters and processes. As a result, new, more specialized sensors are now emerging. New sensors couple basic optical property measurements with processing algorithms to provide specific indicators for Harmful Algal Bloom (HAB) identification, carbon products, nutrients, and particle size distributions. The basic measurement methods are described and examples of devices incorporating them are provided to illustrate their use in modern oceanographic research and monitoring.

scholarly journals Associations between chlorophyll a and various microcystin-LR health advisory concentrations

F1000Research ◽  
2016 ◽  
Vol 5 ◽  
pp. 151 ◽  
Author(s):  
Jeffrey W. Hollister ◽  
Betty J. Kreakie
Keyword(s):  
Drinking Water ◽  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Field Measurements ◽  
World Health ◽  
Health Advisory ◽  
Adverse Health Effects ◽  
Wide Range ◽  
Recreational Use

Cyanobacteria harmful algal blooms (cHABs) are associated with a wide range of adverse health effects that stem mostly from the presence of cyanotoxins. To help protect against these impacts, several health advisory levels have been set for some toxins. In particular, one of the more common toxins, microcystin-LR, has several advisory levels set for drinking water and recreational use. However, compared to other water quality measures, field measurements of microcystin-LR are not commonly available due to cost and advanced understanding required to interpret results. Addressing these issues will take time and resources. Thus, there is utility in finding indicators of microcystin-LR that are already widely available, can be estimated quickly and in situ, and used as a first defense against high concentrations of microcystin-LR. Chlorophyll a is commonly measured, can be estimated in situ, and has been shown to be positively associated with microcystin-LR. In this paper, we use this association to provide estimates of chlorophyll a concentrations that are indicative of a higher probability of exceeding select health advisory concentrations for microcystin-LR. Using the 2007 National Lakes Assessment and a conditional probability approach, we identify chlorophyll a concentrations that are more likely than not to be associated with an exceedance of a microcystin-LR health advisory level. We look at the recent US EPA health advisories for drinking water as well as the World Health Organization levels for drinking water and recreational use and identify a range of chlorophyll a thresholds. A 50% chance of exceeding one of the microcystin-LR advisory concentrations of 0.3, 1, 1.6, and 2 g/L is associated with chlorophyll a concentration thresholds of 23.4, 67.0, 83.5, and 105.8, respectively. When managing for these various microcystin-LR levels, exceeding these reported chlorophyll a concentrations should be a trigger for further testing and possible management action.

scholarly journals Transcriptional Analysis of Microcystis aeruginosa Co-Cultured with Algicidal Bacteria Brevibacillus laterosporus

2021 ◽  
Vol 18 (16) ◽  
pp. 8615
Author(s):  
Yulei Zhang ◽  
Dong Chen ◽  
Ning Zhang ◽  
Feng Li ◽  
Xiaoxia Luo ◽  
...  
Keyword(s):  
Microcystis Aeruginosa ◽  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Control Method ◽  
Acid Synthesis ◽  
Transcriptional Analysis ◽  
Economic Losses ◽  
Algicidal Bacteria ◽  
Brevibacillus Laterosporus ◽  
Expression Of Genes

Harmful algal blooms caused huge ecological damage and economic losses around the world. Controlling algal blooms by algicidal bacteria is expected to be an effective biological control method. The current study investigated the molecular mechanism of harmful cyanobacteria disrupted by algicidal bacteria. Microcystis aeruginosa was co-cultured with Brevibacillus laterosporus Bl-zj, and RNA-seq based transcriptomic analysis was performed compared to M. aeruginosa, which was cultivated separately. A total of 1706 differentially expressed genes were identified, which were mainly involved in carbohydrate metabolism, energy metabolism and amino acid metabolism. In the co-cultured group, the expression of genes mainly enriched in photosynthesis and oxidative phosphorylation were significantly inhibited. However, the expression of the genes related to fatty acid synthesis increased. In addition, the expression of the antioxidant enzymes, such as 2-Cys peroxiredoxin, was increased. These results suggested that B. laterosporus could block the electron transport by attacking the PSI system and complex I of M. aeruginosa, affecting the energy acquisition and causing oxidative damage. This further led to the lipid peroxidation of the microalgal cell membrane, resulting in algal death. The transcriptional analysis of algicidal bacteria in the interaction process can be combined to explain the algicidal mechanism in the future.

scholarly journals Associations between chlorophyll a and various microcystin health advisory concentrations

F1000Research ◽  
2016 ◽  
Vol 5 ◽  
pp. 151 ◽  
Author(s):  
Jeffrey W. Hollister ◽  
Betty J. Kreakie
Keyword(s):  
Drinking Water ◽  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Field Measurements ◽  
World Health ◽  
Health Advisory ◽  
Adverse Health Effects ◽  
Wide Range ◽  
Recreational Use

Cyanobacteria harmful algal blooms (cHABs) are associated with a wide range of adverse health effects that stem mostly from the presence of cyanotoxins. To help protect against these impacts, several health advisory levels have been set for some toxins. In particular, one of the more common toxins, microcystin, has several advisory levels set for drinking water and recreational use. However, compared to other water quality measures, field measurements of microcystin are not commonly available due to cost and advanced understanding required to interpret results. Addressing these issues will take time and resources. Thus, there is utility in finding indicators of microcystin that are already widely available, can be estimated quickly and in situ, and used as a first defense against high levels of microcystin. Chlorophyll a is commonly measured, can be estimated in situ, and has been shown to be positively associated with microcystin. In this paper, we use this association to provide estimates of chlorophyll a concentrations that are indicative of a higher probability of exceeding select health advisory concentrations for microcystin. Using the 2007 National Lakes Assessment and a conditional probability approach, we identify chlorophyll a concentrations that are more likely than not to be associated with an exceedance of a microcystin health advisory level. We look at the recent US EPA health advisories for drinking water as well as the World Health Organization levels for drinking water and recreational use and identify a range of chlorophyll a thresholds. A 50% chance of exceeding one of the specific advisory microcystin concentrations of 0.3, 1, 1.6, and 2 μg/L is associated with chlorophyll a concentration thresholds of 23, 68, 84, and 104 μg/L, respectively. When managing for these various microcystin levels, exceeding these reported chlorophyll a concentrations should be a trigger for further testing and possible management action.

Quantifying the efficacy of diquat dibromide in controlling Microcystis aeruginosa and Aphanizomenon flos-aquae in comparison to copper sulfate and potassium permanganate

2019 ◽  
Vol 5 (1) ◽  
pp. 140-151 ◽  
Author(s):  
Sara Dia ◽  
Ibrahim Alameddine ◽  
Mutasem El-Fadel
Keyword(s):  
Potassium Permanganate ◽  
Microcystis Aeruginosa ◽  
Copper Sulfate ◽  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Freshwater Systems ◽  
Cyanobacterial Harmful Algal Blooms

Cyanobacterial harmful algal blooms (HABs) are an emerging problem worldwide, affecting many important freshwater systems.

scholarly journals Abundant Allelochemicals and the Inhibitory Mechanism of the Phenolic Acids in Water Dropwort for the Control of Microcystis aeruginosa Blooms

Plants ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 2653
Author(s):  
Jixiang Liu ◽  
Yajun Chang ◽  
Linhe Sun ◽  
Fengfeng Du ◽  
Jian Cui ◽  
...  
Keyword(s):  
Microcystis Aeruginosa ◽  
Phenolic Acids ◽  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Inhibitory Effect ◽  
Simultaneous Action ◽  
Inhibitory Effects ◽  
Chl A ◽  
Ferulic Acids ◽  
Water Dropwort

In recent years, with the frequent global occurrence of harmful algal blooms, the use of plant allelopathy to control algal blooms has attracted special and wide attention. This study validates the possibility of turning water dropwort into a biological resource to inhibit the growth of harmful Microcystis aeruginosa blooms via allelopathy. The results revealed that there were 33 types of allelopathic compounds in the water dropwort culture water, of which 15 were phenolic acids. Regarding water dropwort itself, 18 phenolic acids were discovered in all the organs of water dropwort via a targeted metabolomics analysis; they were found to be mainly synthesized in the leaves and then transported to the roots and then ultimately released into culture water where they inhibited M. aeruginosa growth. Next, three types of phenolic acids synthesized in water dropwort, i.e., benzoic, salicylic, and ferulic acids, were selected to clarify their inhibitory effects on the growth of M. aeruginosa and their mechanism(s) of action. It was found that the inhibitory effect of phenolic acids on the growth of M. aeruginosa increased with the increase of the exposure concentration, although the algae cells were more sensitive to benzoic acid than to salicylic and ferulic acids. Further study indicated that the inhibitory effects of the three phenolic acids on the growth of M. aeruginosa were largely due to the simultaneous action of reducing the number of cells, damaging the integrity of the cell membrane, inhibiting chlorophyll a (Chl-a) synthesis, decreasing the values of F0 and Fv/Fm, and increasing the activity of the antioxidant enzymes (SOD, POD, and CAT) of M. aeruginosa. Thus, the results of this study indicate that both culture water including the rich allelochemicals in water dropwort and biological algae inhibitors made from water dropwort could be used to control the growth of noxious algae in the future.

scholarly journals Nutrient Loading and Viral Memory Drive Accumulation of Restriction Modification Systems in Bloom-Forming Cyanobacteria

mBio ◽  
2021 ◽  
Author(s):  
Spiridon E. Papoulis ◽  
Steven W. Wilhelm ◽  
David Talmy ◽  
Erik R. Zinser
Keyword(s):  
Water Quality ◽  
Microcystis Aeruginosa ◽  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Nutrient Loading ◽  
Major Contributor ◽  
Content Type ◽  
Global Threat ◽  
Restriction Modification ◽  
Restriction Modification Systems

Harmful algal blooms (HABs), caused by cyanobacteria like Microcystis aeruginosa , are a global threat to water quality and use across the planet. Researchers have agreed that nutrient loading is a major contributor to HAB persistence.

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