The Bacillus Amyloliquefaciens Subsp Plantarum Strain d747 - Report Example

Table of Contents Background and nature of the substance 2 TAXONOMY OF THE SUBSTANCE 2 NATURE OF THE SUBSTANCE 3 Environmental fate and behavior of Bacillus amyloliquefaciens subsp. plantarum strain D747 4 Relevance to the Irish consumer 7 Risk Management strategy 10 References 11 TAXONOMY OF THE SUBSTANCE 2 Relevance to the Irish consumer 7 Risk Management strategy 10 References 11 The Bacillus amyloliquefaciens subsp. plantarum strain D74 Background and nature of the substance 2 TAXONOMY OF THE SUBSTANCE 2 NATURE OF THE SUBSTANCE 3 Relevance to the Irish consumer 7 Risk Management strategy 10 References 11 Background and nature of the substance The substance was isolated from the atmosphere in 2000 in Japan (EFSA, 18). It is a wild type with no genetic modification. The target organism is the Botrytis cinereas. The representative formulated product for the substance is CX 9030; which is a water dispersible particle formulation that contains 5x1013 CFU/Kg. the strain can grow at 37 degree Celsius and above. It is, however, not a pathogen for mammals. During the manufacturing process, any relevant secondary toxins or metabolites do not occur at the end use product. Moreover, the strain doesn’t contain the DNA material which encodes the Bacillus cereus toxins. The strain can, however, still produce some relevant secondary toxins or metabolites on its release to the environment. The Bacillus amyloliquefaciens subsp. plantarum strain D747 is a new active substance that was applied for approval by the Mitsui AgriScience International S.A. /B.V, In accordance with the Article 2 of the Commission Regulation (EU) NO 188/2011 of Germany. The EU recognized the completeness of the dossier by the Commission Decision of 2011/253/EU. The peer review on the substance was received by the EFSA on 14th of January 2013, and was then initiated on the 21st of January though dispatching it to the member states for comments and consultation. TAXONOMY OF THE SUBSTANCE The Bacillus amyloliquefaciens subsp. plantarum strain D747 is of the family Bacillaceae and genus Bacillus. It is characterized based on its physiological and morphological characteristics and through the molecular analysis of the RAPD, gyr B sequences, 16S rRNA and ribotyping analysis (EFSA, 18). Just like other members of the Bacillus subtilis group, Bacillus amyloliquefaciens subsp. plantarum strain D747 is ubiquitous in nature and a common rhisozphere and common soil bacterium. The identity of Bacillus species is a complicated and tough issue because of the availability of numerous sibling species of the genus that have not yet been distinctly known by the phenotype but have been proposed already. Most Bacillus species are used in the treatment of intestinal infections, endometritis, post-partum pyoinflamattory complications in cows and festering wounds. NATURE OF THE SUBSTANCE The Bacillus amyloliquefaciens subsp. Plantarum strain D747 controls fungal plant pathogens by combining differernt modes of action. They first B. amyloliquefaciens D747 competes effectively for nutrients and space with the plants pathogens, particularly where the nutrients are scarce on the leafs surface. Bacillus amyloliquefaciens subsp. Plantarum strain D747 then synthesizes nd releases lipopeptides that increase the fungus’ membrane permeability. B. amyloliquefaciens D747 then has the ability to synthesize different proteases that re able to degrade fungal infestation on the plants’ leaves (EFSA, 19). The host for Bacillus amyloliquefaciens subsp. Plantarum strain D747 is not a specific host. The content of contaminating micro-organisms of the strain is within acceptable levels. The Bacillus amyloliquefaciens subsp. plantarum strain D747 is mainly used as a fungicide on wine and table grapes. The assessment of the transfer of Bacillus amyloliquefaciens subsp. plantarum strain D747 from one organism to another has not yet been finalized by scientists. The Bacillus amyloliquefaciens subsp. plantarum strain D747 has no effect on mammals. The has been no sign of acute toxicity of the strain following intravenous, intratracheal oral administration of high doses of the strain to rats. It did not show the potential of invading the rat’s body or proliferating them; hence, the chance of risk infection was eliminated. For acute toxicity levels, there is no sign for acute toxicity after oral or percutaneous or inhalation administration for high doses to the rats. The product containing The Bacillus amyloliquefaciens subsp. plantarum strain D7471 is neither an eye nor skin irritant. Results from researches on the substance show no presence of metabolites or toxins at significant intensities in the product. Available evidence shows that the substance does not produce B. cereus-like the cytotoxic peptide amylosin and diarrheal enterotoxins. Since the Bacillus amyloliquefaciens subsp. plantarum strain D747 has no known effects on mammals, a quantitative risk assessment on residues is not needed. Environmental fate and behavior of Bacillus amyloliquefaciens subsp. plantarum strain D747 Information provided demonstrates that the Bacillus amyloliquefaciens subsp. plantarum strain D747 has no potential of interfering with analytical systems in the control of quality drinking water, as provided in the Council Directive 98/83/EC. There has been no specific information that supports the potential transfer of the substance from one organism to another. Research done on related species indicate a possibility of the organism being transferred. Studies done on Bacillus subtilis KB show that the ability to produce the metabolite iturin is not transferrable to other microbial species in soils at a greenhouse; there was no evidence of a horizontal transfer of genes under the conditions in the greenhouses. Fate and behaviour in the environment of the microorganism There has been zero indication to show the multiplication and persistence of Bacillus amyloliquefaciens subsp. plantarum strain D747 in the soil. However, studies done on related specie, Bacillus subtilis, showed a decline of vegetative cells of the species. The strain, Bacillus subtilis KB, in a greenhouse soils, took one hundred and fifty four days before the initial levels of the species declined by 10%. The strain, RB14, has vegetative cells that are more competitive; hence, they declined slowly and sporulated less than a derivation of the same strain, but which did not contain genes that coded for surfactant and iturin A. There is a data gap as to whether Bacillus amyloliquefaciens subsp. plantarum strain D747 can persist in soils that have higher concentrations that are higher than normal background levels. Bacillus amyloliquefaciens subsp. plantarum strain D747 is self-motile, but limited to the rhizosphere. Vegetative endospores and cells can move when carried around by water movements or arthropods. They can also move when they are carried by air, to a distance of roughly 200 meters. Bacillus amyloliquefaciens subsp. plantarum strain D747 can be found in two stages; as vegetative cells and endospores. With favorable temperature, nutrients conditions and moisture content, the spores can germinate and form vegetative cells that can grow, are metabolically active and proliferate. The differentiation of the endospores starts when the growth conditions are sub-optimal. Endospores are very durable and can remain viable for extremely long time periods. Both the endospore and vegetative cell constitute of colony forming units. A spore will need to germinate and become vegetative before the formation of a colony starts. Analysis of the health risk posed by this chemical The operator, resident, bystander exposure and work exposure estimates for the strain are not needed because of the lack of any significant infectivity, pathogenicity or toxicity levels in all available research studies on the strain. Bacillus amyloliquefaciens subsp. plantarum strain D747 shows antagonistic activity against a variety of bacterial or fungal plants pathogens. The substance is natutally available in the rhizophere and the plant surfaces and usually grows in those compartments after a field application. Outside the rhizosphere, Bacillus amyloliquefaciens subsp. plantarum strain D747 has poor colonization ability; hence, it is not a good competitor. Studies that have been done over the pathogenicity and toxicity of Bacillus amyloliquefaciens subsp. plantarum strain D747 on birds and mammals indicated that the substance has no visible effect on them. Even though the studies were of short durations and the administered doses were low, it can be safely concluded that the effect on terrestrial vertebrates is low. However, Bacillus amyloliquefaciens subsp. plantarum strain D747 has some effect on aquatic animals (with the experiment done on daphnids, fish and algae). The risks were low and had diverse adverse effects on the aquatic organisms. The strain also did not have any major effects on bees, earthworms and other soil microorganisms. Studies done on the effect of Bacillus amyloliquefaciens subsp. plantarum strain D747 on earthworms returned negative results; the strain did not have any toxicity, pathogenicity or effectiveness effect on the species. Tests on soli microbial activities also showed no influence on the activities, nitrate formation or carbon transformation. Bacillus amyloliquefaciens subsp. plantarum strain D747 can thus be concluded as not to have ant hazardous effects on the soil. The strain also did not have any dangerous effect on stems, corns, onions variants, spinach, leaves or pumpkin. It is therefore , not considered as nonhazardous to majority of agricultural produces. Bacillus mainly comprises of bacteria that colonize soil or plant surfaces. Some species of the genus are, however, pathogenic to insects or vertebrates. The B. subtilis group is quite uniform, and strains in this group include B. lincheniformis, B. mojavensis, B. pumilus, B. subtilis and the B. fusiformis. They are known to cause a rare case of food poisoning in the insects or vertebrates. The B. cereus group consists of a variety of human pathogens, like the B. cereus and the B. anthracis. B. thurigiensis is a widely used insect pathogen. It acts efficiently against Lepidopteranor the Dipteran pest. It has been widely used commercially as an insecticide for decades now. Strains belonging to the Bacillus subtilis group produce variety of metabolites with antifungal or antibiotic activities. Bacillus amyloliquefaciens subsp. plantarum strain D747 produces exo enzymes, including chitinase and amylase; hence, contribute to the decaying of organic matter. The metabolites iturin, serine proteinase subsitilisin and surfactin are not contained in a formulated product at the specific amounts required to contribute to activities, but are formed transiently after their application and during interactions with the pathogen. The extent of poisons from Bacillus amyloliquefaciens subsp. plantarum strain D747 in plants is not clear yet. Relevance to the Irish consumer Its significance of adding the part of fengycins created by strain GA1 is proven by the operational disease control shown by cure of fruits using CLP-enriched products and by detection of the fengycins in inhibitory quantities. Another newly established part for lipopeptides from valuable Bacillus segregates is the stimulation in the plants’ immune systems .Surfactins and, to a minor degree; fengycins can prompt a priming state in the host plant that allows an enhanced activation of the defense mechanisms upon insect or pathogen attack, creating an enhanced resistance to the attack encountered. Surfactants can also be considered as an original class consisting of microbial-associated molecular forms that can be precisely observed by plant cells as signals to stimulate their defense mechanisms. The microorganism limit the growth of a wide spectrum of pathogens. They produce proteolytic enzymes and biologically active metabolites, to supplement their probiotic activities. Probiotics are basic in the treatment of dysbacterioisis and infections and diseases that are associated with a deficient immunity. They subdue conditionally- pathogenic micro-flora and pathogenic related diseases. Their efficiency is complemented by the fact that they are absolutely safe to use, with zero chances of harm. The use of single-strains developing diverse mechanisms to lessen disease occurrence, is, thus, of main interest. Bacillus eradicates such as the strain GA1 that co-produces the three CLP families; hence, display a multi-faceted bio control activity. In strain GA1, the operon pointing to the synthesis of iturin A is B. subtilis. RB14 was found to be inserted at the unchanged position as the estimated bacylomycin D gene cluster from B. amyloliquefaciens FZB42. This suggests that an inter species level genes transfer could have taken place. These surfactants also play diverse roles in the survival and growth of some Bacillus strains in their normal habitats; increasing bio-availability of hydrophobic water insoluble substrates, heavy metal-binding, quorum sensing, bacterial pathogenesis, motility and biofilm formation. Moreover, Bacillus amyloliquefaciens subsp. plantarum strain D747 can be used as a biological control. The root colonization of the strain is determined by the biofilm formation and chemotaxis. Both the functions are regulated by the AbrB, the universal trasnscription regulator. Studies done by (Weng et al., 2012) of the Bacillus amyloliquefaciens SQR9 proved that it was a likely bio control agent for some crop diseases, especially on wheat and watermelon. Other studies have also underlined the additional traits that are very significant in the fitness of the Bacillus strains in the rhizosphere and for their efficacy as bio control agent. The ability of Bacillus amyloliquefaciens subsp. plantarum strain D747 to resourcefully colonize the plant’s surfaces and roots is a requirement for phyto protection. The process depends on the surface motility plus an efficient biofilm formation; the Bacillus cell population that evolves and behave as coordinated and structured micro colonies sticking to the root and onto the soil particles surfaces. By adjusting the cell surface features, iturin and surfactin were described to positively impact cell spreading and swarming in biofilm formation; and thus, they may universally support plant root colonization. Moreover, fengycins and iturins display some strong anti-fungal activities and inhibit the growth and development of an extensive range of plants’ pathogens. Surfactins themselves are not fungi-toxic, but keep some synergistic influence on the anti-fungal activities of iturin A. In bio control, the participation of CLPs in the direct antagonism of phyto pathogens is clear and was verified by testing the uncontaminated compounds in some plants and correlating the bio control activities and using of non-producing derivatives. Apart from lipopepides, a cyclic trimeric lactone of the 2,3-dihydroxybenzoyl-Gly-Thr monomer unit. Siderophores are high affinity ferric iron chelators that increase the microbial attainment of the element in the environment where its bio-availability is really low, like in soils. Hence, the occurrence of siderophore producing micro-organisms in the rhizosphere backs the plants health by complexing the element iron and making it a lesser amount of available to phyto pathogens that are usually unable to produce comparable amounts of iron. Risk Management strategy Bacillus amyloliquefaciens subsp. plantarum strain D747 is has no known risk factors for the majority of animals. This nearly makes the substance harmless; hence, there is no compelling need for its management. However, in plants, the substance has several effects on the parts; thus a need to manage it. Bacillus amyloliquefaciens subsp. plantarum strain D747 is susceptible to several antibiotics. These antibiotics include Penicillins, Cephalosporins, Fluorochinolons, amino glycosides and Glycopeptides. Their sensitivity to the antibiotics can be exploited and used to curb its effects when not needed. Moreover, Bacillus amyloliquefaciens subsp. plantarum strain D747 can be used as a biological control. Thr root colonization of the strain is determined by the biofilm formation and chemotaxis. Both the functions are regulated by the AbrB, the universal trasnscription regulator. Studies done by (Weng et al., 2012) of the Bacillus amyloliquefaciens SQR9 proved that it was a likely bio control agent for some diseases References EFSA (2014.) Conclusion on the peer review of the pesticide risk assessment of the active substance Bacillus amyloliquefaciens subsp. plantarum strain D7471. (2014). European Food Safety Authority, 12(4), pp.1-29. Weng, J., Wang, Y., Li, J., Shen, Q. and Zhang, R. (2012). Enhanced root colonization and biocontrol activity of Bacillus amyloliquefaciens SQR9 by abrB gene disruption. Applied Microbiology and Biotechnology, 97(19), pp.8823-8830. Read More