Figure Diferencias en la comunidad microbiana intestinal . of a gram- negative bacterium that produces endotoxins. Toxinas: Exotoxinas y endotoxinas . No hubo diferencias significativas entre los tratamientos de exo- toxinas, endotoxinas y toxinas labiles al ca- lor y el control (Fig. 5). La Fig. 6 muestra el View. Algunos de estos factores de virulencia, como fosfolipasas, enterotoxinas, b- exotoxinas, Las diferencias aminoacídicas que presentan se traducen comúnmente en . que codifican otros factores de virulencia distintos de las d- endotoxinas.
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New strain of Bacillus intended to combat plant diseases and rootworm corn. The present invention is in the field of biopesticides.
More specifically, this invention diferejcias to the discovery that a novel strain of Bacillus subtilis, AQ, can inhibit a broad range of fungal and bacterial plant diseases and also have activity against rootworm corn. The invention also relates to fungicidal, bactericidaland insecticidal compositions comprising this novel Bacillus strain and the antibiotics and exotoxinaw produced by this strain, either alone or in combination with other chemical and biological pesticides. For a number of years, it has been known that various microorganisms exhibit biological activity to be useful in controlling plant diseases.
Although progress has been made in the field of identifying and developing biological pesticides for controlling various plant diseases of agronomic and horticultural importance, most of the pesticides in use are still synthetic compounds.
Many of these chemical fungicides are classified as carcinogens by the EPA and are toxic to wildlife and other species that are not their goal. Every year million dollars of chemical pesticides are used to control infestations by rootworm corn.
Many of these chemical pesticides are toxic to humans, to wildlife and other species that are not their goal. In difeerncias, some have been found in groundwater. Biological control offers an alternative to synthetic chemical fungicides. Biopesticides living organisms and the naturally produced compounds produced by these organisms can be safer, more biodegradable, and less expensive to develop. Los programas de rastreo han identificado ciertas cepas endotoxinaz Bacillus spp Bacillus spp.
Screening programs have identified certain Bacillus spp Bacillus spp. See, eg, Stabb et al Applied Environ Microbiol Zwittermicin-A is a water soluble molecule, acid stable see He et al linear aminopolyol. When the seed was coated with B. Similarly, it has been found that the application of spore-based formulations of certain B.
See Osburne et alPhytopathol Soc Am 79 Application methods biopesticides are well known in the art and include, for example, wettable powders, dry flowables, microencapsulation of effective agents and liquid or solid formulations of antibiotic fractions from suitable cultures. See, eg, US Patent No. The whole broth filtrates and free cell were active against Botrytis and Alternaria in in vitro tests and were active against Botrytis in in vivo tests on Astilbe small plants.
RossallPatente EE. Singh and Deverall Trans. The same authors, Islam and Nandi Journal of Plant Diseases and Protection 92 3, also describe the in vitro antagonism against Drechslera oryzae B.
Discuten tres componentes en el filtrado de cultivo. Discuss three components in the culture filtrate. The most active antibiotic was highly soluble in water and methanol with a UV peak at nm and a shoulder at nm, which proved to be a polyoxin-like lipopeptide.
Cook Proceedings Beltwide Cotton Production. Mechanization Research Conference, Cotton Council, Memphis, pp discloses the use of a suspension of Bacillus megaterium to reduce the number of cotton plants killed by Phymatotrichum omnivorum, a u of root rot cotton.
Antibiotic production of B. Are known to produce bacilli Korzybski et al. Los investigadores de la Universidad de Wisconsin y Cornell han identificado un nuevo compuesto fungicida, la zwittermicina A, producido por Bacillus sp. Researchers at the University of Wisconsin and Difeerncias have identified a novel fungicidal compound, zwittermicin A, produced by Bacillus sp.
He et al, Tetra Lett 35 One second fungicidal metabolite produced by the same strain as the known amino acid was recently identified kanosamine Milner et al Appl Environ Microb Another group of previously described Bacillus metabolites are the cyclic lipopeptides of the iturin class, some of which are potent fungicidal agents.
There are several groups of iturins that differ in order and content of the amino acid sequence.
Curso: Microbiología – Area Básica
These are shown in Table 1 below. In general, it produces a series of related differences in the length and branching of the aliphatic amino acid residue molecules.
It described that the mode of action of these cyclic lipopeptides is due to interaction with fungal membranes creating transmembrane channels that permit release of vital ions Latoud et al Biochem Biophys Acta La iturina-C es inactiva frente a hongos, incluyendo Penicillium chrysogenum Peypoux y col.
Iturin-C is inactive against fungi including Penicillium chrysogenum Peypoux et al Tetrahedron. Plant Growth Regulation Soc. Also they state that the “amounts of iturins obtained from natural production are inadequate to be commercially viable” based on their work with a number of Bacillus strains producing iturin. Other groups of cyclic lipopeptides isolated from B.
These compounds are a family of acylated decapeptides, the structures of which are shown in Figure 1 Nishikiori et alJ. Yamada also reported an observed synergistic effect between iturin A and the plipastatins, both produced by the same B.
There is a report of synergy between the closely related surfactins, that are themselves inactive, and the iturins produced by the same B. It has published nucleotide sequence for the gene that co-regulates biosynthesis iturin A and surfactin Huang et al J Ferment Bioeng 76 El trabajo de campo sobre cepas productoras de iturinas se ha concentrado en el tratamiento de suelos para el control de Rhizoctonia Asaka y ShodaAppl.
Another cyclic lipopeptide compound produced by B. El nuevo microorganismo AQ descubierto por los inventores, que previamente se pensaba que era una cepa de Bacillus megaterium y se ha identificado ahora como una cepa de Bacillus subtilisproduce iturinas A, plipastatinas y surfactinas. The novel microorganism AQ discovered by the inventors, previously thought to be a strain of Bacillus megaterium and now identified as a strain of Bacillus subtilis, produces iturins A, plipastatins and surfactin.
Production of this combination of lipopeptides by a microorganism has not been previously described. Moreover, the inventors have discovered that AQ they also produces a newly described group of “agrastatins” compounds called. The combination of the three known above compounds with novel agrastatins is also novel. A commonly used biopesticide is the gram positive bacterium Bacillus thuringiensis. Se sabe que las cepas pesticidas de B. Pesticides are known B.
Microbiología – Area Básica
Las endotoxinas proteicas producidas por B. Proteinaceous endotoxins produced by B. Johnson, TJ et alJ. Se ha visto que las endotoxinas de B. It has been found that endotoxins ezotoxinas B. Un metabolito termoestable de B. Burgjeron y BiacheEntomophaga Burgjeron and BiacheEntomophaga Furthermore, the known beta-exotoxin B.
La sigma-exotoxina tiene una estructura similar a la beta-exotoxina y es activa contra el escarabajo de la patata de Colorado Argauer y col. The sigma-exotoxin is similar to beta-exotoxin structure and is active against Colorado potato beetle Colorado Argauer et alJ. Gamma-exotoxins are the various proteolytic enzymes, chitinases and proteases. The toxic effects of gamma exotoxins are only expressed-in combination with beta-exotoxin and delta-endotoxin. There are no documented strains of Bacillus with fungicidal activity over time and rootworm corn.
No existen metabolitos conocidos producidos por Bacillus subtilis que tengan un peso molecular menor de There are produced by Bacillus subtilis known metabolites having a molecular weight less than 10, and are extractable in a non – polar solvent.
A new antibiotic – producing strain and production of metabolites of Bacillus subtilis, previously identified as Bacillus megaterium which exhibits broad fungicidal and bactericidal activity and also exhibits activity on rootworm corn is presented. A new metabolite of new B.
A method of treating or protecting plants from fungal and bacterial infections comprising the step of applying an effective amount of the antibiotic – producing Bacillus subtilis is also presented. The antibiotic – producing Bacillus subtilis can be presented as a suspension in a whole broth culture or supernatant containing antibiotic obtained from a whole broth culture of the antibiotic – producing strain of Bacillus.
A method of treating or protecting plant roots against infestations by rootworm consisting of corn in the step of applying an effective amount of the novel metabolite – producing Bacillus subtilis is also presented.
The new metabolite – producing Bacillus subtilis can be presented as a suspension in a whole broth culture or as a metabolite – containing supernatant. Figure 1 shows the structure of the plipastatin antibiotics. The present invention provides a novel strain, AQ, of Bacillus subtilis, previously identified as a Bacillus megaterium, or mutants thereof with the broad antifungal and antibacterial activity and the novel combination of antifungal and anti-corn rootworm activity maize.
The invention also includes methods of preventing and treating fungal and bacterial diseases in plants using such bacterial or supernatants strains containing antibiotics or obtained pure antibiotics such bacterial strains, wherein said antibiotics are contained in a composition as defined in the claims.
The invention also includes methods of treating plant roots or soil to control larval rootworm corn with a bacterial suspension of AQ or a metabolite-containing supernatant of a culture of AQ The invention further includes novel compounds, agrastatins, produced by the novel microorganism.
Also included is a novel combination comprising an A-type iturin, a plipastatin, a surfactin and an agrastatin. As used herein, “biological control” is defined as control of a pathogen or insect by the use of a second organism. Known mechanisms of biological control include enteric bacteria that control root rot competing fungi for space on the surface of the root.
They were used bacterial infections, such as antibiotics, to control pathogens. La toxina puede ser aislada y aplicada directamente a la planta, o se puede administrar la especie bacteriana para que produzca la toxina in situ. The toxin can be isolated and applied directly to the plant or the bacterial species may be administered so that it produces the toxin in situ. The term “fungus” or “fungi” includes a wide variety of nucleated spore-bearing organisms that are devoid of chlorophyll.
Examples of fungi, yeasts, molds, mildews, rusts, and mushrooms include. The term “bacteria” includes any prokaryotic organism that does not have a distinct nucleus. Antibiotics may be produced by a microorganism or by a synthetic process or semisynthetic process.
The term “culture” refers to the propagation of organisms on or in media of various kinds. Una “cantidad efectiva” es una cantidad suficiente para producir resultados beneficiosos o deseados.