Mosquitocidal xenorhabdus, lipopeptide and methods

Abstract

Provided is a bacterial strain which produces a family of mosquitocidal toxins, Xenorhabdus MT, on deposit with the American Type Culture Collection, PTA-6826, insecticidal compositions comprising the mosquitocidal toxin(s) produced by Xenorhabdus MT, a mosquitocidal toxin preparation prepared from spent culture medium, whole culture or cells or a mixture thereof, of Xenorhabdus MT and method of insect control, especially mosquito control. Also provided are microbial compounds (same as mosquitocidal toxins) compositions comprising them and use in formulating therapeutic and other antimicrobial compositions, and methods of use for inhibiting microbial growth and for treating infection.

We claim: 
     
         1 . A method of controlling an insect comprising the step of applying to an environment of the insect an effective amount of a lipopeptide toxin having functional activity against an insect, wherein said lipopeptide toxin is produced by a pure bacterial culture of  Xenorhabdus  MT deposited with the ATCC as PTA-6826. 
     
     
         2 . The method of  claim 1 , wherein the insect is a Dipteran insect. 
     
     
         3 . The method of  claim 2  wherein the insect is a member of the Culicidae. 
     
     
         4 . The method of  claim 3  wherein the insect is a mosquito of the genus  Culex, Aedes  or  Anopheles.    
     
     
         5 . The method of  claim 1  wherein said lipotoxin toxin comprises histidine, diaminobutyric acid, asparagine and/or aspartate, serine and glycine, and at least one saturated straight chain fatty acid, a 2-oxo fatty acid, 3-oxo fatty acid or a 4-oxo fatty acid, wherein the fatty acid has a chain length of from C8 to C20 or of from C10 to C18. 
     
     
         6 . The method of  claim 1 , further comprising an insecticidal toxin having functional activity against an insect in a mixture of one or more toxins produced from a purified culture of  Xenorhabdus  MT, deposited with American Type Culture Collection Accession No. PTA-6826. 
     
     
         7 . The method of  claim 1 , wherein the lipopeptide is contained within a composition comprising (i) dried whole culture of the  Xenorhabdus , (ii) concentrated whole culture of the  Xenorhabdus , (iii) dried cell free medium from a culture of the  Xenorhabdus , (iv) concentrated whole cell free medium from a culture of the  Xenorhabdus  or (v) purified lipopeptide toxin. 
     
     
         8 . The method of  claim 7 , wherein the composition comprises an additional insecticidal component. 
     
     
         9 . The method of  claim 8 , wherein the additional insecticidal component is a chemical or a biological insecticide. 
     
     
         10 . The method of  claim 9 , wherein the biological insecticide is a bacterial toxin, spinosyn, a plant insecticidal toxin or an insect virus. 
     
     
         11 . The method of  claim 9 , wherein the biological insecticide is a bacterial toxin produced by a  Bacillus thuringiensis  or a  Bacillus thuringiensis israeliensis  strain. 
     
     
         12 . The method of  claim 11 , wherein the  Xenorhabdus  protein is native to  Xenorhabdus  MT, American Type Culture Collection Accession No. PTA 6826. 
     
     
         13 . A method of controlling a microorganism, said method comprising the step of administering an effective amount of a mosquitocidal and/or antimicrobial composition comprising a lipopeptide toxin produced by the  Xenorhabdus  MT deposited with the American Type Culture Collection as PTA-6826, said toxin comprising histidine, diaminobutyric acid, asparagine and/or aspartate, serine and glycine, and at least one saturated straight chain fatty acid, a 2-oxo fatty acid, 3-oxo fatty acid or a 4-oxo fatty acid, wherein the fatty acid has a chain length of from C8 to C20 or of from C10 to C18. 
     
     
         14 . The method of  claim 13  wherein the lipopeptide toxin has a molecular weight, as determined by MALDI-TOF mass spectrophotometric analyses, of from about 1182 to about 1431 daltons, and comprising at least one fatty acid moiety covalently linked to the peptide, wherein said fatty acid moiety is a saturated fatty acid moiety of from C8 to C20, a straight chain saturated fatty acid moiety of from C10 to C18, or a 2-oxo-fatty acid moiety of from C8 to C20 or C10 to C18, a monounsaturated fatty acid moiety of from C8 to C20 or from C10 to C18, a 3-oxo-fatty acid moiety of from C8 to C20 or C10 to C18, or a 4-oxo-fatty acid moiety of from C8 to C20 or from C10 to C18. 
     
     
         15 . The method of  claim 14 , wherein said microorganism is selected from the group consisting of a gram-negative bacterium, a gram-positive bacterium and a fungus. 
     
     
         16 . The method of  claim 15 , wherein said controlling is by inhibiting growth, replication, or infectivity of said microorganism. 
     
     
         17 . A method for treating an infection caused by a microorganism in a subject, said method comprises the step of administering, to a subject in need of treatment therefor, a therapeutically effective amount of a mosquitocidal and/or antimicrobial composition comprising a lipopeptide toxin produced by the  Xenorhabdus  MT deposited with the American Type Culture Collection as PTA-6826, said toxin comprising histidine, diaminobutyric acid, asparagine and/or aspartate, serine and glycine, and at least one saturated straight chain fatty acid, a 2-oxo fatty acid, 3-oxo fatty acid or a 4-oxo fatty acid, wherein the fatty acid has a chain length of from C8 to C20 or of from C10 to C18. 
     
     
         18 . The method of  claim 17  wherein the lipopeptide toxin has a molecular weight, as determined by MALDI-TOF mass spectrophotometric analyses, of from about 1182 to about 1431 daltons, and comprising at least one fatty acid moiety covalently linked to the peptide, wherein said fatty acid moiety is a saturated fatty acid moiety of from C8 to C20, a straight chain saturated fatty acid moiety of from C10 to C18, or a 2-oxo-fatty acid moiety of from C8 to C20 or C10 to C18, a monounsaturated fatty acid moiety of from C8 to C20 or from C10 to C18, a 3-oxo-fatty acid moiety of from C8 to C20 or C10 to C18, or a 4-oxo-fatty acid moiety of from C8 to C20 or from C10 to C18. 
     
     
         19 . The method of  claim 18 , wherein the microorganism is selected from the group consisting of a gram-positive bacterium, a gram-negative bacterium and a fungus. 
     
     
         20 . The method of  claim 19 , wherein the gram-negative bacterium is  Pseudomonas aeruginosa, Escherichia coli, Salmonella enteriditis, Salmonella typhimurium, Salmonella agona, Listeria monocytogenes, Micrococcus luteus , or  Bacillus cereus , or wherein the fungus is  Candida albicans.