Paenibacillus strain, antifungal compounds, and methods for their use
The present invention relates to a composition comprising a biologically pure culture of a fungicidal Paenibacillus sp. strain comprising a variant fusaricidin synthetase lacking a functional adenylation domain in the third module. The present invention also provides a composition comprising a biologically pure culture of a fungicidal Paenibacillus sp. strain or a cell-free extract thereof comprising at least one Paeniserine and at least one Paeniprolixin. Also provided are isolated compounds and methods of treating a plant to control a plant disease with the disclosed compositions and compounds.
1. A composition comprising a compound having the structure
wherein
(a) R 1 is —CH 2 OH; R 2 is —CH 2 C(O)NH 2 ; and R 3 is H;
(b) R 1 is —CH 2 OH; R 2 is —(CH 2 ) 2 C(O)NH 2 ; and R 3 is H;
(c) R 1 is —CH 2 OH; R 2 is —(CH 2 ) 2 C(O)NH 2 ; and R 3 is CH 3 ,
(d) R 1 is —CH(OH)CH 3 ; R 2 is —CH 2 C(O)NH 2 ; and R 3 is H; or
(e) R 1 is —CH(OH)CH 3 ; R 2 is —(CH 2 ) 2 C(O)NH 2 ; and R 3 is H
including salts, hydrates, solvates, polymorphs, optical isomers, geometrical isomers, enantiomers, diastereomers and mixtures thereof.
2. The composition according to claim 1 , wherein the compound having the structure (II) is
3. The composition of claim 1 , wherein the composition is a fermentation product of a Paenibacillus sp. strain.
4. The composition of claim 3 , wherein the Paenibacillus sp. strain comprises a variant fusaricidin synthetase lacking a functional adenylation domain in the third module (FusA-A3), and
wherein the lack of a functional FusA-A3 inhibits synthesis of fusaricidins with a tyrosine or a phenylalanine at amino acid residue (3) compared to synthesis of fusaricidins by a Paenibacillus sp. strain comprising a wild-type fusaricidin synthetase.
5. The composition of claim 3 , wherein the fermentation product further comprises a formulation ingredient selected from the group consisting of a wetting agent, extender, solvent, spontaneity promoter, dispersant, frost protectant, thickener and adjuvant.
6. The composition of claim 4 , wherein the variant fusaricidin synthetase comprises an amino acid sequence exhibiting at least 90% sequence identity to SEQ ID NO: 10.
7. The composition of claim 6 , wherein the Paenibacillus sp. strain is Paenibacillus sp. strain NRRL B-50972, Paenibacillus sp. strain NRRL B-67129, or a fungicidal mutant strain thereof.
8. The composition of claim 1 , further comprising a fusaricidin.
9. The composition of claim 8 , wherein the fusaricidin is fusaricidin A.
10. The composition of claim 9 , wherein the compound having the structure II is
11. The composition according to claim 8 , wherein the weight ratio of the fusaricidin and the compound having the structure (II) is in the range of 1:1000 to 1000:1.
12. A method of treating a plant to control a disease, wherein the method comprises applying an effective amount of the composition according to claim 1 to the plant, to a part of the plant and/or to a locus of the plant.
13. The method of claim 12 , wherein the method comprises applying the composition to foliar plant parts.
14. The method of claim 12 , wherein the disease is caused by a fungus selected from the group consisting of Alternaria alternata, Alternaria solani, Botrytis cinerea, Colletotrichum lagenarium, Fusarium culmorum, Phaeosphaeria nodorum, Zymoseptoria tritici, Phytophthora cryptogea, Phytophthora infestans, Pythium ultimum, Magnaporthe oryzae, Thanatephorus cucumeris, Ustilago segetum var. avenae, Uromyces appendiculatus , and Puccinia triticina.
15. The method of claim 12 , wherein the disease is a mildew or a rust disease selected from the group consisting of powdery mildew, downy mildew, wheat leaf rust, leaf rust of barley, leaf rust of rye, brown leaf rust, crown rust, and stem rust.
16. The method of claim 12 , wherein the disease is caused by bacteria selected from the group consisting of Xanthomonas campestris, Pseudomonas syringae , and Erwinia carotovora.