Geldanamycin-producing strains, uses thereof and methods of producing same

Abstract

A use of an inoculum of a geldanamycin-producing strain able to survive in a plant rhizosphere as a biocontrol of common scab affecting the plant and a method for biocontrolling common scab comprising the use of such strain. A biologically pure culture of a Streptomyces strain deposited at the American Type Culture Collection (ATCC) Accession number BAA-668, or a variant thereof.

1 .- 3 . (canceled) 
     
     
         4 . A method of biocontrolling common scab comprising applying on a plant an effective amount of an inoculum of a geldanamycin-producing strain able to survive in the plant rhizosphere. 
     
     
         5 . The method of  claim 4 , wherein said strain encodes a protein having the sequence of SEQ ID NO: 6 or an homologous sequence having geldanamycin activity. 
     
     
         6 . The method of  claim 4 , wherein said strain comprises the nucleotide sequence of SEQ ID NO: 7 or an homologous sequence having geldanamycin activity. 
     
     
         7 . The method of  claim 4 , wherein said strain comprises a nucleotide sequence able to hybridize under high stringency conditions to the complementary sequence of a sequence selected from the group consisting of:
 a) the nucleotide sequence of SEQ ID NO: 1;   b) the nucleotide sequence of SEQ ID NO: 2;   c) the nucleotide sequence of SEQ ID NO: 3;   d) the nucleotide sequence of SEQ ID NO: 5; and   e) the nucleotide sequence of SEQ ID NO: 7.   
     
     
         8 . The method of  claim 4 , wherein said strain comprises a nucleotide sequence able to hybridize under high stringency conditions to the complementary sequence of the nucleotide sequence of SEQ ID NO: 1. 
     
     
         9 . The method of  claim 4 , wherein said strain comprises a nucleotide sequence able to hybridize under high stringency conditions to the complementary sequence of the nucleotide sequence of SEQ ID NO: 2. 
     
     
         10 . The method of  claim 4 , wherein said strain comprises a nucleotide sequence able to hybridize under high stringency conditions to the complementary sequence of the nucleotide sequence of SEQ ID NO: 3. 
     
     
         11 . The method of  claim 4 , wherein said strain comprises a nucleotide sequence able to hybridize under high stringency conditions to the complementary sequence of the nucleotide sequence of SEQ ID NO: 5. 
     
     
         12 . The method of  claim 4 , wherein said strain comprises a nucleotide sequence able to hybridize under high stringency conditions to the complementary sequence of the nucleotide sequence of SEQ ID NO: 7. 
     
     
         13 . The method of  claim 4 , wherein said strain is a  Streptomyces  strain. 
     
     
         14 . The method of  claim 4 , wherein said strain is selected from the group consisting of  Streptomyces violaceusniger, Streptomyces hygroscopicus  and  Streptomyces melanosporafasciens  strains. 
     
     
         15 . The method of  claim 4 , wherein said strain is deposited at the American Type Culture Collection (ATCC) under Accession number BM-668. 
     
     
         16 . The method of  claim 4 , wherein said biocontrolling comprises reducing the severity of common scab. 
     
     
         17 . The method of  claim 4 , wherein said biocontrolling comprises reducing the incidence of common scab. 
     
     
         18 . A method for modifying the biocontrol efficiency of a bacterial strain comprising intraspecific protoplasm fusion of the bacterial strain with an other strain having a desirable biocontrol property against common scab. 
     
     
         19 . A method for making a biocontrol agent against common scab, which comprises the steps of:
 obtaining a microbial strain susceptible of producing geldanamycin;   contacting the nucleic acids or the proteins of said strain with a ligand specific to geldanamycin or to a nucleic acid encoding geldanamycin;   detecting the formation of a complex as an indication of the presence of geldanamycin or of a nucleic acid encoding geldanamycin in said strain,   whereby said strain or a geldanamycin-producing part of said strain may be used as a biocontrol agent against common scab.   
     
     
         20 . The method of  claim 19 , wherein said ligand is a nucleic acid having at least 12 nucleotides in length hybridizing with the nucleic acids having a sequence complementary to a sequence selected from:
 a) the nucleotide sequence of SEQ ID NO: 1;   b) the nucleotide sequence of SEQ ID NO: 2;   c) the nucleotide sequence of SEQ ID NO: 3;   d) the nucleotide sequence of SEQ ID NO: 5; and   e) the nucleotide sequence of SEQ ID NO: 7.