BACTERIOCIN PRODUCTION BY ERWINIA AMYLOVORA STRAINS

Combinations between 19 streptomycin sensitive (Str^s) and 7 streptomycin resistant (Str^r) strains of Erwinia amylovora, were examined for ability to produce bacteriocin specific to E. amylovora when grown on Luria-Bertani agar medium.

Antagonistic effect was prominent in most of the tested combinations between producer and indicator strains.
In contrast, a few combinations revealed variable results as far as antagonistic action is concerned.
Furthermore different genera and species of bacteria were not affected by inhibitor(s) produced by Str^s or Str strains of E. amylovora.

Studies on the nature of the inhibitor(s) produced by E. amylovora strains, showed the existence of prtein and absence of nucleic acid(s), reducing sugars and proteolytic enzymes, in the inhibitory zones around the growth of inhibitor(s) producing strains.

Either autoclaving gel pieces at 121°C for 20 min. or impregnating gel pieces taken from the inhibition zones with trypsin, pepsin or pancreatin, abolished the activity of the inhibitor(s) since the sensitive indicator strains of E. amylovora could grow on such treated gels.

From the present findings, it could be concluded that the inhibitor compound(s) produced by E. amylovora strains is defined as bacteriocin(s).

VII International Workshop on Fire Blight

A.A. Shoeib

https://doi.org/10.17660/ActaHortic.1996.411.47