Production of Antibacterial Substances by Pseudomonas glumae

Abstract

Forty eight strains of Pseudomonas glumae were tested for the antibiosis against 7 species of phytopathogenic bacteria, Agrobacterium tumefaciens, Clavibacter michiganensis subsp. michiganensis, Xanthomonas campestris pv. citri, X. campestris pv. oryzae, Erwinia carotovora subsp. carotovora, P. solanacearum, P. syringae pv. syringae. The productivity was tested using the plate chloroform method. All strains of P. glumae used in this study produced antibacterial substances against, at least, one indicator. The exudate from the culture plate obtained through freezing and thawing showed antibiotics against phytopathogenic bacteria used as indicators. While, no production of the antibacterial substances was observed in the various liquid media. However, in the agar-extract amended liquid medium, antibacterial substances were produced. These results indicated that water-soluble nutrients from agar will be necessary for the production of antibacterial substances. The antibacterial substances produced by P. glumae were dialyzable, heat labile and stable to trypsin, pronase, DNase, RNase treatments and UV irradiation.