Bacteriocins Contributing in Rhizospheric Competition among Fluorescent Pseudomonads
Samia Mezaache-Aichour *
Laboratory of Applied Microbiology, Faculty of Life and Natural Sciences, University of Sétif 1, Sétif, Algeria.
Nora Haichour
Laboratory of Applied Microbiology, Faculty of Life and Natural Sciences, University of Sétif 1, Sétif, Algeria.
Abdelhadi Guechi
Laboratory of Applied Microbiology, Faculty of Life and Natural Sciences, University of Sétif 1, Sétif, Algeria.
Jane Nicklin
School of Biological and Chemical Sciences, Birkbeck College, University of London, Malet Street, London WC1E 7HX, UK.
Mohamed M. Zerroug
Laboratory of Applied Microbiology, Faculty of Life and Natural Sciences, University of Sétif 1, Sétif, Algeria.
*Author to whom correspondence should be addressed.
Abstract
Aims: To examine the production of bacteriocins through the study of a group of rhizospheric Pseudomonas isolates already known to produce metabolites that are antagonistic to fungi.
Methodology: Fourteen rhizospheric strains of fluorescent Pseudomonads spp., were tested as well as two referenced strains Pseudomonas protogens CHA0 and Pseudomonas aureofaciens 30-84, for their ability to produce induced bacteriocins. The induction is carried out first by UV light, and secondly by mitomycin C.
Results: In addition to the reference strains, six isolates were found to produce bactericidal substances after UV light induction against Pseudomonas target bacteria but also against other genera (Escherichia and Staphylococcus). Producing strains were treated with mitomycin C, and then lysed with chloroform. Analysis of the lysates by trypsin and freezing treatments, suggests that the active compounds are of high molecular weight.
Conclusion: It is therefore suggested that these bacteria could be good competitors for their introduction as biocontrol agents.
Keywords: Biocidal induced molecules, establishment, proteases resistance, non-pathogenic soil bacteria