Full Length Research Paper

Protoplasting impact on polyketide activity and characterization of the interspecific fusants from Streptomyces spp.

H. Lazim^1*, N. Slama¹, M. Abbassi ², I. Barkallah¹, A. Ben Hassen² and   F. Limam³

¹Unité de Microbiologie et Biologie Moléculaire, Centre National des Sciences et Technologies Nucléaires. Technopole de Sidi Thabet 2020, Tunis, Tunisie.

²Laboratoire de Microbiologie, Centre National de Greffe de Moelle osseuse, Bab Saadoun, Tunis, Tunisie.

³Laboratoire des Interactions Légumineuses Microorganismes, Centre de Biotechnologies de Borj Cedria, 95-2050 Hammam-Lif, Tunisie.

*Corresponding author. E-mail: hadeer.lazim@cnstn.rnrt.tn,   hadeer_lazim@yahoo.com, Tel: 00 216  20550070

Accepted 29 October, 2007

The influence of protoplasting and protoplast regeneration on antibiotic activity, transfer of biosynthesis encoding genes in local Streptomyces spp. CN207 was studied. The frequency of regenerated protoplasts in the lag phase was 1.7x10³ CFU/ml, in the beginning of the exponential phase 0.4x10² CFU/ml, in the exponential growth phase 2.5x10³ CFU/ml, and 1.0x10⁵ CFU/ml in stationary phase. The protoplast formation and regeneration technique resulted in a new isolate strain of Streptomyces spp.PR01 that produced approximately 5 fold more Streptomyces spp. CN207 antibiotic. The protoplast fusion resulted in increased isolation of variants with higher antibiotic activity. Recombinant Streptomyces coelicolor PF04 was increased 10 times more than the wild strain. The processes also affected on the strain resistance to some antibiotics but had no effect on the components of the antibiotic. The characteristics of this recombinant product were similar considerably to Streptomyces spp. CN207 product. Our data, in principal, indicate the possibility of transferring antibiotics cluster genes by fusion and provide a starting point for genetic and biochemical investigations of CN207 biosynthesis.

Key words: Streptomyces, polyketide antibiotic, gene transfer, protoplast regeneration, fusion.