الملخص

Abstract The present study includes utilization of the bacterial conjugation between the local isolate Bacillus subtilis and the laboratory strain Escherichia coli K-12 JM83 in order to determine the location of genes involved in production of polysaccharides in B. subtilis. The results revealed that in presence of glucose and lactose in growing media as a carbon source separately, the bacteria B. subtilis yield polysaccharides of 9.38 g/l and 2,51g/l respectively. After conjugation, the JM83 trans conjugation isolate showed a remarkable reduction in polysaccharides yield (1.00 g/l) after growing in media containing lactose and no significant increase of polysaccharides yield in presence of glucose (3.00 g/l) these results may indicate that the genes sharing in polysaccharides production in B. subtilis, may be located on its chromosomal DNA and not on its plasmid DNA.