التحييد بالحرارة و تأثيره على محتوى DNA البلازميدي في ثلاثة أجناس مختلفة من البكتيريا

الملخص EN

The current study has included isolating and recognizing the symbiotic bacteria “Sinorhizobium meliloti” from the rooted nodules forming on Trigonella foenumgraecum L.

growing in the field and the pathogenic bacteria to man "Pseudomonae aeruginosa" in the field of soils, beside the results mentioned in the bar API 20E.

It also used the pathogenic bacteria to the plant “Agrobacterium rhizogenes”, R1601, genetically engineered by its resistance to the two antibiotics Kanamycin (Kan Res+) and the Carbenicillin (Car Res+), and study the effect of curing by heat at 440 c on the plasmid content DNA in the three bacterial genders and upon the special apparent specifications of each, and it has appeared that the physical curring had a big effect upon losing S.meliloti bacteria and P.aeruginosa the feature of resistance of some antibiotics, while the heat didn’t affect in losing the resistance feature in A.rhizogenes bacteria for the used antibiotics Amoxicillin, Ampicillin, Cefotaxime, Chloramphenicol, Trimethprim, also it had effect on the losing of S.meliloti bacteria for its feature of production from the Exopolysaccharides without the other genders,