الفهرس 
INTRODUCTION AND Aim Of The WorkOnly 14 pages are availabe for public view
 |  | from | 151 |  |  |
| | | from | 151 | | |
Abstract
The present work studies and investigates the mutagenic and the lethal effect of MNNG on three strains of E. coli, E. coli 07SKSO [B-1 isolated from a case of infantile gastroenteritis, E. coli 0S6K61 [B71 isolated from a stool of undiseased person and E. coli 026K60 [B6] isolated from a case of urinary tract infection. It was found that MNNG was completely lethal in all incubation periods in a dose of 15 mg / 5ml suspension of E. coli, and at a concentration of 10 mg / 5 ml suspension complete lethality for the three strains was obtained after 30 and 45 minutes incubation. As regard the mutagenic effect of MNNG on the three strain, it was found that the highest mutation rate was obtained from E. coli 07SKSO[B-] (isolated from a case of infantile gastroenteritis). There are eighteen mutants are isolated from this strain at a concentration of 2.5 mg MNNG/5ml bacterial suspension, Fifteen mutants After 15 minutes incubation and Three mutants after 30 minutes incubations. E. coli 026K60[B6],gives one mutant only isolated at a concentration of 1.25mg MNNG 15ml bacterial suspension after 30 minutes incubationNo mutants at all isolated.