الفهرس 
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Abstract
This study aimed to to take part in solving the pollution problem resulting from agriculture and sewage drainage by the bacteria living in some plants existing in polluted water in Nile delta ,hydrophytes namely, Eicohhornia crassipes, Myriophyllum spicatum, Ceratophyllum demersum, Lemna gibba and Potamogeton pectinatus, to remove various heavy metals (Cu, Cr and Pb). This study aims examine the ability of endophytic bacteria to remove various heavy metals (Cu, Cr and Pb). In this study, 85 isolate of bacteria were isolated from different parts of these plants. These isolates were selected for their dominance and unique disparities with others in colony morphology, and most were able to extract exopolysaccharides that give them the ability to form a gel-like network, which binds microbes together in biofilms, stimulates adhesion of biofilms to surfaces and protects microorganisms from conditions harsh environment. However, only 25 isolates could tolerate the presence of a concentration of 25% NaCl, all isolates (85) withstand the pressure of heavy metals (copper, chromium and lead) at a concentration of 150 ppm, while copper isolates 40 and 39 bacterial isolates were able to grow at 200 and 250 ppm, metallic chromium 27 and 22 bacterial isolates were able to grow at 200 and 300 ppm, on the other hand, 58, 42 and 22 bacterial isolates out of 85 bacterial isolates are able to grow on agar plates at a concentration of 200, 250 and 300 ppm, respectively. The effect of heavy metals on the growth kinetics of the isolates in the presence of lead and chromium ions on the nutrient medium showed a difference in the growth response according to the metal, while the growth kinetics of the isolates in chromium primacy was very weak so they were excluded and the isolate that showed a strong growth response under a pressure of 300 ppm was selected. Three of these seven isolates showed a good growth response in the presence of (100-500 ppm) lead ions. Based on the analysis of the 16S rRNA gene sequence of these samples, three strains of isolated bacteria were identified (Bacilus pumilus OQ629837, Bacilus cereus OQ569156 and Staphylococcus warneri OQ629838). As the biochemical descriptions of these isolates have been studied, Staphylococcus warneri can produce cellulose enzyme, proteolytic enzymes, exopolysaccharides and can fix nitrogen, Bacilus pumilus can produce amyloidase, cellulose enzyme, exopolysaccharide and Bacilus cereus can It produces proteolytic enzymes, cellulose enzyme, and lipolytic enzymes. Cellulocytes may assist in penetration and survival of the host plant. The isolates differ from microscopic examination in that they have different shapes, such as Staphylococcus warneri, the colony shape was irregular, while the shape of Bacilus pumilus and Bacilus cereus was circular. These bacteria could be promising candidates for the removal of heavy metals such as copper, chromium, and lead. As for the removal efficiency of strains for lead ions: (Staphylococcus warneri was 21.65%, Bacilus pumilus 33.8% and Bacilus cereus was 16.45% at a concentration of 20 ppm).