دراسة بعض العوامل في انتاج الكواكيوليز Coagulase من المكورات العنقودية Staphylococci المعزولة محليا

Study of Some Factors Affecting Coagulase Production by Local Isolates of Staphylococci

The study include isolate and diagnosis the Coagulase Positive Staphylococci from clinical samples reached (102) sample of Hospitals Holy City of Kerbala (General Al Hussein Hospital and Kerbala Children Hospital) included Nasal swabs , Ear swabs , skin swabs , Burn swabs , Wound swabs ,Operation swabs and Urine sample ,as well as food samples and adopted collected from hawkers have not component cleanliness , which amounted to (35) sample ,which included food samples such as cheese , Dairy sample , samples of meat and ice cream sample for the period between (15 April  and 30 Jule  , 2014) .

Diagnosis of  isolates was done  according to tests of morphological and biochemical and after a diagnosis of colonies growth found that the bacteria positive for gram-stain formed ratio (٪69.98) for clinical samples and (٪57.89) for samples of food from the total isolates that gave the growth on culture media. And formed Staphylococci bacteria percentage (٪45.09) and (٪45.45) of clinical and food samples respectively, of the total isolates were positive for gram-stain. It also formed a Coagulase Positive Staphylococci ratio (٪39.13) of the total bacteria staphylococci acquired during isolation and diagnosis of clinical samples emerged as the percentage (٪60.0) of Coagulase positive staphylococci of total bacteria staphylococci in food samples. Also been diagnosed tow species of CPS (S. aureus and S. hyicus ) depending on the both types of Slide and Tube Coagulase Test as well as relying on other biochemical tests and Api staph system .

Also been tested the sensitivity of CPS toward antibiotic to determine the most effective antibiotic toward these bacteria and found that the Azithromycin antibiotic was the most effective antibiotic toward S.aureus in contrast of S.hyicus that found the Erythromycin antibiotic was the most effective antibiotic toward it. As shown bacteria S.aureus resistant clear to Erythromycin antibiotic as well as Ciprofloxacin antibiotic , as for the S.hyicus bacteria show obvious resistance to streptomycin antibiotic as well as for Gentamycin antibiotic. Been studying the different condition for the production of Coagulase enzyme for both species , it was noted that is a great similarity in those circumstances except for some difference , the results indicate that the chemical defined medium led to an increase in the production of the enzyme in both types under study , it was noted that the degree of appropriate temperature in the production of the enzyme is the same for both types, a temperature (37) C° it was noted that the pH, which led to increased production of the enzyme was identical for both types, a (7.5) and agreed both species in the  good production of the enzyme in incubation time (24 hrs.) , it also coincided result in good production of the enzyme in both species when using shaking incubator (100 rpm).

The difference observed in the productivity of the enzyme was that the bacteria S. aureus produce high amounts of the enzyme using rabbits and humans plasma and was also examined  that rabbits and sheep plasma were suitable in the production of the enzyme in bacteria S. hyicus It was also observed that the plasma concentration of 1/5 is appropriate in enzyme production of bacteria S. aureus, contrary to what was observed that 1/8 of the plasma concentration is appropriate in the production of the enzyme in bacteria S. hyicus As for the use of ion salts was observed that the use of magnesium ions salts (MgCl₂) leads to high production of the enzyme in bacteria S. aureus As for the bacteria S. hyicus was showed  that potassium ions (KCl) salts having high production also observed that sodium salts ions have a negative impact on the lack of production of both types.