Methicillin-resistant S aureus has progressed into an important pathogen of humans and is endemic in hospitals worldwide. MRSA strains carry multiple antibiotic-resistant genes. Recent work aim to investigate the prevalence of mecA gene among clinical isolates of MRSA .Fifty isolates of Staphylococci were demonstrated as methicillin resistancestaphylococcus aureus from various clinical specimens ( urine ,blood ,wounds ,and burns )after confirming their identity using morphological and biochemical tests ,as well as diagnosis by VITEK2 system. Also antibiotic sensitivity testing performed for all isolates by disc diffusion methods.Fifty isolates of S. aureus classified as MRSA taken from different clinical cases.mecA gene was detected by PCR technique to amplify 533bp using specific primers for the gene. The results showed that MecA gene was detecting in 39(78%) of Staphylococcus aureus isolates.Most of MRSA isolates were multiresistant to three antibiotic classes beta-lactams and multidrug resistant to other common antibiotics, such as aminoglycosides, therefore this work emphasis that there are other possible resistance mechanism may interact with mec A gene and causes development of methicillin resistance staphylococcus aureus

Streptococcus pneumoniae causes serious infections (pneumonia, meningitis and bacteremia) with significant morbidity and mortality rates. The goal of this study is to isolate and identify S. pneumoniae from clinical samples in Baghdad City hospitals in order to explore the presence of three virulence genes (lytA, ply and psaA) in clinical isolates. A total of 120 separate clinical samples were obtained from inpatients and outpatients with upper and lower respiratory tract infections at different hospitals in Baghdad. Twenty-five isolates of S. pneumoniae were identified by using cultural, morphological and biochemical characteristics as well as the diagnosis by VITEK2 system. Clinical samples were including sputum 19 isolates (76%) and urine 6 isolates (24%). The results of collected specimens showed that male's percentage is highest than female's patients, which was out of 25 isolates are 15 (60%) males and 10 (40%) females, The results also showed that it is much more common in elderly people than in younger people. The genomic DNA of bacterial isolates was applied in a polymerase chain reaction (PCR) to amplify certain genes. The PCR results were: Six isolates (24%) show positive results for the presence of lytA gene. Five isolates (20%) showed positive results for the presence of ply gene. Twenty-three isolates (92%) show positive results for the presence of psaA gene. As concluded from the present study, that the results exhibited that the presence of the virulence genes can be considered as a serious issue.

In recent years antibiotic resistance among Streptococcus pneumoniae strains has caused significant health problems worldwide. Current study was under taken to determine the antibiotic resistance patterns and to explore the presence of three antimicrobial resistant genes (erythromycin ribosomal methylase B ermB, macrolide efflux mef(A/E), and tetracycline resistance determinant tetM) in clinical isolates at different hospital in Baghdad city. The research was carried out at the University of Baghdad’s Institute of Genetic Engineering and Biotechnology for Postgraduate Studies, as well as in the laboratories of Baghdad hospitals. Twenty-five isolates of S. pneumoniae were identified by using cultural, morphological and biochemical characteristics as well as the diagnosis by VITEK2 system. All isolates studied were subjected to antibiotic sensitivity testing using the disc diffusion method. By Kirby–Bauer test. Using 10 antibiotics represented by Amoxicillin, Azithromycin, Chloramphenicol, Clarithromycin, Clindamycin, Erythromycin, Imipenem/EDTA, Levofloxacin, Tetracycline and Vancomycin. The resistance percentage of the isolates were 28%, 28%, 24%, 80%, 80%, 80%, 0%, 0%, 64%, 72% respectively. Genomic DNA was extracted from S. pneumoniae isolates and was applied in a polymerase chain reaction (PCR) to amplify certain genes. The PCR results were: fifteen isolates (60%) show positive results for the presence of ermB gene and the amplicon size was 745bp. Six isolates (24%) show positive results for the presence of mef gene and the amplicon size was 315bp. Twelve isolates (48%) show positive results for the presence of tetM gene and the amplicon size was 406bp. As concluded from the present study, that the results exhibited that the presence of the antibiotic resistance pattern can be considered as a serious issue.