Phenotypic and genotypic study of biofilm formation in multi-drug resistance Enterococcus species in Al-Najaf province, Iraq

Background: The objective of this work was to isolate and identify Enterococcus spp. responsible for various clinical infections in individuals, and to assess their ability to form biofilms. Objectives: This study detect bacterial taxa with antibiotic resistance. Recovered Enterococcus spp shown resistance to many antibiotics out of 17 examined antibiotics based on antibiotic susceptibility test. This study revealed that all isolated Enterococcus spp. under investigation were capable of producing strong biofilms when assessed by using the tissue culture plate technique, whereas the majority of bacteria were able to do so using the Congo red agar method. Methodology: 230 clinical samples were collected from both inpatients and outpatients who visited AL-Najaf facilities, including Al-Hakeem General Hospital, Al-Zahra'a Hospital for Childbirth and Children, and Najaf Teaching Hospital. Both male and female patients were among them, and their ages ranged from 3 to 69. Among the samples put on culture medium were MacConkey agar and blood agar. The Enterococcus sp. isolates were identified, isolated, and biochemically confirmed using standard procedures. Result: The result indicated that 28 Enterococcus spp isolated from 230 specimens. All these isolates (100%) were displayed a high ability to form a biofilm (bacterial adherence) through registered strong adherence reach 0.254 and above. However, data of spectrophotometer to Enterococcus isolate numbers 10 and 7, mean of adherence reach to 1.109 and 1.289 respectively. The findings of the CRA techniques, which involved growing all bacterial isolates on Cong red agar to identify biofilm development, revealed that 26 (92.8%) isolates of Enterococcus spp.