Normally, bacteria exposed to antibiotics at sub minimal inhibitory concentrations (MIC) inside the host. Therefore, the current study aimed to comprehend the association among hemolysins, biofilm, as well as gentamicin resistance in local MRSA isolates. Around 35 Staphylococcus aureus locally isolated from different clinical specimens were employed in this study. Methicillin resistance was detected via cefoxitin disk diffusion and mecA amplification methods. MIC of gentamicin was estimated by broth microdilution method. Hemolysin genes involving hla, hlb, hld, and hlg were determined using multiplex polymerase chain reaction (PCR) technique. Microtiter plate method was employed for biofilm assessment in the presence and absence of gentamicin at sub MIC. Moreover, atomic force microscopy technique was employed for confirming the effect of gentamicin on biofilm. The present findings revealed that methicillin resistant S. aureus (MRSA) constituted, nearly, 94.29% (33 isolates) of all S. aureus isolates. Around 12 (36.36%), four (12.12%), and 17 (51.51%) isolates were gentamicin-sensitive, intermediate, and resistant to gentamicin, respectively. hla and hld were located in 32 out 33 MRSA isolates. All MRSA isolates succeeded in forming biofilm; however, three (0.09%), 23 (69.69%), and seven (21.21%) isolates formed weak,moderate, andstrong biofilm, respectively. Gentamicin at sub MIC reduced the intensity of biofilm and the AFM confirmed this finding. In conclusion, very weak correlation linked the biofilm formation capacity and isolate MIC. On the other hand, possession of hemolysin genes seems has no correlation with biofilm formation. Nevertheless, gentamicin at sub MIC reduced the intensity of MRSA biofilm.
The pathogenicity resulting from Staphylococcus aureus infection has remarkable importance as one of the community-associated bacterial infections, due to the virulent ability of these bacteria to produce biofilms. This study was designed to detect biofilm production in clinical isolates from samples of wounds and urinary tract infections. The expression levels of the icaA gene that is responsible of slime layer production in biofilms was compared in isolates with different biofilm producing capabilities. Fifty seven samples that included 32 samples from urine and 25 samples from wounds were collected from Alwasti Hospital, Al-Kindi Teaching Hospital, and Alzahraa Clinic, Baghdad, Iraq. The bacteria was identified accor
... Show MoreBiofilms formation by pathogens microbial Control considered important in medical research because it is the hazarded virulence factor leading to becoming difficult to treat because of its high resistance to antimicrobials. Glycopeptide antibiotic a (Vancomycin) and the commercial bacteriocin (Nisin A) were used to comparative with purification bacteriocin (MRSAcin) against MRSA biofilm. One hundred food samples were collected from Baghdad markets from July 2016 to September 2016, including (cheese, yogurt, raw milk, fried meat, grilled meat, and beef burger). All samples were cultures; S. aureus was confirmation by macroscopic culture and microscopic examination, in addition to biochemical tests. Methicillin resistance S. asureus (
... Show MoreMethicillin resistant Staphylococcus aureus (MRSA) is one of the principal nosocomial causative agents. This bacterium has the capability to resist wide range of antibiotics and it is responsible for many diseases like skin, nose and wounds infection. In this study, randomly amplified polymorphic DNA (RAPD)-PCR was applied with ten random primers to examine the molecular diversity among methicillin resistant Staphylococcus aureus (MRSA) isolates in the hospitals and to investigate the genetic distance between them. 90 Isolates were collected from clinical specimens from Iraqi hospitals for a total of 90 isolates. Only 10 strains (11.11%) were found to be MRSA. From these 10 primers, only 9 gave clear amplification products. 91 fragment l
... Show MoreEscherichia coli infections are becoming difficult treated because of extensive resistance to antibiotic among these organisms and manufacturing extended-spectrum beta lactamases enzymes (ESBLs) make them resistant to beta-lactam antibiotics. This study aims to offer a summary of the main horizontal transmission apparatuses between E. coli as well as Staphylococcus aureus and emergence resistance to antibiotics. Fifty of the E. coli and 50 of S. aureus isolates were examined to obtain minimum inhibitory concentration (MIC) results. These isolates were then tested by conventional polymerase chain-reaction for the existence or absenc
... Show MoreStaphylococcus aureus and Pseudomonas aeruginosa are the major globally distributed pathogens, which causes chronic and recalcitrant infections due to their capacity to produce biofilms in large part. Biofilm production represents a survival strategy in these species, allowing them to endure environmental stress by altering their gene expression to match their own survival needs. In this study, we co-cultured different clinical isolates of S. aureus and P. aeruginosa as mono- and mixed-species biofilms in a full-strength Brain Heart Infusion Broth (BHI) and in a 1000-fold diluted Brain Heart Infusion Broth (BHI/1000) using Microtiter plate assay and determination of colony-forming units. Furthermore, the effect of starvation stress on the e
... Show MoreTo elucidate the anti- Methicillin resistance Staphylococcus aureus (MRSA) effect of pomegranate alone and in combination with moxifloxacin fluoroquinolone. A total of five clinical isolates of MRSA (ATCC 43300) were used in the study. Disc diffusion method was used to determine the anti-MRSA effect of pomegranate and/or moxifloxacin by using Mueller-Hinton agar. Minimal inhibitory concentration (MIC), fractional inhibitory concentration (FIC) of moxifloxacin and pomegranate were calculated, the dynamic picture of the bactericidal effect of pomegranate and/or moxifloxacin was determined. SPSS version 20.00 was used for data analysis. Zone of inhibition (ZOI) of moxifloxacin was 19.67±4.84mm which was not significant compared with pomegrana
... Show MoreStaphylococcus aureus is a common pathogenic agent due to its ability to cause various types of infections, ranging from mild skin infections to sever systemic diseases. One of the most virulence factors of this bacterium is its ability to from biofilms on solid surfaces by anchoring the planktonic cells and by producing a protective layer of extra polymeric substances. Biofilm formation is controlled through many genes. The most important ones are icaA and icaD. Dentures are prosthetic devices that are made of different materials to replace lost teeth. The aim of this study is to examine the ability of different types of denture materials to support the biofilm formation of S. aureus at p
... Show MoreBiofilm formation represents one of the biggest problems facing scientists because of this phenomenon linkage with virulence of bacteria and other clinical environmental problems. In the present study, two clinical isolates,
Escherichia coli, and Staphylococcus aureus were exposed to the non thermal plasma for different intervals of time (1, 2, 4, 8, and 16 min). The biofilm was measured post exposing. It was found that 2 min. exposing to non-thermal plasma reduced the biofilm formation by both clinical isolates significantly. It can be concluded that the ability of S. aureus to form biofilm higher than E. coli and exposing for 2 min to non-thermal plasma sufficient to reduce the biofilm formati
The increasing use of antiseptic compounds creates selective pressure cause emergence of antiseptic resistance among Staphylococcus aureus .Resistance mechanism of antiseptic is driven mainly by multi drug resistant (MDR) efflux protein.Sixty five isolates of S.aureuswere collected from different clinical sources and subjected to 11 antibiotics most of them are recognized by efflux systems as extruded substrates. Range of efflux activity was estimated using cartwheel method. Simultaneous discrimination of antiseptic coding genes (qacA/B, smr and norA)as well as nuc and mecA genes among multidrug resistantS.aureus(MRSA) isolates was preformed using multiplex PCR assay
... Show MoreFoodborne diseases are a major risk for human health. Millions of people become sick as a result of eating contaminated food with microorganisms that cause diseases. S. aureus is considered as one of the most important pathogenic bacteria, having the ability to activate certain genes that encode for heat stable enterotoxins and cause Staphylococcal food poisoning. Thus, this study aimed to determine the prevalence of multi resistant Staphylococcus aureus that produce enterotoxins in different sources of food . Forty nine isolates were identified as S.aureus, according to morphological and biochemical tests. They were isolated from 387 different food samples from several randomly covered restaurants
... Show More