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 ability of microorganisms to attach to living and non-living surfaces and create a biofilm is the cause of numerous long-lasting illnesses, as well as their strong resistance to drugs. Bacterial biofilms consist of intricate assemblies of immobile bacteria. These are located in an extracellular matrix and adhere to various surfaces for a long period. The present study evaluated the antibacterial effectiveness of Plantago major extract against Staphylococcus aureus biofilm. The specimens analyzed in this investigation were skin infections of clinical origin. The current study was not previously studied, particularly in terms of S. aureus biofilm breakdown and inhibition. The disc diffusion method was used to test the antimicrobial activi
... Show MoreThe ability of microorganisms to attach to living and non-living surfaces and create a biofilm is the cause of numerous long-lasting illnesses, as well as their strong resistance to drugs. Bacterial biofilms consist of intricate assemblies of immobile bacteria. These are located in an extracellular matrix and adhere to various surfaces for a long period. The present study evaluated the antibacterial effectiveness of Plantago major extract against Staphylococcus aureus biofilm. The specimens analyzed in this investigation were skin infections of clinical origin. The current study was not previously studied, particularly in terms of S. aureus biofilm breakdown and inhibition. The disc diffusion method was used to test the antimicrobial activi
... 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 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 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 phenotypic level by detecting ba
... Show MoreStaphylococci are common commensals in human beings, yet certain species are pathogenic. Staphylococcus aureus, particularly, is a very virulent human pathogen. The capacity of staphylococci to sense the density of bacterial cell, i.e., quorum, and thereafter respond via genetic modifications is attributable to one primary mechanism known as accessory gene regulator (Agr). Agr's extracellular signal is a peptide that is posttranslationally modified with a thiolactone molecule. Agr is in charge of the upregulation of numerous exotoxins and hydrolyzing enzymes, as well as the downregulation of many colonization determinants, under circumstances of high cell density. This modulation is critical for the scheduling synthesis of virul
... Show MoreThe current study aimed to investigate the viability of biofilm formation klebsilla pneumoniae and Staphylococcus aureus. 440 urine samples were collected from patients suffering from urinary tract infection (UTI) from those who were admitted and visitors to Al-Ramadi Teaching Hospital, Al-Yarmouk Teaching Hospital, Al-Ramadi Teaching Hospital for women and children and , Teaching Laboratories in the Medical City for both genders for a period extended from 5 July, 2017 to 10 October, 2017. Samples were diagnosed by culturing them on a selective media and by biochemical testes , also, diagnosis was ensured by using VITEK-2 compact system. Results showed that K.pneumoniae isolation ratio was 17.1%(68) and S.aureus ratio was 13.1%(52). Thei
... Show MoreVancomycin Staphylococcus aureus (VRSA) is a strain belonging to S. aureus that is considered the main cause of bacterial skin and soft tissue infections. It has acquired resistance to vancomycin and represents a therapeutic challenge. The current study aimed to compare the possible therapeutic effects of VRSA bacteriocin (VRSAcin) on the treatment of skin infection in mice compared with an antibiotic (linezolid). The results showed that from fifty swabs obtained from human skin wounds, only 30 samples were identified as Staphylococcus spp., and 20 samples of them were identified as VRSA strains. One isolate was selected for VRSAcin extraction depending on its antibiotic resistance using an
The aim of this research is to evaluate the effect of glucose and sodium chloride on biofilm formation by bacteria causing wound infection. For this purpose, 1% and 2% concentration of each of glucose and sodium chloride were used to test the biofilm formation potential of Staphylococcus aureus and Pseudomonas aeruginosa, which were the most common abundant bacteria that cause infection by biofilm. Each of the concentrations was kept in contact with the pathogenic bacteria for 24 hours. After the period of incubation, the concentration of 1% of glucose enhanced moderate biofilm formation capacity for (66% and 80%) on both bacteria respectively. The concentration of 2% glucose, on the other hand, led to a weak biofilm fo
... Show MoreBetween October and December 2018, 27wounds and burn swab specimens were collected by laboratories at Al-Yarmook hospital, and cultured on Mannitol salt agar. the isolate was subjected to Nd: YAG laser in different power (400mJ, 500mJ, 800mJ and 900mJ). In general the laser showed effect on bacterial growth that reach to complete killing, the statistical analysis showed that there is weak correlation between laser at 400mJ with killed percentage. While in 500mJ its exhibit complete correlation with killing percentage, this correlation was decreased with increasing in power to 800mJ and 900Mj.