Gram-positive pathogens are causing many serious infections that affect humans and result in mild to severe diseases worldwide. In order to survive and initiate infection, enteric pathogens must resist the physiochemical defence factors in the human intestinal tract. One of these defence factors is bile, a potent antibacterial like compound in the intestine. Efflux pumps are the important mechanism by which bacteria resist antibacterial agents such as bile. Efflux of antimicrobial substances outside the bacterial cell is considered as a key factor for intestinal colonization and virulence of enteric pathogens. This paper will review the research conducted on efflux–mediated bile resistance in Staphylococcus aureus, Listeria monocytogenes, Enterococcus faecalis and Clostridium perfringens. These bacteria colonize in the human & animal gastrointestinal tract and they have a multiple mechanism to resist the innate defences in the gut and antibacterial activity of bile. However, bile resistance in these bacteria is not fully understood. The evidence from this review suggests that Gram-positive pathogens have the ability to active transport of bile. Further research is needed to know how these pathogens sense bile and how bile regulates its virulence factor. In general, therefore, it seems that understanding the specific mechanism of bile resistance in enteric bacteria including gram-positive pathogens may involve in the development of novel strategies to control and treatment of gastrointestinal infections.

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Background: Antibiotic resistant pathogens became a real global threat for human and animal health. This needs to concentrate the efforts to minimise and control these organisms. Efflux pumps are considered as one of the important strategies used by bacteria to exclude the harm materials out of the cell. Inhibition of these pumps can be an active strategy against multidrug resistance (MDR) pathogens. There are two source of efflux pump inhibitors can be used, chemical and natural inhibitors. The chemical origin efflux pump inhibitors have many toxic side effects while the natural origin characterized by a wide margin of safety for the host cell. Aim: In this study the ability of some plant extracts like (propolis show rosemary, clove, capsaicin and cumin) to potentiate the inhibitory activity of some antibiotics as (ciprofloxacin, erythromycin, gentamycin, tetracycline and ampicillin) against S. aureus pathogen were tested. Methods: Efflux pump inhibitory activity of the selected plant extracts were tested using ethidium bromide accumulation assay. Results: The results have shown that Propolis has a significant synergistic effect in combination with ciprofloxacin, erythromycin and gentamycin. While, it has no effect with tetracycline or ampicillin. Also, no synergic effect was noticed in combination of the MIC for the selected plant extracts (rosemary, clove, capsaicin and cumin) with any of the tested antibiotics. Interestingly, according to the results of EtBr accumulation assay, Propolis has potent inhibitory activity against S. aureus (MRS usa300) pump system. Conclusion: This study suggests that Propolis might act as a resistance breaker that is able to restore the activity of ciprofloxacin, erythromycin and gentamycin against S. aureus strains, in case of the Efflux-mediated antimicrobial resistance mechanisms.

Background and Objectives: Anaplasmosis is a zoonotic disease caused by Gram- negative bacterium from Anaplasmata- ceae family. Anaplasma causes high economic losses worldwide. 16S rRNA analysis was used to diagnose Anaplasma platys in Cattle. Phylogenetic tree and estimation of evolutionary divergence between A. platys isolates were performed. Materials and Methods: A total of 60 blood samples were collected from a cattle farm in AL- Diwaniyah province. 16S rRNA gene was identified using nested PCR. Overall, 40% of cattle that were chosen to collect the blood were identified to be infected with A. platys. Results: The results have shown presence of targeting partial region of 16S rRNA gene in 24 samples out of 60. Sequenc- ing results of 10 samples have revealed that the phylogenetic tree was divided in to two separate clades. Five isolates of A. platys- Iraq (accession no. OP646782, OP646783, OP646784, OP646790, and OP646791) were located in one clade with the A. platys- China (accession no. MN193068.1). While, five isolates (accession no. OP646785, OP646786, OP646787, OP646788, OP646789) were in different clade with two isolates of A. platys- Africa and A. platys- Zambia in distinct branch- es, close to the Rickettsiales. Conclusion: The phylogenetic study of A. platys sequences indicated that the isolates were collected from a cattle farm in Al- Dewaniyah were similar and close related to A. platys- China, A. platys- Zambia and A. platys- Africa). This study suggests that cattle can be considered a reservoir of A. platys.

Environment represents as a reservoir for emerging and disseminating of antibiotic resistance genes. Slaughterhouse waste is one of the important sources of antibiotic resistance genes (ARGs) even after treatment processes. This study was conducted to evaluate role of farm animal slaughterhouse in dissemination of antibiotics resistance in Al-Dewanyiah, Iraq. A total of eighty samples were collected from the central farm animal slaughterhouse. The detection was based on three mobile genetic elements and nine antibiotic resistance genes. The results showed that tetO & tetK are common resistance genes in the tested samples with great relative abundance 60%. While, MGE transposon (Tn3) was detected in 80% of the tested samples. Gene encoding resistance to quinolone, methicillin, aminoglycoside and β-lactamases were also detected in the tested samples. Presence of three class of integrons as a mobile genetic were tested and the results of type 1 recorded high abundance (P>0.05) as a compare with type 2 and type 3 integrons. Furthermore, concentrations of ARGs and MGEs per gram of sample were tested using qPCR. The genes encoding for tetracycline resistance and transposon (Tn3) were found in higher concentration (P>0.05) (copy number) per gram of slaughterhouse sediments comparing with the selected genes. Quantification of ARGs and MGEs in the slaughterhouse wastes indicates that those wastes represent as a hotspot for dissemination of antibiotic resistance to the environment. Low darning and no treatment for slaughterhouse wastes might increase abundance of ARGs and resistant bacteria in the natural environment.