RESUMO
P. aeruginosa remains an important cause of life-threatening bloodstream infection in immunocompromised patients, particularly those with hematologic malignancies complicated by neutropenia. One of the most worrisome characteristics of P. aeruginosa consists is its low antibiotic susceptibility. This low susceptibility is attributable to concerted action of chromosomally-encoded multidrug efflux pumps genes. These genes are often controlled by regulatory gene located on the same operon of efflux pump. One of particular significance is the MexAB-OprM efflux system, which is expressed constitutively, thereby contributing to the well-known intrinsic resistance of this organism to multiple antimicrobials. To detect the occurrence of mexAB-OprM operom on the chromosomes of septicemic P. aeruginosa[SPA]. This study was include 53 Pseudomonas aeruginosa isolates isolated from patients their ages ranging from two days to 73 years,28 males and 25 females. Some of the isolates were isolated from acute, 15[28.3%], and chronic, 7 [13.2%], leukemic patients, 5 [9.4%] from each lymphoma and gastrointestinal neoplasms patients. Nine [17%], 3[5.7%], 6 [11.3%] and 3[5.7%] from urogenital neoplasms, breast cancer patients, septicemic patients due to burn infections and neonatal septicemia respectively. Chromosomal DNA was extracted from SPA isolates and subjected to PCR to amplify three genes of mexAB-OprM efflux pump. Multiplex PCR of mexAB-OprM efflux pump genes revealed that 53 [100%] were positive to all three genes of operon, mexA, mexB and the regulatory gene, mexR. P. aeruginosa can cause septicemia in cancer patients and other compromised patients, like patients suffering from extensive burns and neonatal infants. mexAB-OprM efflux pump genes are a chromosomal encoded genes and can be used as a markers in identification of SPA by molecular methods. These genes can be used individually or collectively in rapid identification of SPA, and rapid detection for mexAB-OprM efflux pump occurrence on their chromosomes
RESUMO
Transfer RNA is a type of RNA which during protein synthesis Act as an adaptor molecule, matching amino acids to their codons on mRNA. tRNA also functions in the formation of cross links during peptidoglycan synthesis. The aim of this study is that, extraction of tRNA from uropathogenic Escherichia coli then detect the presence of such molecules after extraction and measure the purity of the tRNA extract solutions. Thirty uropathogenic E.coli isolates were isolated from hospitalized and non hospitalized patients, complaining of urinary tract infections, of Al-Kadhymia Teaching Hospital and subjected to tRNA extraction. A method of tRNA extraction was modified by adding sodium dodecyl sulfate [SDS] instead of urea. Polyacrylamide gel electrophoresis and two methods of staining, ethidium bromide staining and silver staining, as well as spectrophotometric detection were used. Ethidium bromide stained gel reveals bands with molecular weight less than yeast rRNA .Silver stained gel shows bands with molecular weight less than ova albumin[45000 dalton] but with approximate molecular weight of chymotrpsinogen[24000 dalton]. The tRNA extracts were relatively pure with the modified method of extraction. In the present study, a modification of polyacrylamide gel electrophoresis to detect tRNA and to determine their molecular weigh was applied