Studies with two uropathogenic urease-producing Escherichia coli strains, 1021 and 1440, indicated that the urease genes of each are distinct. Recombinant plasmids encoding urease activity from E. coli 1021 and 1440 differed in their restriction endonuclease cleavage sites and showed minimal DNA hybridization under stringent conditions. The polypeptides encoded by the DNA fragments containing t...

abstract microbial contaminants transport to groundwater is a serious environmental problem that can result in large outbreaks of waterborne diseases. some of bacteria can travel from vadose zone and cause contamination of groundwater resources. thus, an accurate prediction of transport and fate of pathogenic microorganisms in unsaturated soil is needed to protect groundwater resources. the mai...

a total number of 259 gram negative bacteria (entero-bacteria) isolated during the years 1973-1974 was examined. these strains were isolated from sick children referred and or hospitalized in a children hospital in tehran. the strains consisted of ; 131e.coli, 52 salmonella, 40 klebsiella, 18 shigella, 13 proteus, 3 enterobacter and 2 citrobacter. sensitivity tests were performed according to t...

bacterial utilize a multitude of methods to secretion of specific substrate across phospholipid membranes. these bacterial strategies can play many roles in promoting bacterial process, from enhancing pathogenesis to bacterial response to environmental condition. the secretion in bacterial species transfer and release performance substance such as proteins, enzymes and metabolites to environmen...

conclusions the results showed that some patients were probably contaminated with nonbacterial and nonparasitic agents. all the parasitic isolates were resistant to most antibiotics. therefore determination of microbial isolates and antibiotic susceptibility is necessary before treatment procedures. results of 2376 patients, 466 (19.6%) were contaminated with pathogenic bacteria or protozoa.the...

in western countries there is a growing incidence in obesity, inflammatory bowel disease (ibd) and colorectal cancer (crc), which places an increasingly important burden on the health care system. in the current decade, changes in intestinal microflora (i.e., dysbiosis) are likely the result of environment factors such as food, lifestyle, and medications which have been shown in obesity and ibd...