فصلنامه دنیای میکروب ها
سال دوم شماره 1 (پیاپی 2، بهار 1388)

Typhoid is a worldwide disease. Salmonella Typhi is the most common agent causing typhoid. It is difficult to treat typhoid due to antibiotics multiple resistance and the bacterium is menace for future epidemic. Vaccination is the most successful method against this diseases. The aim of this study is isolation of Vi antigen from Salmonella Typhi Ty2 and evaluation of it immunogenicity in animal model. In this research, Salmonella Typhi Ty2 was cultured in Muller Hinton Agar Medium. After harvesting the cells and to suspention them into physiologic serum, polysaccharide capsule was extracted by precipitation with cetavlone. A mount of Nucleic acid in the sample were tested with Spectrophotometere at 260 nm and amount of protein were investigated with Bradford method and SDS-PAGE and the Immunodiffusion method were used to study of isolated Vi antigen. In final, immunogenesity of Vi antigen was tested in mouse. Amount of Nucleic acid and protein in the isolated sample were 0.08 µg/ml and 2.59µg respectively. In the SDS-PAGE, smear band of the Standard Vi was similar to isolated sample completely. The precipitation band in the Immunodiffusion method was confirmed to presence Vi antigen. In the study of Vi antigen on the mouse, 80 percent immunity was been created. Also injection in Rabbit showed that LPS level in the sample is not cause much fever. With regard to non producing the Human Vaccine of Typhoid in Iran, to be able use of this method for isolation of Vi antigen and introduce it as a vaccine candidate.

Cicer arietinum is the world`s third ranking and Iran`s first ranking legume in terms of amount of production. Mesorhizobium ciceri is the most important bacteria that has symbiosis with this plant and fixes nitrogen for this legume. The symbiotic Rhizobium of this plant are quite effective in fixing nitrogen molecule. Therefore the study of this phenomenon is great important. Atmospheric nitrogen fixation requires nitrogenase enzyme. nifH, nifD and nifK genes encode three polypeptides of the nitrogenase complex. After isolation of bacteria and culture, total DNA was isolated by using a standard protocol and it was used as template. The nifH gene was amplified from genomic DNA by PCR method with appropriate primers. Using two sets of primers nifH1/nifH2 and nifH4/nifD1, amplified products of the expected size were obtained on DNA extracted from M. ciceri. The amplified products obtained with the nifH gene was purified and sequenced. The nucleotide sequences of nifH gene of M.ciceri was performed. It shown 90% homology with the nifH gene in M.loti. This gene has also shown high homology with nifH gene in other Rhizobium species.

Backgorund and Johne’s disease is a chronic intestinal disease of domestic and wild ruminants that is caused by Mycobacterium paratuberculosis. So that Mycobacterium paratuberculosis is a widespread zoonotic disease, necessary to use prevention and control methods to eliminate this agent matter needs the attention of corresponding managers. The aim of this study is base on use of Nested PCR as an accurate and rapid method to detection of Mycobacterium paratuberculosis bovine feces. Fecal samples from 120 dairy cattle were collected and DNA extraction was performed from the samples. Then, samples were evaluated with specific primers for the Mycobacterium paratuberculosis-specific IS900 gene by Nested-PCR assay. Finally, PCR products were electrophoresis on agarose gel. In total, from 120 samples were enrolled in this study, 22 specimen (18.33%) were found positive on the basis of Nested-PCR analysis. Nested PCR technique is considered as a fast, reliable and affordable assay to detect Mycobacterium paratuberculosis

Industrial and agricultural activities have led to a substantial release of toxic heavy metals in the environment, which can constitute a major hazard for the ecosystem and human health.. Today, the use of microbial biomass for removal of heavy metals from aqueous solutions is gaining increasing attention. This study aims to evaluate the ability of the adsorption of heavy metal Zinc by four different biomasses (activated sludge of the systems of waste water refining, non-alcohlic carbonated soda industries, milk, herbal oil, and poultry slaughterhouse) and to determine the optimum conditions of pH for eliminating this metal from industrial waste water. The different values of this industries activated sludge added to 250mil Zinc solution of specific concentration. Then in different times, we took sample of the result solution and measuring the concentration of Zinc by atomic absorption method.This experimental repeated by solutions that their pH adjusted to 4 0.2, 5 0.2 and 6.5 0.2. Study of the results delineated that 30mil activated sludge of factories, non-alcohlic carbonated soda, Vegetable oil, Milk and poultry slaughterhouse within 150 min, about 82%, 33.4%, 48.9% and 51.5% of the initial concentration of Zinc in the solution was reduced, respectively. The comparison of Zinc absorption ability of active sludge in each industry in different pH showed that all of the mentioned industries sludge with pH=6.5 had the most ability in Zinc absorption. We can use this material to eliminate Zinc from waste water and their refinement, considering the low cost of the sludge substrast and also is availability. So adjusting the primary pH of solution, the out put of Zinc removal from solution in waste water treatment can be increased.

H. pylori is a spiral shaped gram negative non invasive bacterium which causes peptic ulcer and has an important role in gastric carcinoma and MALT associated lymphoma. The aim of this research is to assess sensitivity and specificity of Rapid urease test in comparison with PCR. 30 patients (test group) with peptic ulcer disease (PUD) and 30 patients (control group) with Non-Ulcer disease (NUD) were chosen from two central of endoscopy in Fars province during 2006. Endoscopy samples were examined by PCR and Rapid urase methods. In this study, PCR test considered as golden standard test. The assessment of infection sensitivity and specificity, PPV and NPV Rapid urease test for the test group were detected 76.67%, 80.76%,69.23%, 85.92%, 60.65% and in control group were 46.67%,52.94%,68.18%, 41.62% and 77.17% respectively. This study indicated that the Infection’s rate, sensitivity and specificity of Rapid Urase test acceptable in patients who are not under treatment. But the Infection’s rate, sensitivity and specificity of Rapid Urase test not acceptable in patients who are on Proton Pump Inhibitors (PPI) and treatment whit antibiotic. So complementary tests in these patients are recommended.

250 fecal swab sheep slaughtered in slaughterhouses Shiraz to isolate the bacteria E. coli O157 was selected. Prepared SMAC plates containing from 0.05 mg L-1 ceffexime and 2.5 mg L-1 potasium tellurite as standard (1S) to 6 time standard (6S). Certain pure E. coli O157 EDL933 was plated on SMACs. All plates incubated in 37°C over night. E. coli O157 was growth on all six SMACs, but all plates had grown with the same count in 1S to 3S plats. Some bacteria decreased according to dose of antibiotics. Two and four percent contamination rate was shown high sensitivity in 3 S than 1 S. use of media with high antibiotic deleted extra intestinal bacteria. We recommend using ICT-SMAC medium supplemented with 1.5 and 7.5 mg L-1 ceffexime and potassium tellurte respectively in spite of current SMAC to isolate E. coli O157 from clinical case

Development of methods without using plotant and poisonous material and minimum wastes to produce under control nano structures is of nanotechnologist concerns. In this way biologists, by previous knowledge, nano-scale minerals controlled making by microorganism, seeking organism capable making non-organic nanoparticles. The aim of this study is extracellular production of silver nanoparticles with maximum dimention of 20 nm by Fusarium oxysporum fungi. After studies to optimize growth condition, Fusarium oxysporum biomass in a medium containing yeast and malt extract is reproduced. After silver nanoparticles production in silver nitrate solution, this nanoparticles are studies by UV-Visible Spectrophotometry and Transmission Electron Microscopy (TEM) methods. Studies showed that when Fusarium oxysporum biomass put in 10-3 M of silver ions, can produce silver nanoparticles in the form of extracellular. Because of physical and chemical particular properties of silver nanoparticles with maximum diameter of 20 nm of Fusarium oxysporum fungi, its industrial production and applied evaluation is offered.

Diabet mellitus is a chronic disease. In this disorder, due to abnormal glucose metabolism, direct and indirect complications in many organ systems, including ocular, cardio-vascular, vernal, and cerebral and suppression of immune system have been occurred. Decreasing of both cellular and humoral immune system is a important factor for opportunistic infections. Prevention and control of these infections and recognize of their frequency and risk factor is very important. In this study, 118 diabetic patients that admitted in Islamic Azad University hospitals were included. Chief complaint of every patient, important finding in clinical examinations and results of microbial culturing from opportunistic infections had been analyzed. From 118 patients, 65 cases (55%) were female and 53 cases (45%) were male. Mean age of patients was 59.6 ± 11.7 years old and mean duration time of disease was 13.6 ± 7.8 years. Thirty one cases (26.1%) infected by opportunistic bacterial. From patient's samples (in microbial culturing), 12 cases (38.5%0 Escherichia coli, 9 cases (29%) fungal pathogens, 5 cases (16.3%0 staphylococcus aurous and 5 cases (16.3%0 Pseudomonas aeruginosa were isolated. Because of high frequency of infections in diabetic patients, using of preventing methods is important. On the other hand, diagnostic and treatment of these infections prevent from their complications.