INTERNATIONAL JOURNAL OF MOLECULAR AND CLINICAL MICROBIOLOGY
Year:2018 | Volume:8 | Issue:1|Papers Count:10

Mycoplasma pulmonis and muris infections have been associated with several diseases in conventionally housed laboratory rat and mice colonies. In naturally infected of mycoplasma pulmonis in mice and rat colonies, the respiratory organ appears to be the favored site of colonization; so, it was not surprising to see that infection spread from the site of urogenital tract to the respiratory tract. In this research, PPLO broth culture and polymerase chain reaction (PCR) assay was used to detect Mycoplasma pulmonis and muris contamination in mice strain NIH. A new species of Mycoplasma muris (MYMORazi) have been identified in the nasopharyngeal, lung and vaginal samples of mice strain NIH in Razi Vaccine and serum research institute. Despite using two pair's specific primers targeting 16SrRNA gene of Mycoplasma pulmonis, detection was failed in both organs. We propose that the Mycoplasma muris strain MYMO Razi can cause infection in both organs of mouse strain NIH without presence of Mycoplasma pulmonis.

Regarding the role of nitrogen fixing microorganisms in soil fertility and plant growth, the use of biological fertilizers is a potential process in agriculture. Regarding toxic effects of silver nanoparticles on soil beneficial bacteria, the purpose of this study was to isolate and identify free-living nitrogen fixing bacteria from sunflower rhizosphere and investigation of the toxic effect of silver nanoparticles on the growth of isolated bacteria. In order to isolate nitrogen fixing bacteria, soil samples were obtained from sunflower rhizosphere and cultured in nitrogen-free medium at 30˚ C for 48 hrs. Then the production of 1-Aminocyclopropen-1-carboxylate (ACC) deaminase by the isolates was assayed by photometric method after growing in minimum DF medium containing ACC and aluminum sulfate. Phylogenetic identification of the selected bacteria was done using the amplification and sequence analysis of 16SrRNA gene. Finally, minimum inhibitory concentration (MIC) of colloidal suspensions of silver nanoparticles on the isolated bacteria was evaluated. The isolated bacteria from the soil samples of sunflower rhizosphere were included two species of nitrogen fixing bacteria with the ability for ACC deaminase production. Phylogenetic analysis of 16SrRNA gene resulted in identification of Azotobacter nigricans and an Azorhizophilus pasali. MIC of silver nanoparticles on both bacteria was evaluated as the concentration of 62. 5 ppm. Silver nanoparticles with the concentration above 62. 5 ppm had lethal effect on both studied nitrogen fixing strains. According to the importance of these bacteria in soil fertility and increasing utilization of silver nanoparticles in different industries, more studies on the dispersal of these nanoparticles in waters and waste waters and their penetration rates to agricultural environments seems necessary.

Antimicrobial agents are important compounds in reducing infections, but the spread of resistant pathogens diminished the effectiveness of these compounds. This study aimed to isolate the local bacterial pigments with specific antibacterial activity against clinical Acinetobacter baumannii isolates in burn centers. For this, pigmented bacteria isolated from environments in Fars province (Iran) and adjoining areas during Jun-July of 2017. Colonies with various pigment colors were isolated in pure cultures on nutrient agar. After identification of the pigmented bacteria, the extracted pigments were evaluated for antibacterial activity against previous confirmed clinical isolates of Acinetobacter baumannii with multi-drug resistant specification. Red pigment extract from Serratia marcescens (Prodigiosin) has the most proper inhibitory effect on the studied Acinetobacter baumannii isolates. The related bacterium was isolated from a salty region entitled Maharlo Lake. The minimum bactericidal concentration (MBC) and minimum inhibitory concentration (MIC) value of the pigment extracted from selected bacterium ranged from 2500-5000 μ g/ml and 1250-2500μ g/ml, respectively. The extracted pigments had a different antimicrobial activity against the studied clinical isolates, but on the basis of MBC/MIC results, the extracted prodigiosin pigment was the most effective anti-Acinetobacter agent. However, further studies are needed to use this pigment as a new antimicrobial agent or disinfectant on burn wounds.

One of the most prevalent zoonotic diseases is toxoplasmosis which is caused by an obligate intracellular parasite, Toxoplasma gondii, with a high global dissemination. Some species of birds are susceptible to T. gondii infection. To indirectly survey on T. gondii contamination of the rural and wild ecosystem of the Golestan Province, the presence of T. gondii antibody was examined in serum sample of 60 domestic rural ducks (Anas platyrhynchos domesticus) and 40 long-legged buzzard (Buteo rufinus) by MAT. Results: Out of 60 (32=male, 28=female) domestic ducks' serums, 38 (63. 3%) samples (20 male and 18 female) were diagnosed positive. There was no significant difference in the prevalence of anti-T. gondii antibody in male (60. 6%) and female (62%) ducks. Anti T. gondii antibody frequency was detected in 77. 5% (31 cases) of the sampled long-legged buzzards. Anti T. gondii antibody frequency in long-legged buzzard was significantly higher than domestic ducks. Conclusion: High seroprevalence of T. gondii infection in long-legged buzzards indicates high risk of T. gondii infection in rural and wild ecosystems of Golestan Province. Besides, the high levels of T. gondii contamination of sampled domestic duck highlights the importance of villagers' knowledge improvement about the important role of wild and domestic birds in the life cycle of T. gondii.

Moraxella catarrhalis is considered as one of the most significant pathogens of the respiratory tract. This research aimed to isolate and identify M. catarrhalis in respiratory diseases patients from northern part of Iran using culture and PCR techniques. In this study, 280 samples including throat swab of the patients with pharyngitis (n=92), sinus secretions of the patients with sinusitis (N=85), ear secretions of patients with otitis media (n=43) and pulmonary secretions of the patients hospitalized in the intensive care unit (n=60) were collected. Culture technique and phenotyping tests were used to isolate and identify the bacterium. PCR technique was also used for its identification by usage of the specific primers. Of a total of 280 samples, 27 samples (9. 64%), and 87 samples (31. 07%), were reported to be positive in terms of presence of M. catarrhalis using culture and PCR techniques, respectively. The results obtained by this study show that M. catarrhalis is present in the human societies and hospital environments. Therefore, rapid identification and tracking of its strains can play a significant role in prevention from their development.

Staphylococcus aureus is the most common pathogen causing nosocomial infections that their treatment by antibiotics is difficult. Biofilm potential of S. aureus is considered to be one of the main reasons for its survival and is influenced by many environmental factors. The purpose of this study was to evaluate the effect of pH on biofilm formation of S. aureus and its visualization by atomic force microscope (AFM). 100 S. aureus strains were isolated from clinical specimens of patients who were referred to Milad Hospital, Tehran and diagnosed by biochemical tests. A microtiter plate method was used to determine the strength of biofilm formation under acidic and alkaline pH. The effect of pH on biofilm formation was visualized by using AFM. In pH 7 and 9 the biofilm formation of S. aureus strains was at highest level, 78. 1% and 71. 9% but in pH3 and 12 was at lowest rate 35% and 35. 4%. There is a significant association between pH and biofilm formation. AFM microscopy analysis of effect of pH 3 and 12 in S. aureus showed reduction biofilm structures. In pH 7 and pH 9 more biofilm and less planktonic cells were observed. The increase or decrease in pH value was involved in decrease of biofilm formation. The AFM was a useful tool for visualization of S. aureus biofilm.

Sarcocystosis is a common protozoan infection in humans and animals which is caused by various species of Sarcocystis. Hence, the aim of this study was to evaluate strains of Sarcocystis parasites in carcass of 250 cattle and 250 sheep slaughtered in the Ardabil Meat Industrial Group. Carcasses were compared by macroscopic and digestion techniques, staining and non-staining tissue smear and molecular PCR-RFLP. The organs examined were diaphragm, intervertebral muscles, esophagus, heart and tongue. The results were analyzed using Chi-square test. Out of 250 cattle and sheep examined, 28 and 124 cases had macroscopic cysts and 162 and 211 cases had microscopic cysts, respectively. Of 28 cases of macroscopic cysts in cattle, 21 cases of S. hominis and 7 cases of S. hirsuta were diagnosed. In 100% (162) of bovine specimens containing microscopic cysts, S. cruzi was diagnosed. In 100% of sheep samples containing macroscopic cysts, S. gigantea was diagnosed. In 211 sheep samples containing microscopic cysts, 156 cases of S. arieticanis and 55 cases of S. tenella were diagnosed. We concluded that the studied meat of the Ardebil Meat Industrial Group is highly infected with Sarcocystis parasite. Due to the health importance and infection rate of this parasite, it is recommended to avoid consumption of half-cooked and grilled meat from cattle and sheep.

Chlorophenols are the most toxic pollutants of water and wastewater. Since 4-chlorophenol is a high soluble compound in water, it is found in water and wastewater abundantly. Because of high costs, high energy consumption and in some cases environmental inconsistency in chemical and physical removal methods, biochemical degradation of 4-chlorophenol is very important. In the present study, 13 strains of bacteria and 6 strains of yeast and mold were purified and isolated from wastewater treatment plant (Imam Khomeini seaport, Mahshahr), which lasted about 15 days. Then, the ability of each microorganism isolated in the presence of 100ppm of 4-chlorophenol was studied and two microbial species suitable for TY1 and TY2 were selected for use in mixed microbial culture. In this research, one of the most important factors affecting 4-chlorophenol degradation was by mixed microbial culture including glucose concentration with 2 and 5g/l was investigated. After examination, the microbial strains suitable for TY1 and TY2 were able to completely remove the 100ppm of 4-chlorophenol, so that the TY1 strain was removed completely after 45 hours and by TY2 strain after 21 hours and also, using a mixture of TY1 and TY2 strains (50/50) and in the presence of 2g/l glucose, 100ppm of 4-chlorophenol was completely removed after 18 hours. The significance and impact of this study was the use of indigenous strains isolated from wastewater treatment plant in petroleum refineries and petrochemical industries for the biodegradation of chlorophenol.

Many antibiotics are released into urban wastewater due to incomplete metabolism in humans and ultimately make their path to various natural environments. The use of antibiotics produces a selective pressure that requires antibiotic-resistant bacteria and resistant genes. Sulfonamides are released in aqueous media, the remainder, depending on the chemical activity of the bacteria, is activated against the bacteria and can evolve antibiotic-resistant bacteria (ARB) in the environment Promote natural microbial contamination. The present study evaluates the resistance of E. coli isolated to common antibiotics and especially sulfonamides, and also, since transmission of resistant genes to other bacteria is important in this study, the sul1 genes in E. coli was evaluated. During 5 months (September to December), 25 samples from 5 stations in Zarjob river, were collected. At the first, the MPN test was done, then the samples that were positive, were cultured in EMB and incubated for 24 hours. Antibiogram test was done according to disk diffusion method and CLSI. The serotyping, with multi antiserum kit of pathogenic E. coli was done. For extracting DNA, extraction kit, and PCR test was used to detect the sul1 gene from isolated E. coli. Finally, it was found that 20% of samples were resistance to sulfamethoxazole and all of them were belong to Group III (O128, O125, O44) and according to PCR all of them had sul1 gene. Antibiotic resistance has become a global issue. The most polluted river in the province of Giulan is Zarjob, which can cause pollution of various types of waters, aquatic organisms, fish and other marine organisms used by humans.

Staphylococcus saprophyticus is an important agent of urinary tract infections (UTIs), especially among young women. The aim of this study was to identify S. saprophyticus as a common cause of urinary tract infections and determine their antibiotic susceptibility. In this study, 51235 clinical samples were collected from therapeutic centers of Mazandaran. S. saprophyticus was confirmed by the real-time PCR technique through rrs gene and their antibiotic resistance pattern determined by disc diffusion method. Of the 51235 cultivated samples, only 2101 (4. 1%) cases had significant bacteriuria. In this study, the prevalence of S. saprophyticus was 2. 47%. Escherichia coli was the most common bacterium isolated from patients with UTIs at the rate of 61. 06%. S. saprophyticus showed the highest frequency of antibiotic resistance to erythromycin at the rate of 80% and ampicillin and cefotaxime were ranked with the frequency of 55 and 17. 5%, respectively. The present study shows that bacterial resistance is a potential problem in Mazandaran province.