JOURNAL OF MICROBIAL BIOTECHNOLOGY
Year:2012 | Volume:4 | Issue:13|Papers Count:8

Background and Objective: Infection of T cells by human T cell lymphotropic virus type1 (HTLV-1) immortalizes these cells as a prelude to adult T cell leukemia (ATL). Transformation of T cells in the early phases is mediated by the HTLV-1 Tax protein. Khorasan province, and particularly Mashhad is an endemic area for HTLV-1 with an incidence of approximately 5%. Tax protein is useful to produce diagnostic kits for screening of infections, and it can also be applied for to following up anti-Tax antibodies in patients. Therefore the purpose of present research was to produce of Tax protein which is a good immunogen.Materials and Methods: After transformation of E.Coli with plasmid containing Tax gene, PCR reaction was done to determine whether transformation was occurred. Then, transformed bacteria were grown on LB medium and the expressed protein was precipitated with ammonium sulfate. Immunoaffinity chromatography was used to protein purification, and silver staining and dot blotting were used for the characterization of Tax protein.Results: Results of PCR reaction done with tax gene specific primers showed bacterial transformation, and also the results of silver staining and dot blotting showed the purified Tax protein which was done by affinity chromatography.Conclusion: The results show that although Tax protein was produced by this method, the amounts of the produced protein were low.

Background and Objective: Symbiodinium is a genus of unicellular algae (Dinoflagellae) that may occur as symbiont in other marine invertebrates such as hard corals and free living in the pool. So far, 11 species belonging to Symbiodinium have been identified based on morphological characteristics. Since the morphological characteristics of this species are not the same with its physiological function, using molecular methods, 9 clades of Symbiodinium called A to I, have been identified.Materials and Methods: In the present study, specimens of Corals were collected from 3 colonies in 3 replicates and free living specimens were collected from corals overlaying waters in three replicates off Larak Island, northern part of Persian Gulf. Symbiodinium were removed and the slurry was preserved in DMSO buffer (20% Dimethyl Sulfoxide in NaCl saturated). DNA was extracted. ITS2 region was amplified by polymerase chain reaction (PCR).Results: The gene sequences showed that Corals harbored Symbiodinium clade A. and clade of free living Symbiodinium also is clade A.Conclusion: In this study, Clade A sighting is reported for the first time in the northern parts of the Persian Gulf. So far clade D only been reported from the Larak Island. Since Clade D is resistant to environmental conditions. This suggests a change in the diversity of zooxanthellae clades located in the inner parts of the Persian Gulf toward the Oman Sea where oceanic conditions dominate.

Background and Objective: The pollutions of petroleum industries in environments are removed during relatively long time. Providing optimum conditions for oil degrading microorganisms would increase more efficiently removal rate of these contaminants. The aim of this study was to isolate the best oil degrading bacterium for applying on bioremediation process.Materials and Methods: To find this objective, sampling was done from soils contaminated with crude oil and the best strain isolated and named Abt1. Then, oil degrading tests were performed under the different conditions.Results: Biochemical tests and 16s rDNA analysis showed that Abt1 belonged to Planococcus with 100% similarity to a strain with Accession GU213131 in Genebank. This strain was able to grow at presence of 0-7% NaCl and tolerates pHs between5 to 8. The optimum conditions for petroleum biodegradation were pH 7.5, NaCl 0% and temperature around 30oC. Also minimum nitrogen and phosphate needed for degrading 1g crude oil were 0.292 and 0.036g/l respectively.Conclusion: This strain was able to degrade 1g crude oil during 12 days. Because the environments contaminated with oil hydrocarbons have the different salt contents, halotolerant microorganisms could increase treatment rate of contaminants. Therefore, this halotolerant strain could be used to remove pollutions from water and fields.

Background and Objective: Anthrax disease is caused by Bacillus anthracis. Bacillus anthracis has pXO1 plasmid and pXO2 plasmid. PXO1 plasmid is responsible for toxin production and the pXO2 plasmid is synthesized capsule. The purpose of this study has been examined for presence the gene Pxo in Bacillus subtilis, Bacillus cereus and Bacillus thuringiensis.Materials and Methods: In this cross sectional, 65 soil samples collected from across the country and biochemical tests were performed then The plasmid was extracted. Using specific primers Toxin gene in pXO1 plasmid and gene capsule in pXO2 plasmid Examined.Results: From 65 Soil samples were collected 31Bacillus were isolated. They were 19 Bacillus cereus, 12 Bacillus subtilis and also7 Bacillus donated that Includes 2 Bacillus cereus and 2 Bacillus subtilis and were 3 Bacillus thuringiensis. From whole Bacillus isolated Only 13 Bacillus cereus has bond toxin encoding gene (pXO1). Band coding capsule gene (pXO2) has not in the case of Bacillus.Conclusion: This study showed that pXO1 plasmid has been transferred from Bacillus anthracis to the Bacillus cereus in Iran but none of the items had been done.

Background and Objective: Urinary tract infections (UTIs) are one of the most common infectious diseases that E. coli is the major causative pathogen. Phylogenetic analyses have shown that E. coli strains fall into four phylogenetic groups (A, B1, B2 and D). This study aimed to define the phylogenetic groups of E.coli isolated from urinary tract infections.Materials and Methods: This study was carried out on the patients of suspected urinary tract infection. Specific biochemical and microbial tests were used for identification of isolated bacteria. The phylogenetic groups of E.coli strains were determined by Multiplex PCR technique of two genes (chuA and yjaA) and a DNA fragment (TSPE4.C2). After electrophorese, strains were divided in phylogenetic groups based on the presence or absence of genes and a DNA fragment.Results: Out of 100 identified E. coli, the most common identified groups were classified as B2 (65%), D (19%) and A (16%), and none of the species belonged to the B1 group. According to the findings of this study, most of the extra-intestinal pathogenic strains of E. coli isolated from urinary tract infections belonged to phylogenetic group B2.Conclusion: The results showed that the molecular phylogenetic typing method based on PCR of genes and a DNA fragment is a simple and rapid method in typing of E. coli strains. Also this technique uses for understanding about pathogenesis of infections, hospital infections control and epidemiological studies.

Background and Objective: Due to daily increasing demand for lipid sources with potential of conversion to biodiesel, much effort has been done to find microbial oil resources. This oil is similar to plant's oil and it will be economical if low cost substrate use. Using agricultural wastes attracted a lot of attention for producing microbial lipid nowadays. Between this environmental wastes, grass that gain from environment, has potential of conversion to high value products.Materials and Methods: In this study designing of experiments based on Taguchi method was used to optimize parameters related to use of grass as substrate for gaining highest lipid production. Analysis of lipid production was done by GC-MS method.Results: After optimization of condition highest lipid production and lipid content of 6.8g/L and 55% was gained respectively and biodiesel yield was 79%. The highest fatty acids were Palmitic acid & Oleic acid that were produced 18.51% and 67.29% respectively.Conclusion: According to the results of this investigation environmental wastes can be converted to valuable materials by using oleaginous yeasts. Also the composition of the extracted oil shows that it has potential for biodiesel production.

Background and Objective: Soil-derived microorganisms have proven to be a useful source of natural antimicrobial compounds. By antagonistic activity of B.pumilus species against some phytopathogens and antimicrobial activity against pathogenic bacteria and fungi, this study was designed with the aim of evaluation of antimicrobial activity of isolate and standard strain of B. pumilus against two phytopathogens P. carotovorum and Xanthomonas campestris and three human pathogens C.albicans, B.cereus and Ps. aeruginosa and optimization of conditions of antimicrobials production.Materials and Methods: For isolation of B.pumilus species serial dilution agar plate technique, biochemical tests and antibiotic susceptibility assay were used. For the initial study of antagonistic activity, trypticase soy broth medium and agar disk diffusion methods were used; and for production of antimicrobial compounds, synthetic medium and agar well diffusion method were used. Then, optimization of conditions of antimicrobial compounds production was evaluated by the change of parameters like pH (6-9), glucose concentration (1-5%) and incubation period (0-72 hours). Data were analyzed using SPSS and statistical tests of variance analysis (ANOVA).Results: Isolate and standard strain of B.pumilus showed better antimicrobial activity against Gram-positive human pathogen compared to other test microorganisms. Maximum production of antimicrobial compounds was obtained at pH 7, 3% glucose and after 48 hours of incubation at 37oC against target microorganisms. Also, a significant relationship between change of pH and glucose concentration of the culture media and incubation period for more production of antimicrobial compounds was observed (P<0.05).Conclusion: The results showed that type and compositions of used media and external factors like pH and incubation period are effective on more production of antimicrobial compounds of B. pumilus.

Background and Objective: Although using antibiotics made a superior progress in medicinal industry, but their massive and false prescription results bacterial resistance to consumption antibiotics. So using one method for specifying sensitivity is not trusty alone. The aim of this study is evaluation of the resistant of the clinical strains Pseudomonas aeruginosa and Klebsiella pneumonia to common antibiotics and determining the common antibiotics and degree of increase MIC such as imipeneme and ciprofloxacin against these bacteria.Materials and Methods: In this study, at first 50 samples of Pseudomonas aeruginosa and 50 samples of Klebsiella pneumonia from different clinical specimens such as wounds, ear discharge, eye discharge, about patients in the ICU and CCU at hospitals were taken from each sample to identify the exact genus and species of bacteria, was in fully aseptic conditions on this Mac Kancky agar culture medium for growth of Klebsiella pneumonia and Strimid agar for Pseudomonas with four regional basis. After mass culturing purified colonies, separating and specifying Pseudomonas strain with biochemical methods. Then, in order to specify the anti microbial sensitivity of the considered antibiotics, created no growth halo on the plate were measured in millimeter.Results: The Analysis on bacterial resistance of Pseudomonas aeruginosa in Rifampin with rate (0.5 mg/L) showed that there is decrease on halo of growth around the antibiotic Rifampin disks also has been reported significant in overall E. coli strains at the lower level and on a higher level of resistance in Klebsiella pneumonia, while about the Tetracycline and Chloramphenicol and Ceftazidime antibiotics has not been reported these resistance.Conclusion: It was considered that Pseudomonas aeruginosa strains showed resistance to Rifampin in thicker halos and Klebsiella pneumonia strains showed resistance to Tetracycline in thinner ones, as well.