فصلنامه زیست فناوری میکروبی
پیاپی 1 (تابستان 1388)

Malaria is one of the most important health problems in tropical countries. The main purpose of this study was to compare microscopically and PCR-RFLP methods for diagnosis of plasmodium parasites in dubious patients. We collected 102 blood samples which 77 of them are from patients referred to Bandar Abbas hospital and 25 of them are from healthy persons which used as control group. Slide thick and thin smears were prepared and observed by microscope. Blood DNA was extract and PCR reaction was performed. By using microscope methods, 35 % of samples were positive hence 75.2 % of them were PCR positive. In this study none of the samples which were reported positive by using microscope methods, were negative in PCR. For differentiation of plasmodium parasites RFLP was used which there were 12.96% P. malariae, 14.8% p. falciparum, 20.7% p.vivax, and 42.69% mix of plasmodium spp were observed. PCR method is more sensitive than microscopically methods for malaria parasites detection

Hepatitis B virus (HBV) belongs to hepadnaviridea family which is one of the main factors of hepatocellular carcinoma and liver diseases. The HBV detection methods (serological and molecular) have their own limitations, so the using ability of them in all diagnosis centres is not possible. In this study it has been tried to apply new novel LAMP technique on serum samples by using specific primer designed for HBs region. 104 HBV quantities sera by COBAS Amplicor Monitor kit were supplied. DNA was extracted by DNP kit and then PCR primers were selected and 6 specific primers were designed for LAMP. PCR and LAMP sensitivity and specificity were determined. PCR product by electrophoresis and LAMP product by adding 0.1% SYBR Green were identified. Among 104 quantitative serum, only 95 cases were PCR positive but 101 cases were LAMP positive.9 cases were PCR negative among these, 6 cases were reported as LAMP positive. In 3 cases LAMP and PCR were both negative. Application compression of PCR and LAMP technique on patient's samples with definite virus particles showed that the LAMP technique had more specificity and sensitivity.

water is considered as the most important factor or energy supply, thus providing safe water for drinking is a challenge for most countries as a result of increasing population and industrialization. The bacterium Escherichia coli is still the most important indicator for water pollution monitoring. The goal of this study is to evaluate membrane filtration (MF) method for the isolation and enumeration of E.coli in drinking water. 150 samples of mineral water bottles of different brands were tested in random for the detection of E.coli by membrane filtration method. All the tested samples were negative for fecal and total Coli forms, while 2% and 6% of samples were positive for other two indicators Enterococcus and Pseudomonas respectively. Our results confirm that the membrane filtration method is a suitable method for the detection of indicators in drinking water.

The Streptomycetes are gram positive, no motile and filamentous bacteria. Streptomyces is the largest antibiotic-producing genus in the microbial world discovered so far. In this research our goal is isolation Streptomycetes with antibacterial activity from some regions of North West of Iran including Tabriz, marand, khoy, maku in varius season of the year. The 100 soil samples were collected from mentioned regions in various seasons of the year. 150 different Actinomycetes isolates were obtained. These isolates extensively studied for their in vitro anti-microbial activity against Gram-positive and Gram-negative bacteria through two steps: primary screening, secondary screening. Twenty isolates showed a strong activity against pathogen bacteria. The results indicated that obtained isolates with an inhibition zone of ≥ 10mm were highly resistant against Staphylococcus aureus, Escherichia coli, Proteus vulgaris. These isolates were identified as Actinomycetes. Morphological and biochemical tests were done for distinguishing of samples. The strains of Actinomycetes were determined following the directions given in the probabilistic identification matrix of Williams and Bergey`s Manual of Systematic Bacteriology. Results obtained from the biochemical analyses including determination of 18 characteristics proved that 8 of strains were in similar group whereas three strains and one strain differed among each other. First group was determined as Streptomyces family with different species. Our studies showed that soil samples of Azarbaijan regions of Iran have an Actinomycetes diversity.

The bifunctional proline utilization A (PutA) contains proline dehydrogenase and ∆-pyrroline-5-carboxylate dehydrogenase domains and plays an important role in the metabolic pathway of proline to glutamate. The aim of this research was to isolate and identify the PutA falvoenzyme producing bacteria with appropriate kinetic properties. Needed soil samples were collected from different places of Tehran city including Darakeh, Darband, Farahzad and Damavand. Isolation and screening of falvoenzyme producing microorganisms was performed by enrichment culture technique in proline specific culture medium and enzyme activity staining by formazan color, reaction and confirmed by enzyme assay. Isolated strain was identified by phenotypic and biochemical characteristics. specific activity of falvoenzyme was also measured. In total of 400 isolated bacteria, only one of them was PutA producer that recognized as Pseudomonas fluorescens. The specific activity of falvoenzyme for L-proline and ∆1-Pyrroline-5-carboxylate was determined 22.4 U/mg and 10.7 U/mg, respectively. Specific activity of this enzyme for proline and ∆-pyrroline-5-carboxylate in compression with various amount of falvoenzyme which isolated from other resources is acceptable.

HU protein is a histone like protein that is called HBsu in Bacillus subtilis and it is encoded by hbs gene. It seems that HU protein sequence on various strains of one species could be different. DNA of B. subtilis with ATCC 6633, 12711 and 6051 were extracted and hbs gene was investigated by PCR. PCR products were sequenced in B. subtilis ATCC 6633 one nucleotide differs from B. subtilis ATCC 23857 (as reference that there is its sequence in gene bank), but there is no change in codon, while in two other strains (ATCC 12711 and 6051) all of the nucleotides of their hbs genes are similar to B.subtilis ATCC 23857. Previous studies showed that several proteins with properties and structures highly homologous to HU proteins have been isolated from other bacteria that their hu gene sequences on various strains of one species were different, nevertheless in this study with respect to unavailability of B.subtilis having ATCC 23857, each of these bacteria strain can be used as references in further studies.

Coral reefs of the Persian Gulf are normally subject to extreme environmental conditions including high salinity and seasonal variation in temperature. Previous studies elsewhere have shown that some Symbiodinium taxa such as the clade D group may be more resistant to heat stress than others. This study is the first to use molecular techniques to identify the Symbiodinium of the Iranian coral reefs on the basis of clade identification.

Samples of eight coral species were collected at two different depths from the eastern part of Kish Island in the northern Persian Gulf. Partial 28S nuclear ribosomal (nr) DNA of Symbiodinium (D1/D2 domains) were amplified by Polymerase Chain Reaction (PCR). PCR products were analyzed using Single Strand Confirmation Polymorphism (SSCP) and the phylogenetic analyses of the LSU DNA sequences.

The results showed that there are at least two clades of Symbiodinium from Kish Island. Clade D was detected from 8 of the coral species while clade C was found in 2 of species only.

The dominance of clade D might be explained by high temperatures typical for the Persian Gulf.

Existing of fine clay in mines and small particles of copper have caused reduction in chemical and biologicalreactions of these source, also using them makes it impossible to used in mass leaching operation in hydrometallargy of copper. In this study colum bioleaching of minus 1 mm fraction size of agglomeration of column bioleaching operation were evaloated. A column bioleaching test of agglomerated ore was run for 105 days along with a negative control using thymol as bactericide. At this stage,about 77.5% of copper was recovered while this amount in non-inoculated column was only 57%. The result showed that this procedure can be successfully used to obtain biologic copper in these resources.