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Introduction. The main aetiological agent of urinary tract infection (UTI) is Escherichia coli , categorized as uropathogenic E. coli (UPEC). The genome of UPEC shows a high degree of plasticity, which leads to the emergence of ‘intermediary strains’ with different traits from the parental pathotypes. Gap Statement/Aim. We aimed to assess the frequency and types of the hybrid UPEC among isolates causing UTI and characterize virulence properties of these hybrid isolates molecularly and phenotypically. Methodology. After detection of intestinal pathogenic E. coli (IPEC) virulence markers among 200 UPEC isolates, they were assessed for the presence of 40 virulence genes (VGs) of extraintestinal, uropathogenic and diarrhoeagenic E. coli , phylogenetic group typing, phenotypic traits including biofilm formation, adherence and invasion to HeLa cells, haemolysis activity and antimicrobial resistance. Results. The analysis showed 21 (10.5 %) UPEC isolates carried enteroaggregative E. coli (EAEC) and enteropathogenic E. coli (EPEC) virulence markers. Twenty isolates carried the aggR (EAEC) and one the eae and escV genes (EPEC), which were classified as hybrid strains. The most commonly identified genes were fimH (71.5 %), fyuA (66.7 %), iutA (62 %), chuA (57.1) and traT (47.6 %). Biofilm production, adhesion and invasion were found among 17 (81), 18 (85.7) and 11 (52.4 %) hybrids, respectively. Investigation of the genetic characteristics, phylogenetic group and virulence profile of the detected hybrids revealed that they have genetic diversity and do not belong to a particular clonal lineage. Conclusion. The present study reveals that some UPEC may carry virulence markers of IPEC pathotypes. EAEC and EPEC seem to have a greater tendency to form hybrids and cause UTI. Further studies are needed to elucidate what factors contributed to survival in the urinary tract system and facilitate infection and whether these combinations lead to an increase in pathogenicity or not.

Methyl tertiary butyl ether (MTBE) is a high soluble oxygenated supplement to fuel that may rapidly contaminate water and soil. Low biodegradability of this compound in the environment has led to m...

Many efforts have been made around the world to combat SARS-CoV-2. Among these are recombinant antibodies considered to be suitable as an alternative for some diagnostics/therapeutics. Based on their importance, this study aimed to investigate the expression, purification, and efficiency of a new potent recombinant scFv in the E. coli BL21 (DE3) system. The expression studies were performed after confirming the scFv cloning into the pET28a vector using specific PCRs. After comprehensive expression studies, a suitable strategy was adopted to extract and purify periplasmic proteins using Ni

Background: Due to their high amount of carbohydrate and enough moisture, cereals are a good environment for the growth of toxigenic fungi. Because of the carcinogenicity and mutagenicity of mycotoxins, preventing them from entering the food chain is essential. Therefore, the present study was conducted to determine the amount and type of contaminated imported cereals and rice produced in Khuzestan province Materials & Methods: In October and November 2015, a total of 50 random samples of rice was collected from paddy fields. Aspergillus were identified based on available diagnostic criteria and PCR. The amount and type of aflatoxin in rice samples and mycotoxins in imported cereals (winter 2015 to autumn 2016) were evaluated by HPLC Result: Based on one sample t-test and comparing the mean of mycotoxins contaminating cereals in different seasons with national maximum standard, the amount of mycotoxins in barley and wheat were within the standard range but %8.4 of corn was higher than the permitted level (ppb5). Analysis of aflatoxins in rice also showed that 16 samples were contaminated with aflatoxin B1. Aspergillus flavus was the major pollutant (%42.1) isolated from rice. Conclusion: Aspergillus flavus is the major producer of aflatoxin B1 in domestic rice. Examination of imported cereals also showed high rates of fungal growth and production of secondary metabolites, possibly due to inadequate storage conditions, high temperature and humidity. Therefore, it is recommended to strengthen the monitoring tools in the processing and storage of rice and cereals.

Aim: We aim to use peptide nucleic acid (PNA) for antisense therapy against bovine viral diarrhea virus (BVDV), a surrogate model of human hepatitis C virus, and introduce an optimal approach for delivering PNA into the cell. Materials & methods: PNA was designed for hybridization to the 5′-untranslated region of BVDV RNA in order to form a heteroduplex structure and inhibit the translation and replication of virus. Gold nanoparticles (AuNPs) were used as a delivery system for PNA. Results: The cellular uptake of PNA-AuNPs and inhibition of BVDV infection in the middle stage of viral replication were found. Conclusion: Further research is warranted to develop AuNPs as a potential vehicle for delivering PNA in order to remove viruses from the infected cells.

The oil spills in the vicinity of the Garo sulfidic springs in Golgir region, MIS oilfield, Iran, were investigated for halotolerant/halophilic microorganisms capable of crude oil biodegradation. Screenings resulted in an isolate capable of growth on crude oil of the local Asmari reservoir in media containing 30–100 g/L NaCl at 28 °C. The isolate, designed as KWPA-12, was an aerobic, motile, oxidase and catalase positive, Gram-negative rod. It was shown that strain KWPA-12 can utilize crude oil as the carbon and sulfur sources with a significant efficiency. The Asmari crude oil biodegradation in 90 g/L NaCl containing media was investigated by turbidity measurement, GC-FID and TPH analyses. The results showed that the aliphatic hydrocarbons including: small C11–C12 and long chains: C31–C33, are mostly favored by strain KWPA-12. Anthracene: a tri-ring and one of the most dominant poly-aromatic compounds of Asmari crude oil, was reduced down to about 1.1% of the starting moiety. Phylogenetic investigations performed on the partial 16S rRNA gene sequence indicated that the strain belongs to the genus Halomonas and it fell into the Halomonas elongata clade.

Introduction: Diarrheagenic Escherichia coli (DEC) is a major etiologic agent among the pathogens that cause diarrhea in children. Methodology: To investigate the presence and pathotypes of DEC in children under five years of age, living in the province of Khouzestan, Iran. 208 diarrhea stool samples were screened by multiplex-PCR. The isolated DEC isolates were investigated for resistance to various antimicrobials including the production of extended-spectrum beta-lactamases (ESBLs) and phylogenetic groups were determined. Results: DEC isolates were identified in 54 (26%) diarrhea samples, and 4 (7%) cases contained two DEC pathotypes. DEC isolated included 35 (16.8%) enteroaggregative E. coli (EAEC), ten (4.8%) enteropathogenic E. coli (EPEC), six (2.9%) enteroinvasive E. coli (EIEC), six (2.9%) enterotoxigenic E. coli (ETEC) and one (0.48%) LEE-positive EAEC. Shiga-toxin producing E. coli (STEC) was not identified in any diarrheal samples. The most prevalent resistance was observed with ceftazidime (88%), followed by ceftizoxime (83%) and ceftriaxone (71%). The majority of isolates (> 75%) were sensitive to Imipenem, ciprofloxacin, and amikacin. More than 65% of the pathogenic isolates showed a multidrug-resistant phenotype. ESBL-producing strains was observed in 79.3% of all DEC isolates. Phylogenetic group B2 was the most predominant group with a frequency of 44.8%. A significant association was observed between the B2 phylogenetic group and the DEC isolates (P < 0.05). Conclusions: Overall, our findings highlight the importance of the role of DEC isolates in the etiology of diarrhea in children in Iran. The progressive increase in antimicrobial resistance among DEC isolates makes it imperative to implement policies to control the spread of resistant bacteria.

Foot-and-mouth disease (FMD) is an extremely contagious viral disease of cloven-hoofed animals that can lead to huge economic losses in the livestock production. No antiviral therapies are available for treating FMD virus (FMDV) infections in animals. The antiviral effects of magnesium oxide nanoparticles (MgO NPs) on the FMDV were investigated in cell culture. The viability of the cells after MgO NP treatment was determined using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. The direct effects of MgO NPs on the FMDV in extracellular (virucidal assay) and also different stages of virus replication (antiviral assay) were evaluated by plaque reduction assay. The results showed that MgO NPs were safe at concentrations up to 250 µg/ml in the Razi Bovine kidney cell line. The treatments with NPs indicated that the MgO NPs exerted in vitro virucidal and antiviral activities. Plaque reduction assay revealed that MgO NPs can inhibit FMDV by more than 90% at the early stages of infection such as attachment and penetration but not after penetration. The results of this study suggested that NPs might be applied locally as an antiviral agent in early stages of infection in susceptible animals.

The rotavirus is one of the major factors of inducing the acute gastroenteritis infection in children under 5 years of age. The laboratory diagnosis is progress and bringing it under control as well as avoiding its diffusion. The purpose of the present study was to determine the performance of enzyme linked immunosorbent assay (ELISA) and Latex agglutination (LA) tests against reverse transcription-polymerase chain reaction (RT-PCR) for evaluating the children’s acute gastroenteritis by rotavirus. One hundred feces specimens were collected from February to May 2014 and analyzed by LA, ELISA and RT-PCR. In this study, the positive results for rotavirus detected by ELISA, LA and RT-PCR were 37, 43 and 27%, respectively. In addition, the result showed that the sensitivity and specificity of ELISA and LA were 74 and 85%, respectively, when compared to RT-PCR. For laboratory detection of Rotavirus infection, RT-PCR has the highest sensitivity and specificity but because of the high costs, ELISA and LA based kits with good performance, as shown by this study, can be preferred for the routine use.

Ligninolytic enzyme complexes are involved in lignin degradation. Among them laccases are outstanding because they use molecular oxygen as a co-substrate instead of hydrogen peroxide as used by peroxidases. Bacterial laccase of Bacillus genus was first reported in Claus and Filip (Microbiol Res 152:209–216, 1997), since then more bacterial laccases have been found. In this research, laccase-producing bacteria were screened from pulp and paper industry wastewater, bagass and sugarcane rhizosphere. Nutrient agar medium containing 0.5 mM of guaiacol was used. It was observed that the laccase-producing strains developed brown colour from which 16 strains of Bacillus were identified. One of the isolated strains was identified as Bacillus subtilis WPI based on the results of biochemical tests and 16S rDNA sequence analysis. This strain showed laccase-like activity towards the oxidizing substrates ABTS and guaiacol. In this study guaiacol was used as the substrate of laccase activity assay. For determination of laccase activity of this isolate guaiacol was used as a substrate of assay for the first time in this study. SDS-PAGE and Native-PAGE confirmed the presence of laccase.

The demand for recombinant proteins for therapeutic or diagnostic use is expanding rapidly in recent years. Human gamma interferon (Hu-IFN-γ) is one of these proteins against viruses that it has a high value in therapy Therefore interferon is used against viral infection, cancer and autoimmune diseases. In this study appropriate primers were designed and used for PCR amplification of the Hu-IFN-γ gene which was cloned in the plant expression vector pCAMBIA1304. The created construct was transferred in Agrobacterium tumefaciens strain LBA4404 and used for transformation of tomato cotyledon explants. The presence of the Hu-IFN-γ transgene in the genomic DNA of transgenic plants was proven by PCR. Finally, total protein of tomato was extracted and the presence of Hu-IFN-γ proteins was detected using dotblot assay.

The aim of this study was to isolation of marine antibiotic-producing bacteria from the Persian Gulf, as an untapped source for searching new natural drugs. Bioactivity of ethyl acetate extract prepared from marine bacterial isolates was evaluated against 21 human pathogenic bacteria. GCI (Growth Curve Interference) parameter was determined for the obtained marine antibiotic compound against MRSA (Methicillin resistant Staphylococcus aureus ). Finally, identification of intended isolate was done based on phenotipically and phylogenetically characters. Overall, 49 bacterial colonies were isolated but only one isolate from coastal sediment identified as Pseudoalteromonas piscicida PG-02 showed antibacterial activity. It was effective against all of tested bacteria except Listeria monocytogenes (clinical), L. monocytogenes (ATCC 19112), Proteus mirabilis (clinical) and Klebsiella pneumoniae (clinical). GCI parameter was obtained with concentration just near to MIC (GCI: 20 mg/mL). In conclusion, this marine bacterium can give hopes for treatment of diseases caused by multidrug resistant (MDR) bacteria.

Objective To investigate the isolation of marine antibiotic-producing bacteria from the Persian Gulf, as an untapped source for searching new natural antibiotics. Methods Initially water and sediment samples were collected from 18 study sites in the some northern areas of Persian Gulf. All of the bacterial isolates using Marine Agar 2216 were inoculated into Marine broth and incubated on a rotary shaker at 28 °C for 2-7 days. Bioactivity of their ethyl acetate extract was assessed at 100 mg/mL concentration in disc diffusion method against 6 gram-positive and 5 gram-negative bacteria. Synthetic antibiotics were used as control. Results Altogether, 46 bacterial colonies were isolated. Only one isolate from a marine sediment sample collected at a depth of 10 m, identified as Pseudomonas aeruginosa PG-01, was exhibited the capability of antibiotic production. The obtained raw extract from intended bacterium was effective against all tested gram positive bacteria while gram negative bacteria were resistance. Methicillin resisitant Stapuylococcus aureus (MRSA), Streptococcus pyogenes (S. pyogenes), Staphylococcus epidermidis ( S. epidermidis ) and Bacillus cereus ( B. cereus ) were the most sensitive strains. All of tested pathogens were multidrug resistant. The antibacterial compound from this bacterium was active even at 120 °C. The optimized temperature and time for antibacterial metabolite production were 37 °C and 72 hrs, respectively. Conclusions Considering the antibacterial effect of Pseudomonas aeruginosa PG-01 especially against MRSA, it can be regarded the intended bacterium as a valuable strain and can give hope for treatment of diseases caused by multidrug resistant bacteria.

Background: Foot and mouth disease (FMD) is an infectious disease of cloven-hoofed animals that has adverse economic impacts. Given the prevalence of this viral infection, the lack of effective treatments, and the presence of resistant strains, the progression of novel antiviral agents is needed. Objectives: The purpose of this study was to investigate the anti-FMDV activity of the methanolic extract of Alhagi maurorum Medik (camel thorn), via cell cultures. This study was done to evaluate the biologically active substances in extract of camel thorn and their applications in herbal and traditional medicine. Materials and Methods: Extraction of A. maurorum Medik was carried out in an 80% methanol solvent system. The maximum concentration of the extract with non-cytotoxic effects on cells was determined using an MTT (3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyl tetrazolium bromide)-assay. Then, this concentration was incubated with ten-fold serial dilutions of the virus. The antiviral activity of the tested compounds was evaluated by measuring the reduction in CPEs and calculating and comparing the TCID50, before and after treatment with the extract, via the Reed & Muench method. Results: The MTT assay revealed that methanolic extract in a concentration of 3 mg/mL or less has no cytotoxic impact, and the 50% cell cytotoxicity (CC50) was about 30 μg/mL. The Reed & Muench method showed that A. maurorum Medik has anti-FMDV activity and it can reduce the titer of the virus by at least 2 × 3.5 log. Conclusions: The present investigation supports the use of the methanolic extract of A. maurorum as an antiviral drug in folk and modern medicine. This activity may justify its use as a source of natural compounds to control FMDV in infected animals.

In this study, we evaluated the antiviral activity of gold nanoparticles (AuNPs) against the foot-and-mouth disease virus (FMDV), that causes a contagious disease in cloven-hoofed animals. The anti-FMDV activity of AuNPs was assessed using plaque reduction assay. MTT assay was used for quantitatively measuring the cytopathic effect caused by the viral infection. The 50% cytotoxicity concentration of nanoparticles was measured and found to be 10.4 $\mu$ g/ml. The virus yield reduction assay showed that AuNP have an approximately 4-fold virus titer reduction compared with controls. Plaque reduction assay showed that at non-cytotoxic concentrations, AuNPs do not show extracellular virucidal activity and inhibition of FMDV growth at the early stages of infection including attachment and penetration. Time-of-addition experiments revealed that AuNPs inhibited post-entry stages of viral replication concomitant with the onset of intracellular viral RNA synthesis; however, the mechanism of AuNPs against FMDV was unclear.

A novel desulfurizing bacterium has been isolated from oil-contaminated soils in Khuzestan. The ability for dibenzothiophene desulfurization and its biochemical pathway were investigated. The bacterium was identified as Gordonia sp. AHV-01 (Genbank Accession No HQ607780) by 16S rRNA gene sequencing. HPLC results and Gibb's assay were shown that dibenzothiophene desulfurized via 4S-pathway Maximum growth (0.426 g dry cells/L) and produced 2-hydroxybiphenyl (63.1 microM) were observed at 120 h of cultivation. By using of response surface design procedure the optimization of pH, temperature and rotary shaker round on the desulfurization reaction of isolate AHV-01 were performed. The optimum conditions were determined at pH of 7.0, temperature of 30 degrees C and rotary shaker round of 180 rpm. At these conditions, the dibenzothiophene desulfurization activity was increased and maximum 2-hydroxybiphenyl production was detected 70.29 microM at 96 h. According to these results, Isolate AHV-01 was capable to desulfurize dibenzothiophene via 4S-pathway and likely it can be useful to reduce organic sulfur contents of crude oil.

Nowadays, emergence and prevalence of MRSA (Methicillin Resistant Staphylococcus aureus) strain have become a great global concern in 21st century, so, it is necessary to discover new antibiotics against this pathogen. The aim of this study was isolation and evaluation marine bacteria from the Persian Gulf in order to finding antibiotic compounds against some pathogenic bacteria. For this purpose, water and sediment samples were collected from the Persian Gulf during March to October 2009. The antibacterial activity of the isolated bacteria was assessed using disc diffusion method. The Growth Curve Interference (GCI) parameter against MRSA was determined for the high potential antibiotic producing strain. The most important factors affecting fermentation conditions in antibiotic production were also optimized. Definite identification of intended isolate was confirmed by 16S rRNA sequencing. Altogether, 51 bacterial colony was isolated and among them only 3 bacterium showed antibacterial activity. Pseudoalteromonas piscicida PG-01 isolated from a sediment sample was chosen as the best antibiotic producing strain. This strain was effective against all tested Gram-positive bacteria, had good anti-MRSA activity and also GCI value against MRSA was two times lower than MIC value. Among the optimized fermentation parameters, carbon and nitrogen sources play major role in efficacy of optimized antibiotic production. Ultrastructural study on the effect of intended antibiotic compounds on MRSA using TEM revealed that the target site for this compound is cell wall. Considering the antibacterial effect of PG-01 strain especially against MRSA, intended antibiotic compounds can gives hope for treatment of diseases caused by multi-drug resistant bacteria.

To determine the prevalence of cervicalChlamydia trachomatisgenotypes in Iran for the first time and their association with three clinical symptoms/signs, i.e. abnormal vaginal discharge, lower abdominal pain (LAP) and swab-induced bleeding, and patient age, 620 cervical specimens were obtained from women with symptomatic genital infection referred to gynaecological clinics and 108C. trachomatis-positive specimens were genotyped by directomp1gene PCR-RFLP analysis. Eight genotypes were identified. The most prevalent genotype was E (31.5 %), followed by F (23.1 %), D/Da (13 %), K (9.2 %), I (8.3 %), G (7.5 %), H (5.5 %) and J (1.9 %). For analysing the association ofC. trachomatisgenotypes with symptoms/signs and age,P-values were separately evaluated for genogroups and genotypes. The analysis of genogroups showed that women infected with genogroup F/G manifested the symptom of LAP significantly more often than those infected with the other genogroups (P=0.02), while the analysis of genotypes revealed that women infected with genotype F reported LAP slightly more often than women infected with the other genotypes (P=0.08). No significant correlation between genogroups and age was found; however, genotype E was somewhat less prevalent among women aged 25–34 years than among other age groups (P=0.08).

Oil-polluted soils were sampled from National Iranian South Oil Company (NISOC) for isolation and screening of C–S and not C–C targeted Dibenzothiophene (DBT) degrading microorganisms. Microbacterium sp. NISOC-06, a C–S targeted DBT degrading bacterium, was selected and its desulfurization ability was studied in aqueous phase and water-gasoline biphasic systems. The 16srRNA gene was amplified using universal eubacteria-specific primers, PCR product was sequenced and the sequence of nearly 1,500 bp 16srDNA was studied. Based on Gas Chromatography results Microbacterium sp. NISOC-06 utilized 94.8% of 1 mM DBT during the 2 weeks of incubation. UV Spectrophotometry and biomass production measurements showed that the Microbacterium sp. NISOC-06 was not able to utilize DBT as a carbon source. There was no accumulation of phenolic compounds as Gibb’s assay showed. Biomass production in a biphasic system for which DBT-enriched gasoline was used as the sulfur source indicated the capability of Microbacterium sp. NISOC-06 to desulfurize gasoline.