MOSP - Macao Scientific Publishers

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The role of hp1165 gene on the efflux-mediated resistance to tetracycline in clinical isolates of Helicobacter pylori

T. Falsafi*, M. Anoushiravani and V. Niknam

Abstract: Tetracycline-resistant (TetR) Helicobacter pylori isolates have emerged in many parts of the world. We have previously demonstrated that among the mechanisms involved in the resistance of H. Pylori to Tet, its active efflux may be an important mechanism. This work, aimed to determine whether presence and/or expression of hp1165 are associated with efflux-mediated resistance to Tet in clinical strains of H. pylori. Twenty five TetR strains including seven low level-resistant, eight intermediately- resistant, and ten high-level resistant strains/or mutants, of which 21 displayed the active efflux ability for Tet, were investigated. They were screened for the presence of mutation (s) in 16S rRNA at 965- 967 position and for the presence of hp1165 gene. Detection of hp1165 gene transcription /or gene expression was performed by RT-PCR Two low-level Tet R strains displaying no efflux ability, that contained mutation (s) at 965-967 position of 16S rRNA. Ten out of 21 TetR strains displaying active efflux abilities, that contained hp1165 gene. Their PCR product was similar to that of 26695 standard strains, susceptible to Tet. RT -PCR was positive for five out of them however; their product size was approximately 100 bps smaller than that of 26695 strains. Regarding to the results of PCR and RT- PCR, hp1165 plays a role in the active efflux of Tet in resistant strains. A post-transcriptional regulation step may be involved in the expression of hp1165 gene in TetR strains.[...] Read More.

Keywords: Helicobacter pylori, tetracycline, resistance, efflux, hp1165 gene.

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Molecular and biochemical characterization of surfactin producing Bacillus species antagonistic to Colletotrichum falcatum Went causing sugarcane red rot

Muhammad Nadeem Hassan, A. Mark Osborn and Fauzia Yusuf Hafeez,*

Abstract: Bacillus species suppress phytopathogens by producing lipopeptide antibiotics, hydrolytic enzymes, siderophores and other secondary metabolites. Three bacterial strains Bacillus subtilis NH-100 (EU627167), B. subtilis NH-160 (EU627169) and Bacillus sp. NH-217 (EU627170) with proven ability to suppress red rot disease on sugarcane plants were further characterized to elucidate the multiple modes of action involved in their biocontrol activity. Plate assays pointed out the production of protease and antibiotics. Lipopeptide antibiotic surfactin was detected in the culture extract of B. subtilis NH-160 and Bacillus sp. NH-217 through LC-MS (Liquid chromatography - mass spectrometry). These results were further supported by identifying the presence of sfp and srfAC genes of surfactin biosynthetic operon using specific polymerase chain reaction (PCR) primers. Two strains B. subtilis NH-160 and Bacillus sp. NH-217 were further analyzed for their survival in compost which successfully retained consistency in their population 4.0 - 5.0 log CFUg-1 after 14th day. Bacteria capable of suppressing pathogens and maintaining their population by competing with other microbes can be successfully utilized as biopesticide for sustainable organic farming.[...] Read More.

Keywords: Bacillus, biocontrol, surfactin, sugarcane, red rot.

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In vitro antimicrobial activity of leaves of Acalypha indica Linn. (Euphorbiaceae)

M. N. Somchit,*, R. Abdul Rashid, A. Abdullah, A. Zuraini, Z. A. Zakaria, M. R. Sulaiman, A. K. Arifah and A. R. Mutalib

Abstract: The antimicrobial activity of water, ethanol and chloroform extracts of Acalypha indica was tested against four bacterial and fungal strains using the disc diffusion method. The antibacterial activity against gram positive bacteria was more pronounced (p < 0.05) in water and ethanol extracts. Antifungal activity was more significant (p < 0.05) only in chloroform extract. This antimicrobial activity was compared to standard antibiotics (penicillin, enrofloxacin, ampicillin and chlorampenicol) and antifungal drugs (ketoconazole, itraconazole and fluconazole). Findings from current study support the use of Acalypha indica in traditional medicine for the treatment of various bacterial and fungal infections.[...] Read More.

Keywords: Antifungal, antibacterial, disc diffusion assay.

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Identification of Streptococcus salivarius bacteriophage isolated from Persian Gulf as a potential agent for dental caries phage therapy

Keivan Beheshti Maal, Majid Bouzari* and Farahnaz Arbabzadeh Zavareh

Abstract: The aim of this research was to detect oral Streprtococci bacteriophages from Persian Gulf. Dental plaque samples were collected using sterile explorer and cultured in brain heart infusion (BHI) Broth. The oral Streptococci were isolated in culture media. The Persian Gulf water sample was gathered using a sterile bottle from the depth of 50 cm under the inframarine surface at Boushehr Port, Boushehr state, Iran. The Persian Gulf water was centrifuged and its supernatant was filtered through a 0.45 micrometers membrane filter and with a sterile Millipore filtration system. The filtrates were added to activate oral Streptococci at their logarithmic phase and cultured in (BHI) Agar using overlay method. Bacteriophage plaque forming assay in (BHI) Agar and clearance of (BHI) Broth suggested the presence of specific bacteriophages in sample. Transmission electron microscopy revealed that the capsid of the isolated bacteriophage was hexagonal (diameter: ~ 83.33 nm) most probably related to Cystoviridae family. This is the first report of isolation and identification of oral Streptococci bacteriophages from Persian Gulf located in South of Iran. The applications of these lytic phages as a potential for phage therapy of dental plaque could be considered as the significance and impact of the present study.[...] Read More.

Keywords: Persian Gulf, Streptococcus salivarius, bacteriophages, phage therapy, dental plaque, pharmaceutical and medical biotechnology.

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Textile effluent treatment by Bacillus species isolated from processed food

N.Murugalatha*, A. Mohankumar, A. Sankaravadivoo and C. Rajesh

Abstract: Colour removal of industrial effluent has been a major concern in waste water treatment, especially for the waste water that originates from textile and dye stuff plant with a continuous discharge of great quantity of remaining dyes to the environment. The efficient treatment of the effluent is an eco- friendly method for the treatment of textile effluent. Bacillus species was isolated from the processed food-pickles and were characterized by means of biochemical reactions. Spore formers, non spore formers and their supernatant were used for the treatment. Effluent collected from the textile was diluted to 10, 50 and 90%, were subjected to biological treatment. The level of degradation rate was increased to 87.7 to 93.3% on dilution at 50 and 90% respectively when spore formers were used. The culture supernatant was able to degrade the dye at a rate of 34% with crude effluent and 98 with 90% of diluted effluent. Probably the metabolites produced by the organism were involved in the dye degradation process.[...] Read More.

Keywords: Textile effluent, Bacillus species, declorization, aerobic degradation.

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Serological and bacteriological study of leptospirosis in slaughtered cattle in north of Iran (Rasht)

T. Shafighi, G. Abdollahpour*, T. Zahraei Salehi and H. Tadjbakhsh

Abstract: A serological and bacteriological study was performed in Guilan industrial slaughter house, in Rasht, North of Iran in 2009. To investigate the seroprevalence of leptospirosis in slaughtered cattle in Guilan, 59 and 39 random serum samples were collected from cows and bulls, respectively. None of the cattles was vaccinated against leptospirosis. Also urine samples were collected from all of the blood-sampled cattle and cultured. All serum samples were serologically tested by microscopic agglutination test (MAT), as a standard method for serological diagnosis of leptospirosis. The serum samples were tested for antibodies against eight live antigens of Leptospira interrogans serovars: Australis, Autumnalis, Canicola, Grippotyphosa, Hardjo, Icterohaemorrhagiae, Pomona and Sejroe. The lowest dilution that each serum was considered positive was 1:100. The results of this study showed that 37 (37.8%) animals had a positive reaction against one or more serovars. The most prevalent Leptospira serovars was Pomona (49.0%). One leptospiral organism was isolated from 98 urine samples of cows and bulls. The results of this study indicates that leptospiral infection is magnified in cattle in Rasht, and cattle have a major role in maintaining Pomona serovar; indeed they are a potential zoonotic risk to slaughter house workers, meat inspectors, milkers and farmers.[...] Read More.

Keywords: Iran, Rasht, serology, bacteriology, cattle, leptospirosis.

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Campylobacteriosis in sheep in farm settlements in the Vhembe district of South Africa

Uaboi-Egbenni, P. O., Bessong, P. O., Samie, A. and Obi, C. L.

Abstract: A total of 300 freshly voided sheep faeces were collected and screened for the presence of Campylobacter spp. using standard microbiological techniques. The samples were obtained randomly from 3 farm settlements in the Venda Region, South Africa in 2008 and 2009. The recovery rate was 30.0% (90 of 300) for all faeces. Of these, 65 (72.2%) were from diarrheic and 25 (27.8%) were from non-diarrheic faeces. Out of the 90 Campylobacter spp. isolated, 41(45.6%) were Campylobacter jejuni and 49 (54.4%) were C. coli. Sixty-three (70%) of the isolates were -haemolytic, while 17 (18.9%) were - haemolytic and 10 (11.1%) were non-haemolytic on 5% sheep red blood cells. The antibiotic resistance patterns of the 90 Campylobacter isolates were examined by the disc diffusion method. All Campylobacter isolates from the farms were resistant to at least one of the 12 antibiotics tested. The prevalence rate of C. coli resistance to ciprofloxacin was 20.4% compared with C. jejuni, 17.1%. Similar rates were noted for tetracycline for the two species. C. jejuni showed a higher rate of resistance to erythromycin (22.0%) compared with Campylobacter coli (10.2%). Significantly higher frequency of kanamycin resistance was recorded for C. jejuni compared to C. coli (p < 0.005). However, for ciprofloxacin, tetracycline, erythromycin, imipenem, gentamycin and ampicillin comparable resistant profiles were recorded for C. jejuni and C. coli isolates from the farms. The high prevalence of Campylobacter spp. in sheep is of public significance in the Venda Region. The observed multi-drug resistance and especially resistance to macrolides and fluoroquinolones in this study pose a threat of transfer of antibiotic resistance to human pathogens because of the close contact between sheep and humans.[...] Read More.

Keywords: Antibiotics, Campylobacter, haemolytic, macrolides, pathogens, resistance.

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Bio-nanomodeling of active site in oxidized azurin using by computational methods

F. Mollaamin*, K. Shahani poor, T. Nejadsattari and M. Monajjemi,

Abstract: A cluster model for active site of oxidized azurin was presented and investigated the geometric structure and thermochemical parameters. Quantum-mechanical calculations were performed at the HF and B3lYP/6-31G levels of theory in the gas phase and eight solvents at four temperatures. Also, nuclear shielding parameters of the active site of oxidized azurin have been taken into account using GIAO and CSGT methods at the HF and B3LYP/6-31G levels of theory in the gas phase and in different solvents such as water, DMSO, nitromethane, methanol, ethanol, acetone, dichloroethane and dichloromethane. The results were revealed that the NMR chemical shielding parameters are strongly affected by inducing different solvent media. According to these theoretical results of energy values, some important relationships have been found between the dielectric constant and structural stability of active site of oxidized azurin. Thus, it can be drastically concluded that the dielectric permittivity of the solvent is a key factor that determines the chemical behavior of active site azurin in solution.[...] Read More.

Keywords: Azurin, IR, nuclear magnetic resonance, blue copper proteins, solvent effect.

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Does dermatophagoides cause different allergic rhinitis clinic than pollens?

M. Akarcay*, M. C. Miman, O. Miman, M. Kelles and N. Ekici

Abstract: The aim of this study was to compare allergic rhinitis clinics caused by two most common allergens: house dust mites (HDM) and pollens. Three hundred and fifty patients were evaluated. These patients were pure pollen or HDM allergic according to skin prick test (51 HDM+, 299 Pollen+). Mainly, HDM were allergens for perennial allergic rhinitis, while pollens were for seasonal allergic rhinitis (p < 0.01). Both groups were found with similar symptom frequency except palatal, ocular, throat itching and eye redness indicating mostly pollen allergy (p < 0.05). Seasonal exacerbations used for the differential diagnosis were found to be very significantly different. Spring and autumn were the seasons where pollen allergy symptom exacerbation was mainly seen (p < 0.01) . HDM allergy was uniquely found with symptom exacerbations in winter (p < 0.05). Rural area visit was found dominating triggering factor for pollen allergy (p < 0.05). The most common triggering factor was house dust exposure in HDM+ group (p < 0.05). HDM allergy being mostly mimicking pollen allergy in allergic rhinitis, however, differs from it with some clinical features. This could be detected with detailed history taken from the allergic rhinitis patients. While doing definitive diagnosis, prick test may be helpful with a clear patient history in patients hard to diagnose.[...] Read More.

Keywords: Mite, pollen, allergy, rhinitis.

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Survival enhancement of probiotic Lactobacillus plantarum CMU-FP002 by granulation and encapsulation techniques

Sasimar Woraharn, Chaiyavat Chaiyasut*, Busabun Sirithunyalug and Jakkapan Sirithunyalug

Abstract: Two processes of enclosure of probiotic Lactobacillus plantarum CMU-FP002, probiotic granules and calcium alginate beads, were studied. Sodium alginate solution at 1.0, 1.5 and 2.0 % (w/v) was used as a binder. The results showed that 20 log cfu/ml initial concentration of cells could be entrapped by the granules and beads with 12 to 13 log cfu/g and 16 cfu/g, respectively. The physical properties of granules and beads revealed that the strength increased when sodium alginate concentration was increased. On the other hand, the dissolution decreased. Probiotic granules completely released the cells within 60 min after being suspended in stimulate gastric fluid (SGF) pH 1.8 and had 2 to 3 log survival cells per gram. Calcium alginate beads, which were formulated from 1.0 and 1.5% (w/v) sodium alginate solution, gradually released bacterial cells and were completely released in SGF within 120 min. The beads formulated from 2.0 %(w/v) sodium alginate solution could not completely release the probiotics. The beads contained more survival cells than granules. Furthermore, the beads formulated from 1.5% (w/v) sodium alginate solution had the highest survival cells (9.30 log cfu/g). Probiotic cells in calcium alginate beads were still high (11 log cfu/g), although they were stored at 4˚C for 5 days alternating with room temperature for 5 days, for a total of 2 month. Further application in broilers will be studied.[...] Read More.

Keywords: Probiotic, survival enhancement, granulation, encapsulation, Lactobacillus plantarum.

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