VAAM-Jahrestagung 2011 Karlsruhe, 3.–6. April 2011

OTP001Plasmid Profile and characteristics of Extended-spectrumBeta-lactamases Enzymes in Pseudomonas aeruginosaisolated from Intensive Care Units of Tabriz by PCRY. Hashemi Aghdam* 1 , H. Mobaiyen 2 , M. Beheshti 3 , M. Taghizadieh 4 ,S. Rahimi 5 , A. Moradi 61 Young Researchers Club, Tabriz Branch, Islamic Azad University, Iran2 Associated Professor of Microbiology Department, Medical Faculty,Islamic Azad University, Tabriz branch, Iran3 Associated Professor of Surgery, Medical Faculty, Islamic Azad University,Tabriz branch, Iran4 Assistant Professor of Pathology, Medical Faculty, Islamic AzadUniversity, Tabriz branch, Iran5 Medical Student, Medical Faculty, Islamic Azad University, Tabriz branch,Iran6 Associated Professor of Orthopedics Department, Tabriz University ofMedical Sciences, Tabriz, IranIntroduction: Antimicrobial resistance in hospital pathogens is animportant concern. Pseudomonas aeruginosa is one of the most commonagents in nosocomial infection. Infections caused by bacteria producingextended spectrum beta lactamases enzyme (ESBLs) can enhance it, so theycould be plasmid mediated resistant against beta- lactams. This study wasconducted to assay ESBL-producing strains of Pseudomonas aeruginosa.Methods: Samples from tracheal aspirate, urine, blood, bronchial aspirate,sputum, CSF, wound discharge, bone marrow and peritoneal fluid of thepatients of 5 hospitals in Tabriz were taken. All of isolates were identifiedusing conventional bacteriologic methods. They were tested forsusceptibility and screening of ESBL-producing by Disk diffusion methodand E-test, respectively. Plasmid DNA extraction was done by Kado and Liutechnique. The presences of bla CTX-M1, bla CTX-M2 were studied by PCR.Results: 240 ICU patients, infected by Gram-negative bacilli were studied.Pseudomonas aeruginosa was the second agents in nosocomial infection,64(26.6%). The susceptibility test showed 22%, 98%, 70% 100% and 100%resistance against Amikacin, Cephoxitin, ceftriaxone, Tetracycline andcefuroxime. The Double Disk Test showed 3.2%, 0% and 3.3% resistanceagainst Ceftriaxone, Cefotaxime, and Ceftazidime. The combined Testshowed 36.5% positive result against Cefotaxime / Clavulanic acid and32.5% against Ceftazidime / Clavulanic acid. By E-test 83.6 % of strainswere ESBL-producing. 64.5 % of isolates harbored a single plasmid of63kb. All of strains lacked either CTX-M-1 or CTX-M-2 gene to confirmthe rule for bla CTX-M.Conclusion: Pesudomonas aeruginsa was one of the most prevalentbacteria. Highest and lowest rate of resistance was showed againstCefuroxime, Tetracycline and Amikacin. Our results showed that DDT testwas not as sensitive as CT and MIC methods and no statistical significantdifference was found between results of CT and MIC. Confirming no rulesfor suspicious genes by PCR, 78% of strains were founded as ESBLproducer. Since the genes encoding theses enzymes are mainly located onplasmids, so transmission of the plasmids could disseminate the resistance infuture, unless the consumption of cephalosporins are restricted andantibiotics such as imipenem substituded for the third generationcephalosporins, because these antibiotics, especially ceftazidim andceftriaxone are strong inducers of ESBLs.[1] Kôseoglu. O, International of Antimicrobial Agents, 17: 477-481.[2] Ambrose PG, Crit Care Clin, 14: 283-308.[3] Helfand MS, Curr Drug Targets Infect Discord, 3: 9-23.[4] Shah A.A, Available online 16 March 2004. www.sciencedirect.com.[5] Medeiros AA. Clin Infect Dis, 24, S19-45.[6] Rupp ME, Drugs, 63: 353-365.[7] NCCLS. Document M100-S13.NCCLS, Wayne, Pensylvania, 2003.1.OTP002Diversity of Epiphytic and Endophytic Microorganismsin some dominant weedsI. Mukhtar*, I. khokhar, A. Ali, S. mushtaqInstitute of Plant Pathology, University of the Punjan, Lahore, PakistanA through study was conducted in May 2010 to assess the diversity in epiandendophytic microorganisms from the local weeds. In the search ofdiversity and relationship of epi and edophytic microorganism, 46 fungalstrains and 19 bacterial strains were isolated from the surface and the innertissue of four dominant agricultural weeds. A combination of culturalmethods i.e. Leaf wash and from homogenized leaf mixture solutionrespectively were used for the isolations from healthy leaves of four weedsviz. Chenopodium album, Euphorbia helioscopia, Partheniumhysterophorus, Convolvulus arvensis. Current study indicated that complexinteractions existed between the host and their epi and endophyticmicroflora. Each weed has specific bacterial community with the referenceof epi and endo phyllospere. The number and species of bacterial strainsvaried not only with their host weed plants but also in epi and endophyllospere. Sørensen's QS of all tested weeds for the endophytic andepiphytic bacterial assemblages was 0.00 that indicated no species overlap/similarity between the communities. Five fungal genera were common as epiand endophytes in all weeds samples: Aspergillus (56% of all isolates),Drechslera (10%), Alternaria (10%) Penicillium (6%) and Cladosporium(4%). Frequency of all five common genera differed significantly amongweeds. It was also noted that entophytic fungal communities were notnoticeably less speciose than epiphyte communities. Sørensen's QS ofEuphobia sp. (0.23), Chenopodia sp. (0.37) and Convolvulus sp. (0.46) forthe endophytic and epiphytic fungal assemblages was intermediate in therange (0.12-0.79) of previous studies. Although in case of P. hystophorus,the value for Sørensen's QS was 0.00 means no species similarity. The otheridentified genera were rare, such as Absidia, Cuvularia, Phoma andTrichoderma.OTP003Structure and molecular dynamics studies of the humananti-bacterial Dermcidin-channel (DCD)K. Zeth*Computational Biomolecular Dynamics, Max Planck Institute forBiophysical Chemistry, Goettingen, GermanyHuman DCD is produced in sweat glands and secreted to the surface of theskin in order to protect humans from bacteria such as Staphylococcus aureusand others. The small 48 residues long peptide has been synthesized andcrystallized in the presence of Zinc. The 3D architecture of the channel insolution is formed by six elongated, a-helical peptides with a strong chargedistribution inside the channel and small hydrophobic residues pointingoutwards (A,V,L). The internal symmetry is C3 due to the formation of thehexamer from a trimer of anti-parallel monomers. Six Zn-ions are bound atthe ends inside the channel, three at each end, stabilizing two peptides intheir anti-parallel arrangement. The length of the channel is 8 nm andslightly extends the diameter of a standard membrane. In moleculardynamics simulations, we observed that the channel adopts a tiltedorientation in membranes to minimize the hydrophobic mismatch. Using ournewly developed computational electrophysiology scheme, a conductance inthe range of ~10 pS is predicted together with cation selectivity. Also, weobserved unique ion entry and transfer mechanisms.OTP004The case of botulinum toxin in milk - experimental dataO.G. Weingart* 1,2 , T. Schreiber 3 , C. Mascher 3 , D. Pauly 3 , M.B. Dorner 3 ,T.F. Berger 4 , C. Egger 4 , F. Gessler 5 , M.J. Loessner 1 , M.-A. Avondet 2 ,B.B. Dorner 31 ETH Zurich, Institute for Food Nutrition and Health (IFNH), Zurich,Switzerland2 SPIEZ LABORATORY, Toxinology Group, Spiez, Switzerland3 Center for Biological Security, Robert-Koch-Institut, Berlin, Germany4 Agroscope Liebefeld-Posieux Research Station, Safety and Quality, Bern,Switzerland5 Miprolab GmbH, Göttingen, GermanyBotulinum neurotoxin (BoNT) is the most toxic substance known to manand the causative agent of botulism. Due to its high toxicity and theavailability of the producing organism Clostridium botulinum, BoNT isregarded as a potential biological warfare agent. Because of the mildpasteurization process, as well as rapid product distribution andconsumption, the milk supply chain has long been considered a potentialtarget of a bioterrorist attack. Since no empirical data on the inactivation ofBoNT in milk during pasteurization, to our knowledge, are available at thepresent time, we investigated the activity of BoNT/A and BoNT/B as well astheir respective complexes during a laboratory-scale pasteurization process.When we monitored milk alkaline phosphatase activity, which is an industryaccepted parameter of successfully completed pasteurization, our methodproved comparable to the industrial process. After heating raw milk spikedwith set amounts of BoNT/A, BoNT/B or their respective complexes, thestructural integrity of the toxin was determined by ELISA and its functionalactivity by mouse bioassay. We demonstrated that standard pasteurization at72°C for 15 seconds inactivates at least 99.99% of BoNT/A and BoNT/B,spektrum | Tagungsband 2011