Publications by authors named "Andreas Thomann"

27 Publications

  • Page 1 of 1

Complete Genome Sequence of Mycoplasma feriruminatoris Strain IVB14/OD_0535, Isolated from an Alpine Ibex in a Swiss Zoo.

Microbiol Resour Announc 2020 Mar 19;9(12). Epub 2020 Mar 19.

Institute of Veterinary Bacteriology, University of Bern, Bern, Switzerland

is a fast-growing and genetically tractable mycoplasma species. We sequenced the Swiss strain IVB14/OD_0535, isolated from an Alpine ibex. This strain has a circular genome of 1,027,435 bp with a G+C content of 24.3%. It encodes 835 open reading frames (ORFs), 2 rRNA operons, and 30 tRNAs.
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http://dx.doi.org/10.1128/MRA.01528-19DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7082462PMC
March 2020

An unusual case of bovine anthrax in the canton of Jura, Switzerland in 2017.

BMC Vet Res 2019 Jul 29;15(1):265. Epub 2019 Jul 29.

Institute of Veterinary Bacteriology, University of Bern, Bern, Switzerland.

Background: Anthrax caused by Bacillus anthracis is a zoonotic disease mainly affecting herbivores. The last Swiss outbreak was over 20 years ago. We describe a recent anthrax outbreak involving two cows from the same herd. One cow was designated as a peracute clinical case with sudden death and typical lung lesions, while the other cow presented with protracted fever and abortion.

Case Presentation: On April 29th 2017, a 3.5-year-old Montbéliard dairy cow was found dead while out at pasture with haemorrhage from the nose. The veterinarian suspected pneumonia and performed a necropsy on site. Subsequently, a lung and liver sample were sent to the laboratory. Unexpectedly, Bacillus anthracis was isolated, a pathogen not found in Switzerland for decades. Several days later, a second cow from the same farm showed signs of abortion after protracted fever. Since these symptoms are not typical for anthrax, and the bacteria could not be demonstrated in blood samples from this animal, a necropsy was performed under appropriate biosafety measures. Subsequently, Bacillus anthracis could be isolated from the placenta and the sublumbal lymph nodes but not from the blood, liver, spleen and kidney. The outbreak strain (17OD930) was shown to belong to the lineage B.Br.CNEVA, the same as Swiss strains from previous outbreaks in the region. We speculate that the disease came from a temporarily opened cave system that is connected to an old carcass burial site and was flushed by heavy rainfall preceding the outbreak.

Conclusion: Even in countries like Switzerland, where anthrax is very rare, new cases can occur after unusual weather conditions or ground disturbance. It is important for public officials to be aware of this risk to avoid possible spread.
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http://dx.doi.org/10.1186/s12917-019-1996-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6664520PMC
July 2019

Non-aureus Staphylococci Species in the Teat Canal and Milk in Four Commercial Swiss Dairy Herds.

Front Vet Sci 2019 12;6:186. Epub 2019 Jun 12.

Vetsuisse Faculty, Clinic for Ruminants, University of Bern, Bern, Switzerland.

Non-aureus staphylococci (NAS) are frequently found in milk samples as well as on the teat apex and in the teat canal and are known to be a cause of subclinical mastitis. The objective of this study was to investigate the relationship between NAS species colonizing the teat canal and those causing intramammary infection (IMI) in four commercial dairy herds. Teat canal swabs were obtained and thereafter milk samples were aseptically collected and evaluated for the presence of staphylococci using selective agar plates. Species identification was performed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The relationship between NAS species distribution and sample type (teat canal vs. milk samples) was quantified using hierarchical multivariable logistic regression models. The most prevalent NAS species in teat canal swabs were (35%), (10%), and (7%), whereas in milk samples (5%), (5%), and (4%) were most prevalent. There were significantly higher odds for (OR = 215), (OR = 20), (OR = 22), (OR = 13), and (OR = 10) to be present in teat canal swabs than in milk samples. Differences between herds in NAS species distribution were found and were most pronounced for and a -like species. This information aids in the understanding of NAS species as an etiology of IMI and should be taken into account when interpreting milk culture results.
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http://dx.doi.org/10.3389/fvets.2019.00186DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6582780PMC
June 2019

Benefits of Outdoor Sports for Society. A Systematic Literature Review and Reflections on Evidence.

Int J Environ Res Public Health 2019 03 15;16(6). Epub 2019 Mar 15.

National Institute of Physical Education of Catalonia (INEFC), University of Barcelona (UB), Av. Estadi 12-22, 08038 Barcelona, Spain.

The combination of physical activity and being in nature is recognized as providing a range of significant benefits. The objective of this literature review was to compile an overview of the social benefits and costs associated with outdoor sports within the academic literature and to reflect on the quality of underlying evidence that supports the relationship. A systematic review was carried out with seven partners from different European countries, including Bulgaria, France, Germany, United Kingdom, Italy, Portugal, and Spain. From a total of 17,560 studies identified, 133 studies were selected with relevant data extracted to standardized forms. The selected studies have been analyzed with qualitative research methods. A meta-analysis could not be conducted due to the heterogeneity of the study designs and outcome measures. As a result, the review gives an overview of the social impacts associated with outdoor sports which have been clustered to six broad categories: physical health, mental health and wellbeing, education and lifelong learning, active citizenship, crime reduction, and anti-social behavior, as well as additional benefits. The review furthermore revealed gaps in the evidence base which are especially notable in the long-term effects that outdoor sports can have on personal and social development.
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http://dx.doi.org/10.3390/ijerph16060937DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6466442PMC
March 2019

Correction for Gómez-Sanz et al., "First Staphylococcal Cassette Chromosome Containing a -Carrying Gene Complex Independent of Transposon Tn in a Macrococcus caseolyticus Isolate from a Canine Infection".

Antimicrob Agents Chemother 2018 11 24;62(11). Epub 2018 Oct 24.

Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Bern, Bern, Switzerland.

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http://dx.doi.org/10.1128/AAC.01916-18DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6201114PMC
November 2018

Biophysical Screening of a Focused Library for the Discovery of CYP121 Inhibitors as Novel Antimycobacterials.

ChemMedChem 2017 10 26;12(19):1616-1626. Epub 2017 Sep 26.

Helmholtz Institute for Pharmaceutical Research Saarland, HIPS, Department for Drug Design and Optimization, Campus E8.1, 66123, Saarbrücken, Germany.

The development of novel antimycobacterial agents against Mycobacterium tuberculosis (Mtb) is urgently required due to the appearance of multidrug resistance (MDR) combined with complicated long-term treatment. CYP121 was shown to be a promising novel target for inhibition of mycobacterial growth. In this study, we describe the rational discovery of new CYP121 inhibitors by a systematic screening based on biophysical and microbiological methods. The best hits originating from only one structural class gave initial information about molecular motifs required for binding and activity. The initial screening procedure was followed by mode-of-action studies and further biological characterizations. The results demonstrate superior antimycobacterial efficacy and a decreased toxicity profile of our frontrunner compound relative to the reference compound econazole. Due to its low molecular weight, promising biological profile, and physicochemical properties, this compound is an excellent starting point for further rational optimization.
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http://dx.doi.org/10.1002/cmdc.201700363DOI Listing
October 2017

Macrococcus canis sp. nov., a skin bacterium associated with infections in dogs.

Int J Syst Evol Microbiol 2017 Mar 3;67(3):621-626. Epub 2017 Apr 3.

Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Bern, Bern.

Gram-stain-positive cocci were isolated from miscellaneous sites of the skin of healthy dogs as well as from infection sites in dogs. The closest relative by sequencing of the 16S rRNA gene was Macrococcus caseolyticus with 99.7 % sequence identity, but compared with M. caseolyticus, the novel strains shared only 90.8 to 93.5 % DNA sequence identity with cpn60, dnaJ, rpoB and sodA partial genes, respectively. The novel strains also exhibited differential phenotypic characteristics from M. caseolyticus, and the majority displayed a visible haemolysis on sheep blood agar, while M. caseolyticus did not have any haemolytic activity. They generated different matrix-assisted laser-desorption/ionization time-of-flight (MALDI-TOF) MS spectral profiles compared with the other species of the genus Macrococcus. Furthermore, strain KM 45013 shared only 53.7 % DNA-DNA relatedness with the type strain of M. caseolyticus, confirming that they do not belong to the same species. The DNA G+C content of strain KM 45013 was 36.9 mol%. The most abundant fatty acids were C14 : 0, C18 : 3ω6c (6, 9, 12) and C16 : 0 n alcohol. MK-6 was the menaquinone type of KM 45013. Cell-wall structure analysis revealed that the peptidoglycan type was A3α l-Lys-Gly2-l-Ser. Based on genotypic and chemotaxonomic characteristics, we propose to classify these strains within a novel species of the genus Macrococcus for which the name Macrococcus canis sp. nov. is proposed. The type strain is KM 45013 (=DSM 101690=CCOS 969=CCUG 68920).
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http://dx.doi.org/10.1099/ijsem.0.001673DOI Listing
March 2017

Structure-Activity Relationships of 2-Sufonylpyrimidines as Quorum-Sensing Inhibitors to Tackle Biofilm Formation and eDNA Release of Pseudomonas aeruginosa.

ChemMedChem 2016 11 12;11(22):2522-2533. Epub 2016 Oct 12.

Helmholtz Institute for Pharmaceutical Research Saarland, Department of Drug Design and Optimization, Campus E 8.1, 66123, Saarbrücken, Germany.

Drug-resistant Pseudomonas aeruginosa (PA) strains are on the rise, making treatment with current antibiotics ineffective. Hence, circumventing resistance or restoring the activity of antibiotics by novel approaches is of high demand. Targeting the Pseudomonas quinolone signal quorum sensing (PQS-QS) system is an intriguing strategy to abolish PA pathogenicity without affecting the viability of the pathogen. Herein we report the structure-activity relationships of 2-sulfonylpyrimidines, which were previously identified as dual-target inhibitors of the PQS receptor PqsR and the PQS synthase PqsD. The SAR elucidation was guided by a combined approach using ligand efficiency and ligand lipophilicity efficiency to select the most promising compounds. In addition, the most effective inhibitors were rationally modified by the guidance of QSAR using Hansch analyses. Finally, these inhibitors showed the capacity to decrease biofilm mass and extracellular DNA, which are important determinants for antibiotic resistance.
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http://dx.doi.org/10.1002/cmdc.201600419DOI Listing
November 2016

Discovery and Biophysical Evaluation of First Low Nanomolar Hits Targeting CYP125 of M. tuberculosis.

ChemMedChem 2016 Nov 28;11(21):2385-2391. Epub 2016 Sep 28.

Helmholtz Institute for Pharmaceutical Research Saarland, Department of Drug Design and Optimization, Campus E8.1, 66123, Saarbrücken, Germany.

Tuberculosis, which is predominantly caused by Mycobacterium tuberculosis (Mtb), is still the most lethal bacterial infection with 1.5 million casualties in 2014. Moreover, the fact that the appearance of resistant mutants and long-term treatment are coupled with economic problems in developing countries hampers an efficient therapy. Interference with the essential cholesterol metabolism of Mtb could be a promising novel strategy to fight Mtb infections. CYP125, a P450 enzyme in Mtb, has been shown to play an important role in this metabolic pathway. For this reason, we used a combined screening approach involving surface plasmon resonance spectroscopy and a heme coordination assay to identify new CYP125 binders by employing a focused P450-inhibitor library. We identified the first hits with high affinity and favorable ligand efficiencies. Furthermore, frontrunner compounds also showed selectivity toward CYP121 specific to Mtb and required for its survival. To date, these are the first compounds targeting CYP125 with low nanomolar affinity.
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http://dx.doi.org/10.1002/cmdc.201600361DOI Listing
November 2016

DEVRIESEASIS IN A PLUMED BASILISK (BASILISCUS PLUMIFRONS) AND CHINESE WATER DRAGONS (PHYSIGNATHUS COCINCINUS) IN A ZOOLOGIC COLLECTION.

J Zoo Wildl Med 2016 Mar;47(1):280-5

Devriesea agamarum is a Gram-positive bacterium that was first described in 2008 as a causative agent of disease in lizards. Until today, reports from several countries reported the presence of this bacterium in various lizard species, which suggests a wide distribution among lizard collections. Pathologic lesions ranged from proliferative dermatitis and cheilitis to abscesses in multiple organs and septicemia in single animals, as well as entire groups. Until now, disease caused by D. agamarum has been reported in several lizard species. Because the bacterium is only identified by 16S rRNA sequencing and no commercially available identification systems contain the agent in their database, it may be underdiagnosed. This report describes a series of fatal devrieseasis in plumed basilisks (Basiliscus plumifrons) and Chinese water dragons (Physignathus cocincinus) from a zoologic collection and extends the range of susceptible species. In 3 mo, five animals died with pyogranulomatous lesions in the subcutis, the coelomic cavity, or multiple organs. In all cases, diffuse swelling or focal skin elevations of different body parts were observed. Devriesea agamarum could be isolated from lesions in all animals. A subsequent clinical survey of the lizard collection including bacteriologic investigation of oral cavity swabs indicated that bearded dragons (Pogona vitticeps) were carriers of D. agamarum, which suggests that this species could be a source of infection with this pathogen.
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http://dx.doi.org/10.1638/2014-0184.1DOI Listing
March 2016

Application of Dual Inhibition Concept within Looped Autoregulatory Systems toward Antivirulence Agents against Pseudomonas aeruginosa Infections.

ACS Chem Biol 2016 05 1;11(5):1279-86. Epub 2016 Mar 1.

Helmholtz Institute for Pharmaceutical Research Saarland (HIPS) , Department for Drug Design and Optimization, Campus E8.1, 66123 Saarbrücken, Germany.

Pseudomonas aeruginosa quorum-sensing (QS) is a sophisticated network of genome-wide regulation triggered in response to population density. A major component is the self-inducing pseudomonas quinolone signal (PQS) QS system that regulates the production of several nonvital virulence- and biofilm-related determinants. Hence, QS circuitry is an attractive target for antivirulence agents with lowered resistance development potential and a good model to study the concept of polypharmacology in autoloop-regulated systems per se. Based on the finding that a combination of PqsR antagonist and PqsD inhibitor synergistically lowers pyocyanin, we have developed a dual-inhibitor compound of low molecular weight and high solubility that targets PQS transcriptional regulator (PqsR) and PqsD, a key enzyme in the biosynthesis of PQS-QS signal molecules (HHQ and PQS). In vitro, this compound markedly reduced virulence factor production and biofilm formation accompanied by a diminished content of extracellular DNA (eDNA). Additionally, coadministration with ciprofloxacin increased susceptibility of PA14 to antibiotic treatment under biofilm conditions. Finally, disruption of pathogenicity mechanisms was also assessed in vivo, with significantly increased survival of challenged larvae in a Galleria mellonella infection model. Favorable physicochemical properties and effects on virulence/biofilm establish a promising starting point for further optimization. In particular, the ability to address two targets of the PQS autoinduction cycle at the same time with a single compound holds great promise in achieving enhanced synergistic cellular effects while potentially lowering rates of resistance development.
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http://dx.doi.org/10.1021/acschembio.6b00117DOI Listing
May 2016

Crystal structure of 4-methyl-sulfanyl-2-(2H-tetra-zol-2-yl)pyrimidine.

Acta Crystallogr E Crystallogr Commun 2015 Dec 16;71(Pt 12):o1051-2. Epub 2015 Dec 16.

Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS), Department for Drug Design and Optimization (DDOP), Saarland University, Campus E8.1, D-66123 Saarbruecken, Germany; Department of Pharmacy, Pharmaceutical and Medicinal Chemistry, Saarland University, Campus C2.3, D-66123 Saarbruecken, Germany.

The title compound, C6H6N6S, crystallized with two independent mol-ecules (A and B) in the asymmetric unit. The conformation of the two mol-ecules differs slightly. While the tetra-zole ring is inclined to the pyrim-idene ring by 5.48 (7) and 4.24 (7)° in mol-ecules A and B, respectively, the N-C-S-C torsion angles of the thio-methyl groups differ by ca 180°. In the crystal, the A and B mol-ecules are linked via a C-H⋯N hydrogen bond. They stack along the b-axis direction forming columns within which there are weak π-π inter-actions present [shortest inter-centroid distance = 3.6933 (13) Å].
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http://dx.doi.org/10.1107/S2056989015023634DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4719974PMC
December 2015

First Staphylococcal Cassette Chromosome mec Containing a mecB-Carrying Gene Complex Independent of Transposon Tn6045 in a Macrococcus canis Isolate from a Canine Infection.

Antimicrob Agents Chemother 2015 08 18;59(8):4577-83. Epub 2015 May 18.

Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Bern, Bern, Switzerland

A methicillin-resistant mecB-positive Macrococcus canis (strain KM45013) was isolated from the nares of a dog with rhinitis. It contained a novel 39-kb transposon-defective complete mecB-carrying staphylococcal cassette chromosome mec element (SCCmecKM45013). SCCmecKM45013 contained 49 coding sequences (CDSs), was integrated at the 3' end of the chromosomal orfX gene, and was delimited at both ends by imperfect direct repeats functioning as integration site sequences (ISSs). SCCmecKM45013 presented two discontinuous regions of homology (SCCmec coverage of 35%) to the chromosomal and transposon Tn6045-associated SCCmec-like element of M. caseolyticus JCSC7096: (i) the mec gene complex (98.8% identity) and (ii) the ccr-carrying segment (91.8% identity). The mec gene complex, located at the right junction of the cassette, also carried the β-lactamase gene blaZm (mecRm-mecIm-mecB-blaZm). SCCmecKM45013 contained two cassette chromosome recombinase genes, ccrAm2 and ccrBm2, which shared 94.3% and 96.6% DNA identity with those of the SCCmec-like element of JCSC7096 but shared less than 52% DNA identity with the staphylococcal ccrAB and ccrC genes. Three distinct extrachromosomal circularized elements (the entire SCCmecKM45013, ΨSCCmecKM45013 lacking the ccr genes, and SCCKM45013 lacking mecB) flanked by one ISS copy, as well as the chromosomal regions remaining after excision, were detected. An unconventional circularized structure carrying the mecB gene complex was associated with two extensive direct repeat regions, which enclosed two open reading frames (ORFs) (ORF46 and ORF51) flanking the chromosomal mecB-carrying gene complex. This study revealed M. canis as a potential disease-associated bacterium in dogs and also unveiled an SCCmec element carrying mecB not associated with Tn6045 in the genus Macrococcus.
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http://dx.doi.org/10.1128/AAC.05064-14DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4505210PMC
August 2015

Uruburuella testudinis sp. nov., isolated from tortoise (Testudo).

Int J Syst Evol Microbiol 2015 Apr 29;65(Pt 4):1251-1255. Epub 2015 Jan 29.

Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Bern, Bern, Switzerland.

A polyphasic taxonomic analysis was carried out on 11 uncommon Gram-stain-negative, non-motile, catalase- and oxidase-positive, but indole-negative, bacterial strains isolated from tortoises. Phenotypically and genetically they represented a homogeneous group of organisms most closely related to, but distinct from, Uruburuella suis. In a reconstructed 16S rRNA gene tree they clustered on a monophyletic branch next to U. suis with gene similarities between strains of 99.5-100%, and of up to 98.2% with U. suis . DNA-DNA hybridization indicated the organisms represented a novel species with only 40% DNA-DNA similarity with U. suis . Partial sequencing of rpoB resulted in two subclusters confirming the 16S rRNA gene phylogeny; both genes allowed clear separation and identification of the novel species. Furthermore, they could be unambiguously identified by matrix-assisted laser desorption ionization time-of-flight MS, where, again, they formed a highly homogeneous cluster separate from U. suis and other members of the family Neisseriaceae . The major fatty acids were C(16 : 0) and summed feature C(16 : 1)ω7c/iso-C(15 : 0) 2-OH. The DNA G+C content was 54.4 mol%. Based on phenotypic and genetic data we propose classifying these organisms as representatives of a novel species named Uruburuella testudinis sp. nov. The type strain is 07_OD624(T) ( = DSM 26510(T) = CCUG 63373(T)).
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http://dx.doi.org/10.1099/ijs.0.000089DOI Listing
April 2015

Occurrence and genetic characteristics of third-generation cephalosporin-resistant Escherichia coli in Swiss retail meat.

Microb Drug Resist 2014 Oct 28;20(5):485-94. Epub 2014 Apr 28.

1 Vetsuisse Faculty, Institute of Veterinary Bacteriology, University of Bern , Bern, Switzerland .

Prevalence and genetic relatedness were determined for third-generation cephalosporin-resistant Escherichia coli (3GC-R-Ec) detected in Swiss beef, veal, pork, and poultry retail meat. Samples from meat-packing plants (MPPs) processing 70% of the slaughtered animals in Switzerland were purchased at different intervals between April and June 2013 and analyzed. Sixty-nine 3GC-R-Ec isolates were obtained and characterized by microarray, PCR/DNA sequencing, Multi Locus Sequence Typing (MLST), and plasmid replicon typing. Plasmids of selected strains were transformed by electroporation into E. coli TOP10 cells and analyzed by plasmid MLST. The prevalence of 3GC-R-Ec was 73.3% in chicken and 2% in beef meat. No 3GC-R-Ec were found in pork and veal. Overall, the bla(CTX-M-1) (79.4%), bla(CMY-2) (17.6%), bla(CMY-4) (1.5%), and bla(SHV-12) (1.5%) β-lactamase genes were detected, as well as other genes conferring resistance to chloramphenicol (cmlA1-like), sulfonamides (sul), tetracycline (tet), and trimethoprim (dfrA). The 3GC-R-Ec from chicken meat often harbored virulence genes associated with avian pathogens. Plasmid incompatibility (Inc) groups IncI1, IncFIB, IncFII, and IncB/O were the most frequent. A high rate of clonality (e.g., ST1304, ST38, and ST93) among isolates from the same MPPs suggests that strains persist at the plant and spread to meat at the carcass-processing stage. Additionally, the presence of the blaCTX-M-1 gene on an IncI1 plasmid sequence type 3 (IncI1/pST3) in genetically diverse strains indicates interstrain spread of an epidemic plasmid. The bla(CMY-2) and bla(CMY-4) genes were located on IncB/O plasmids. This study represents the first comprehensive assessment of 3GC-R-Ec in meat in Switzerland. It demonstrates the need for monitoring contaminants and for the adaptation of the Hazard Analysis and Critical Control Point concept to avoid the spread of multidrug-resistant bacteria through the food chain.
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http://dx.doi.org/10.1089/mdr.2013.0210DOI Listing
October 2014

Genotypes and antibiotic resistance of canine Campylobacter jejuni isolates.

Vet Microbiol 2014 Jan 22;168(1):124-30. Epub 2013 Oct 22.

Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Bern, Bern, Switzerland. Electronic address:

Campylobacter jejuni is the most important cause of bacterial gastroenteritis in humans. It is a commensal in many wild and domestic animals, including dogs. Whereas genotypes of human and chicken C. jejuni isolates have been described in some detail, only little information on canine C. jejuni genotypes is available. To gain more information on genotypes of canine C. jejuni and their zoonotic potential, isolates from routine diagnostics of diarrheic dogs as well as isolates of a prevalence study in non-diarrheic dogs were analyzed. Prevalence of thermophilic Campylobacter among non-diarrheic dogs was 6.3% for C. jejuni, 5.9% for Campylobacter upsaliensis and 0.7% for Campylobacter coli. The C. jejuni isolates were genotyped by multi locus sequence typing (MLST) and flaB typing. Resistance to macrolides and quinolones was genetically determined in parallel. Within the 134 genotyped C. jejuni isolates 57 different sequence types (ST) were found. Five STs were previously unrecognized. The most common STs were ST-48 (11.2%), ST-45 (10.5%) and ST-21 (6.0%). Whereas no macrolide resistance was found, 28 isolates (20.9%) were resistant to quinolones. ST-45 was significantly more prevalent in diarrheic than in non-diarrheic dogs. Within the common time frame of isolation 94% of the canine isolates had a ST that was also found in human clinical isolates. In conclusion, prevalence of C. jejuni in Swiss dogs is low but there is a large genetic overlap between dog and human isolates. Given the close contact between human and dogs, the latter should not be ignored as a potential source of human campylobacteriosis.
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http://dx.doi.org/10.1016/j.vetmic.2013.10.006DOI Listing
January 2014

Mycoplasma feriruminatoris sp. nov., a fast growing Mycoplasma species isolated from wild Caprinae.

Syst Appl Microbiol 2013 Dec 6;36(8):533-8. Epub 2013 Sep 6.

International Livestock Research Institute, PO Box 30709, 00100 Nairobi, Kenya. Electronic address:

Five Mycoplasma strains from wild Caprinae were analyzed: four from Alpine ibex (Capra ibex) which died at the Berlin Zoo between 1993 and 1994, one from a Rocky Mountain goat collected in the USA prior to 1987. These five strains represented a population different from the populations belonging to the 'Mycoplasma mycoides cluster' as tested using multi locus sequence typing, Matrix-assisted laser desorption/ionization time of flight mass spectrometry analysis and DNA-DNA hybridization. Analysis of the 16S rRNA gene (rrs), genomic sequence based in silico as well as laboratory DNA-DNA hybridization, and the analysis of phenotypic traits in particular their exceptionally rapid growth all confirmed that they do not belong to any Mycoplasma species described to date. We therefore suggest these strains represent a novel species, for which we propose the name Mycoplasma feriruminatoris sp. nov. The type strain is G5847(T) (=DSM 26019(T)=NCTC 13622(T)) [corrected].
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http://dx.doi.org/10.1016/j.syapm.2013.07.005DOI Listing
December 2013

Arsenicicoccus dermatophilus sp. nov., a hypha-forming bacterium isolated from the skin of greater flamingos (Phoenicopterus roseus) with pododermatitis.

Int J Syst Evol Microbiol 2013 Nov 31;63(Pt 11):4046-4051. Epub 2013 May 31.

Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Bern, Bern, Switzerland.

Dermatophilus-like bacteria were observed in histological examinations of samples of diseased foot skin from greater flamingos (Phoenicopterus roseus) living in zoological gardens in Switzerland. When grown on TSA-SB containing polymyxin B, the bacteria isolated from these skin samples formed hyphae, as is typical for Dermatophilus congolensis, but these bacteria were non-haemolytic. The closest relatives based on 16S rRNA gene sequences were the two members of the genus Arsenicicoccus, Arsenicicoccus bolidensis and Arsenicicoccus piscis. A representative of the isolated strains shared 34.3 % DNA-DNA relatedness with the type strain of A. bolidensis, 32.3 % with the type strain of A. piscis and 34.5 % with the type strain of D. congolensis, demonstrating that these strains do not belong to any of these species. The phenotypic characteristics differed from those of members of the genus Arsenicicoccus as well as from those of D. congolensis. The G+C content of strain KM 894/11(T) was 71.6 mol%. The most abundant fatty acids were iso-C15 : 0, summed feature 3 (including C16 : 1ω7c and/or iso-C15 : 0 2-OH) and C18 : 1ω9c. MK-8(H4) was the predominant menaquinone. Cell-wall structure analysis revealed that the peptidoglycan type was A3γ ll-Dpm-Gly (type A41.1). Based on genotypic and chemotaxonomic characteristics, the isolated strains represent a novel species within the genus Arsenicicoccus, for which the name Arsenicicoccus dermatophilus sp. nov. is proposed. The type strain is KM 894/11(T) ( = DSM 25571(T) = CCUG 62181(T) = CCOS 690(T)), and strain KM 1/12 ( = DSM 25572 = CCUG 62182 = CCOS 691) is a reference strain.
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http://dx.doi.org/10.1099/ijs.0.048546-0DOI Listing
November 2013

Evaluation of PCR electrospray-ionization mass spectrometry for rapid molecular diagnosis of bovine mastitis.

J Dairy Sci 2013 Jun 12;96(6):3611-20. Epub 2013 Apr 12.

Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Bern, Bern, Switzerland.

Bovine mastitis, an inflammatory disease of the mammary gland, is one of the most costly diseases affecting the dairy industry. The treatment and prevention of this disease is linked heavily to the use of antibiotics in agriculture and early detection of the primary pathogen is essential to control the disease. Milk samples (n=67) from cows suffering from mastitis were analyzed for the presence of pathogens using PCR electrospray-ionization mass spectrometry (PCR/ESI-MS) and were compared with standard culture diagnostic methods. Concurrent identification of the primary mastitis pathogens was obtained for 64% of the tested milk samples, whereas divergent results were obtained for 27% of the samples. The PCR/ESI-MS failed to identify some of the primary pathogens in 18% of the samples, but identified other pathogens as well as microorganisms in samples that were negative by culture. The PCR/ESI-MS identified bacteria to the species level as well as yeasts and molds in samples that contained a mixed bacterial culture (9%). The sensitivity of the PCR/ESI-MS for the most common pathogens ranged from 57.1 to 100% and the specificity ranged from 69.8 to 100% using culture as gold standard. The PCR/ESI-MS also revealed the presence of the methicillin-resistant gene mecA in 16.2% of the milk samples, which correlated with the simultaneous detection of staphylococci including Staphylococcus aureus. We demonstrated that PCR/ESI-MS, a more rapid diagnostic platform compared with bacterial culture, has the significant potential to serve as an important screening method in the diagnosis of bovine clinical mastitis and has the capacity to be used in infection control programs for both subclinical and clinical disease.
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http://dx.doi.org/10.3168/jds.2012-6124DOI Listing
June 2013

Genetic characterization of antimicrobial resistance in coagulase-negative staphylococci from bovine mastitis milk.

J Dairy Sci 2013 Apr 15;96(4):2247-2257. Epub 2013 Feb 15.

Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Bern, CH-3012 Bern, Switzerland. Electronic address:

Coagulase-negative staphylococci (CNS; n=417) were isolated from bovine milk and identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Nineteen different species were identified, and Staphylococcus xylosus, Staphylococcus chromogenes, Staphylococcus haemolyticus, and Staphylococcus sciuri were the most prevalent species. Resistance to oxacillin (47.0% of the isolates), fusidic acid (33.8%), tiamulin (31.9%), penicillin (23.3%), tetracycline (15.8%), streptomycin (9.6%), erythromycin (7.0%), sulfonamides (5%), trimethoprim (4.3%), clindamycin (3.4%), kanamycin (2.4%), and gentamicin (2.4%) was detected. Resistance to oxacillin was attributed to the mecA gene in 9.7% of the oxacillin-resistant isolates. The remaining oxacillin-resistant CNS did not contain the mecC gene or mecA1 promoter mutations. The mecA gene was detected in Staphylococcus fleurettii, Staphylococcus epidermidis, Staph. haemolyticus, and Staph. xylosus. Resistance to tetracycline was attributed to the presence of tet(K) and tet(L), penicillin resistance to blaZ, streptomycin resistance to str and ant(6)-Ia, and erythromycin resistance to erm(C), erm(B), and msr. Resistance to tiamulin and fusidic acid could not be attributed to an acquired resistance gene. In total, 15.1% of the CNS isolates were multidrug resistant (i.e., resistant to 2 or more antimicrobials). The remaining CNS isolates were susceptible to antimicrobials commonly used in mastitis treatment. Methicillin-resistant CNS isolates were diverse, as determined by mecA gene sequence analysis, staphylococcal cassette chromosome mec typing, and pulsed-field gel electrophoresis. Arginine catabolic mobile element types 1 and 3 were detected in both methicillin-resistant and methicillin-susceptible Staph. epidermidis and were associated with sequence types ST59 and ST111. Because this study revealed the presence of multidrug-resistant CNS in a heterogeneous CNS population, we recommend antibiogram analysis of CNS in persistent infections before treatment with antimicrobials.
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http://dx.doi.org/10.3168/jds.2012-6091DOI Listing
April 2013

Dissecting fragment-based lead discovery at the von Hippel-Lindau protein:hypoxia inducible factor 1α protein-protein interface.

Chem Biol 2012 Oct;19(10):1300-12

Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK.

Fragment screening is widely used to identify attractive starting points for drug design. However, its potential and limitations to assess the tractability of often challenging protein:protein interfaces have been underexplored. Here, we address this question by means of a systematic deconstruction of lead-like inhibitors of the pVHL:HIF-1α interaction into their component fragments. Using biophysical techniques commonly employed for screening, we could only detect binding of fragments that violate the Rule of Three, are more complex than those typically screened against classical druggable targets, and occupy two adjacent binding subsites at the interface rather than just one. Analyses based on ligand and group lipophilicity efficiency of anchored fragments were applied to dissect the individual subsites and probe for binding hot spots. The implications of our findings for targeting protein interfaces by fragment-based approaches are discussed.
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http://dx.doi.org/10.1016/j.chembiol.2012.08.015DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3551621PMC
October 2012

Risk factors for contacts between wild boar and outdoor pigs in Switzerland and investigations on potential Brucella suis spill-over.

BMC Vet Res 2012 Jul 20;8:116. Epub 2012 Jul 20.

Centre for Fish and Wildlife Health (FIWI), Institute of Animal Pathology, Vetsuisse Faculty, University of Bern, Bern, Switzerland.

Background: Due to the parallel increase of the number of free-ranging wild boar and domestic pigs reared outdoor, the risk that they interact has become higher. Contacts with wild boar can be the origin of disease outbreaks in pigs, as it has been documented for brucellosis in some European countries. This study aimed at quantifying the occurrence of contacts between wild boar and outdoor domestic pigs in Switzerland, and identifying risk factors for these contacts. Furthermore, exposed pigs were tested for pathogen spill-over, taking Brucella suis as an example because B. suis is widespread in Swiss wild boar while domestic pigs are officially free of brucellosis.

Results: Thirty-one percent of the game-wardens and 25% of the pig owners participating to a country-wide questionnaire survey reported contacts, including approaches of wild boar outside the fence, intrusions, and mating. Seventeen piggeries (5%) reported the birth of cross-bred animals. Risk factors for contacts identified by a uni- and multivariable logistic regression approach were: distance between pig enclosure and buildings, proximity of a forest, electric fences, and fences ≤ 60 cm. Pigs of the Mangalitza breed were most at risk for mating with wild boar (births of cross-bred animals). Blood and tissues of 218 outdoor pigs from 13 piggeries were tested for an infection with Brucella suis, using rose bengal test, complement fixation test, and an IS711-based real-time PCR. One piggery with previous wild boar contacts was found infected with B. suis, however, epidemiological investigations failed to identify the direct source of infection.

Conclusions: Results show that interactions between wild boar and outdoor pigs are not uncommon, pointing at the existing risk of pathogen spill-over. Provided data on risk factors for these interactions could help the risk-based implementation of protection measures for piggeries. The documentation of a brucellosis outbreak in pigs despite the freedom-of-disease status underlines the importance of improving pathogen surveillance strategies and increasing disease awareness of farmers and veterinary practitioners.
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http://dx.doi.org/10.1186/1746-6148-8-116DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3464720PMC
July 2012

A novel isolation method of Brucella species and molecular tracking of Brucella suis biovar 2 in domestic and wild animals.

Vet Microbiol 2011 Jun 5;150(3-4):405-10. Epub 2011 Mar 5.

Centre for Zoonoses, Bacterial Animal Diseases and Antimicrobial Resistance (ZOBA), Länggass-Strasse 122, Postfach 8466, CH-3001 Bern, Switzerland.

Brucella suis biovar 2 is the most common aetiological agent of porcine brucellosis in Europe. B. suis biovar 2 is considered to have low zoonotic potential, but is a causative agent of reproductive losses in pigs, and it is thus economically important. The multilocus variable-number of tandem repeats genotyping analysis of 16 loci (MLVA-16) has proven to be highly discriminatory and is the most suitable assay for simultaneously identifying B. suis and tracking infections. The aim of this study was to investigate the relatedness between isolates of B. suis biovar 2 obtained during a brucellosis outbreak in domestic pigs and isolates from wild boars and hares collected from proximal or remote geographical areas by MLVA-16. A cluster analysis of the MLVA-16 data revealed that most of the isolates obtained from Switzerland clustered together, with the exception of one isolate. The outbreak isolates constituted a unique subcluster (with a genetic similarity >93.8%) distinct from that of the isolates obtained from wild animals, suggesting that direct transmission of the bacterium from wild boars to domestic pigs did not occur in this outbreak. To obtain a representative number of isolates for MLVA-16, alternative methods of Brucella spp. isolation from tissue samples were compared with conventional direct cultivation on a Brucella-selective agar. We observed an enhanced sensitivity when mechanical homogenisation was followed by host cell lysis prior to cultivation on the Brucella-selective agar. This work demonstrates that MLVA-16 is an excellent tool for both monitoring brucellosis and investigating outbreaks. Additionally, we present efficient alternatives for the isolation of Brucella spp.
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http://dx.doi.org/10.1016/j.vetmic.2011.02.056DOI Listing
June 2011

IS711-based real-time PCR assay as a tool for detection of Brucella spp. in wild boars and comparison with bacterial isolation and serology.

BMC Vet Res 2009 Jul 14;5:22. Epub 2009 Jul 14.

National Centre for Zoonoses, Bacterial Animal Diseases and Antimicrobial Resistance (ZOBA), Institute of Veterinary Bacteriology, University of Bern, Vetsuisse Faculty, Länggass-Strasse 122, PO Box, CH-3001 Bern, Switzerland.

Background: Control of brucellosis in livestock, wildlife and humans depends on the reliability of the methods used for detection and identification of bacteria. In the present study, we describe the evaluation of the recently established real-time PCR assay based on the Brucella-specific insertion sequence IS711 with blood samples from 199 wild boars (first group of animals) and tissue samples from 53 wild boars (second group of animals) collected in Switzerland. Results from IS711 real-time PCR were compared to those obtained by bacterial isolation, Rose Bengal Test (RBT), competitive ELISA (c-ELISA) and indirect ELISA (i-ELISA).

Results: In the first group of animals, IS711 real-time PCR detected infection in 11.1% (16/144) of wild boars that were serologically negative. Serological tests showed different sensitivities [RBT 15.6%, c-ELISA 7.5% and i-ELISA 5.5%] and only 2% of blood samples were positive with all three tests, which makes interpretation of the serological results very difficult. Regarding the second group of animals, the IS711 real-time PCR detected infection in 26% of animals, while Brucella spp. could be isolated from tissues of only 9.4% of the animals.

Conclusion: The results presented here indicate that IS711 real-time PCR assay is a specific and sensitive tool for detection of Brucella spp. infections in wild boars. For this reason, we propose the employment of IS711 real-time PCR as a complementary tool in brucellosis screening programs and for confirmation of diagnosis in doubtful cases.
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http://dx.doi.org/10.1186/1746-6148-5-22DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2719624PMC
July 2009

Routine phenotypic identification of bacterial species of the family Pasteurellaceae isolated from animals.

J Vet Diagn Invest 2008 Nov;20(6):716-24

Institute of Veterinary Bacteriology, Universität Bern, Laenggasstrasse 122, Bern, Switzerland.

Pasteurellaceae are bacteria with an important role as primary or opportunistic, mainly respiratory, pathogens in domestic and wild animals. Some species of Pasteurellaceae cause severe diseases with high economic losses in commercial animal husbandry and are of great diagnostic concern. Because of new data on the phylogeny of Pasteurellaceae, their taxonomy has recently been revised profoundly, thus requiring an improved phenotypic differentiation procedure to identify the individual species of this family. A new and simplified procedure to identify species of Actinobacillus, Avibacterium, Gallibacterium, Haemophilus, Mannheimia, Nicoletella, and Pasteurella, which are most commonly isolated from clinical samples of diseased animals in veterinary diagnostic laboratories, is presented in the current study. The identification procedure was evaluated with 40 type and reference strains and with 267 strains from routine diagnostic analysis of various animal species, including 28 different bacterial species. Type, reference, and field strains were analyzed by 16S ribosomal RNA (rrs) and rpoB gene sequencing for unambiguous species determination as a basis to evaluate the phenotypic differentiation schema. Primary phenotypic differentiation is based on beta-nicotinamide adenine dinucleotide (beta-NAD) dependence and hemolysis, which are readily determined on the isolation medium. The procedure divides the 28 species into 4 groups for which particular biochemical reactions were chosen to identify the bacterial species. The phenotypic identification procedure allowed researchers to determine the species of 240 out of 267 field strains. The procedure is an easy and cost-effective system for the rapid identification of species of the Pasteurellaceae family isolated from clinical specimens of animals.
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http://dx.doi.org/10.1177/104063870802000602DOI Listing
November 2008

Antibiotic resistance in Lactococcus species from bovine milk: presence of a mutated multidrug transporter mdt(A) gene in susceptible Lactococcus garvieae strains.

Vet Microbiol 2008 Oct 30;131(3-4):348-57. Epub 2008 Mar 30.

Institute of Veterinary Bacteriology, University of Berne, CH-3001 Bern, Switzerland.

A total of 72 Lactococcus strains (41 Lactococcus lactis and 31 Lactococcus garvieae) isolated from bovine milk were tested for susceptibility to 17 antibiotics and screened for the presence of antibiotic resistance genes using a microarray. Resistance to tetracycline, clindamycin, erythromycin, streptomycin, nitrofurantoin were found. The tetracycline-resistant L. garvieae and L. lactis harbored tet(M) and tet(S). L. lactis that were resistant to clindamycin were also resistant to erythromycin and possessed the erm(B) gene. The multidrug transporter mdt(A), originally described in L. lactis, was detected for the first time in L. garvieae and does not confer decreased susceptibility to erythromycin nor tetracycline in this species. Mdt(A) of L. garvieae contains one mutation in each antiporter motif C, which is known to play an essential role in drug efflux antiporters. This suggests that the mutations found in the C-motifs of Mdt(A) from L. garvieae may be responsible for susceptibility. The study revealed the presence of antibiotic resistance genes in non-pathogenic and pathogenic lactococci from bovine milk, including a mutated multidrug transporter in L. garvieae.
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http://dx.doi.org/10.1016/j.vetmic.2008.03.008DOI Listing
October 2008

Presence of new mecA and mph(C) variants conferring antibiotic resistance in Staphylococcus spp. isolated from the skin of horses before and after clinic admission.

J Clin Microbiol 2006 Dec 27;44(12):4444-54. Epub 2006 Sep 27.

Institute of Veterinary Bacteriology, University of Berne, Länggass-Strasse 122, Postfach, CH-3001 Bern, Switzerland.

Because of the frequency of multiple antibiotic resistance, Staphylococcus species often represent a challenge in incisional infections of horses undergoing colic surgery. To investigate the evolution of antibiotic resistance patterns before and after preventative peri- and postoperative penicillin treatment, staphylococci were isolated from skin and wound samples at different times during hospitalization. Most staphylococci were normal skin commensals and belonged to the common coagulase-negative group. In some cases they turned out to be opportunistic pathogens present in wound infections. MICs were determined for 12 antibiotics, and antibiotic resistance genes were detected by microarray. At hospital admission, horses harbored staphylococci that were susceptible to antibiotics or resistant to one group of drugs, mainly due to the presence of new variants of the methicillin and macrolide resistance genes mecA and mph(C), respectively. After 3 days, the percentage of Staphylococcus isolates displaying antibiotic resistance, as well as the number of resistance genes per isolate, increased moderately in hospitalized horses without surgery or penicillin treatment but dramatically in hospitalized horses after colic surgery as well as penicillin treatment. Staphylococcus species displaying multiple resistance were found to harbor mainly genes conferring resistance to beta-lactams (mecA and blaZ), aminoglycosides [str and aac(6')-Ie-aph(2')-Ia], and trimethoprim [dfr(A) and dfr(D)]. Additional genes conferring resistance to macrolides [mph(C), erm(C), and erm(B)], tetracycline [tet(K) and tet(M)], chloramphenicol [cat(pC221) and cat(pC223)], and streptothricin (sat4) appeared in several strains. Hospitalization and preventive penicillin use were shown to act as selection agents for multidrug-resistant commensal staphylococcal flora.
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http://dx.doi.org/10.1128/JCM.00868-06DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1698435PMC
December 2006