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Background The beta-lactamase enzyme OXA-48 has spread widely in recent years in Enterobacteriaceae associated with man, disseminated primarily on incompatibility group L/M plasmids. OXA-48 confers resistance to carbapenems, important antimicrobials for treating highly resistant bacterial infections in humans. This enzyme has rarely been detected in bacteria from animals. Furthermore, the use of carbapenem compounds is not permitted in food-producing animals in Europe and to our knowledge has not been reported in food-producing animals globally. Methods Bacterial isolates from lesions in stranded, free-living, juvenile common seals (Phoca vitulina) were identified. Antimicrobial susceptibility testing and whole genome sequencing analysis were used to characterise antimicrobial resistance genes carried by the bacteria. Results Here, we report the detection of Klebsiella pneumoniae subspecies pneumoniae carrying the blaOXA-48 gene on an incompatibility group L/M plasmid from an infection in a common seal. Conclusion Evidence is accruing that marine mammals may be infected with bacteria originating from anthropogenic sources, such as human sewage, contaminating the environment.

A total of 502 Campylobacter jejuni isolates from poultry in 12 different European countries (10 of them the largest poultry production countries in Europe) were whole genome sequenced to examine the genomic diversity of fluoroquinolone resistant (FQ‐R) and susceptible (FQ‐S) C. jejuni across the poultry producing European countries and to determine whether the emergence of fluoroquinolone resistance among C. jejuni is related to the transmission through countries or to the selection through fluoroquinolone use in the individual countries. A high genomic diversity was observed. The isolates clustered in four main clusters. All trees revealed that the isolates were clustered according to the presence/absence of the gyrA mutations causing fluoroquinolone resistance and ST‐types. The cgMLST trees of only FQ‐R and FQ‐S isolates showed that isolates from the same country of origin were distributed into multiple clusters similarly to the trees combining FQ‐R and FQ‐S isolates. The different phylogenetic methods, ranging from single nucleotide polymorphisms analysis to gene‐by‐gene approaches such as rMLST, cgMLST, wgMLST and core genome tree, provided concordant results, but it is not known which is the most accurate method for identifying the country of origin of the isolates. Allele frequency analysis of isolates under this study and a selection of previously published C. jejuni genomes in ENA showed association of geographical origin of poultry C. jejuni populations between Romania‐Poland, Italy‐Germany‐England, Portugal‐The Netherlands and USA‐Luxemburg. Allele frequency and phylogenetic analysis indicated that the isolates from Finland were genetically different from C. jejuni populations from other European countries included in this study. Trade pattern and antimicrobial use in livestock were not significantly associated with allele frequency or populations of C. jejuni, but data available to investigate these associations were limited.

We report on the detection of a strain of antimicrobial-resistant bacteria with zoonotic potential identified in the UK for the first time. Livestock-associated meticillin resistant Staphylococcus aureus (LA-MRSA), clonal complex (CC) 398 is predominantly asymptomatic in livestock, with infrequent reports of opportunistic infections in farm workers.1 LA-MRSA CC398, spa type t899, was detected from UK animals, harbouring prophage φSa3-immune evasion cluster (IEC) genes, sak , scn and chp , markers for human adaptation, which have been absent from previously reported UK CC398 animal strains. 2, 3 In 2016, …

The aim of this work was to develop a molecular method using loop-mediated isothermal amplification (LAMP) for detection of extended spectrum β-lactamase (ESBL)-producing Enterobacteriaceae from meat, and to compare it with different isolation agars and microarrays. LAMP assays were developed for CTX-M groups 1, 2, and 9 and OXA-10-like genes. Chicken, lamb, beef, pork, and turkey samples were spiked with 10, 100, and 1,000 cfu/gram using 8 strains of ESBL-producing Enterobacteriaceae (CTX-M sequence types 1, 2, 3, 14, 15, OXA-11, SHV-2, TEM-52) +/- a mix of competitor organisms. Samples were enriched overnight in buffered peptone water (BPW) +/- antibacterials before plating to CHROMagar CTX, OXOID ESBL Brilliance agar, and MacConkey agar with 1 mg/L cefotaxime. Selected BPW broths were also tested using LAMP assays, microarrays and using cefpodoxime discs on agar. For isolation/detection of ESBL producers from beef, pork, lamb, and turkey spiked with 10 or 100 cfu/gram ESBL (natural flora only), all agars and the LAMP assays showed 100% sensitivity and specificity for ESBL spike strains. For chicken samples, both LAMP and chromogenic agars showed improved sensitivity and specificity for isolation of ESBLs compared with MacConkey agar, particularly with competitor bacteria added. In comparison, the cefpodoxime disc method and microarray showed reduced sensitivity.

The human pathogen Neisseria meningitidis is the major causative agent of bacterial meningitis. The organism is usually treated as a strict aerobe and is cultured under fully aerobic conditions in the laboratory. We demonstrate here that although N. meningitidis fails to grow under strictly anaerobic conditions, under oxygen limitation the bacterium expresses a denitrification pathway (reduction of nitrite to nitrous oxide via nitric oxide) and that this pathway supplements growth. The expression of the gene aniA, which encodes nitrite reductase, is regulated by oxygen depletion and nitrite availability via transcriptional regulator FNR and two-component sensor-regulator NarQ/NarP respectively. Completion of the two-step denitrification pathway requires nitric oxide (NO) reduction, which proceeds after NO has accumulated during batch growth under oxygen-limited conditions. During periods of NO accumulation both nitrite and NO reduction are observed aerobically, indicating N. meningitidis can act as an aerobic denitrifier. However, under steady-state conditions in which NO is maintained at a low concentration, oxygen respiration is favoured over denitrification. NO inhibits oxidase activity in N. meningitidis with an apparent Ki NO = 380 nM measured in intact cells. The high respiratory flux to nitrite after microaerobic growth and the finding that accumulation of the denitrification intermediate NO inhibits oxygen respiration support the view that denitrification is a pathway of major importance in N. meningitidis.

Lungworms ( Dictyocaulus viviparus ) are nematodes that cause parasitic bronchitis (husk or hoose) in cattle. Lungworm outbreaks in cattle can result in production losses from reduced weight gain, lowered milk yield and death in young calves.1 Lungworms may be controlled by the use of a live attenuated lungworm vaccine capable of stimulating extended immunity.2 Lungworm L3 larvae, which are crucial for transmission of lungworm, are harvested from calf faeces, irradiated and used to produce vaccines.3 These are screened for a range of diseases, including Leptospira , as part of stringent quality control checks to prevent vaccine contamination. Leptospira borgpetersenii serovar hardjo type hardjo-bovis is the most common Leptospira serovar in cattle.4 Transmission occurs via contaminated urine, and symptoms of infection are frequently subclinical. Leptospira can cause delayed breeding, abortions or weak calves, causing significant economic loss.5 All calves and lungworm used for vaccine production are screened for Leptospira using ELISA, where sensitivity and specificity vary, making diagnosis difficult.6 7 In this study, the authors describe the development of a molecular assay which may be used for the detection of pathogenic Leptospira in lungworm preparations. A real-time assay was designed for use on the MX3005p (Stratagene). The 16S rRNA Leptospira -specific primers used are as described previously,8 9 with the exception of the reverse primer …

METHICILLIN-resistant Staphylococcus aureus (MRSA) has been reported in human medicine as a cause of nosocomial and community-associated infections (Otter and French 2010). In veterinary medicine, MRSA strains have been identified in a wide range of animals and diseases (Leonard and Markey 2008, Fessler and others 2009, Huber and others 2010, Turkyilmaz and others 2010), thus it is considered an emerging threat with a high zoonotic potential (Juhasz-Kaszanyitzky and others 2007). MRSA sequence type (ST) 1, spa type (t) 127 has been mostly isolated from community-associated infections, but t127 has seldom been identified in bovine and swine (Hasman and others 2010). The present report regards a dairy cow with an intramammary infection by MRSA ST1, t127 that was investigated over an entire lactation and submitted to histological evaluation of mammary tissue to explore both bacterial molecular features and host immune response in the milk and mammary tissue. The study was performed because only a few mammary infections of the dairy cow by this particular strain have been reported and no information is available on the interaction between the bacteria and the mammary gland. A five-year-old Holstein-Friesian dairy cow from a closed herd located in Milano province, Italy, consisting of 25 lactating cows, showed an intramammary infection with S aureus in both right quarters. The isolate revealed a multidrug resistance profile by the agar-plate method, and PCR analysis (Costa and Palladini 2005) confirmed the presence of mecA genes in both isolates, which were consequently classified as MRSA. The farmer decided to antibiotic treat and dry off the animal, despite the …

Summary The ndh gene that encodes the non-proton-translocating NADH dehydrogenase II of Escherichia coli is anaerobically repressed by FNR. However, in the absence of FNR, ndh expression is enhanced by anaerobic growth in media containing amino acids. Two potential regulatory proteins that may be associated with this activation have previously been detected, Arr (amino acid response regulator) and Nbp (ndh-bind'mg protein). Studies with the heat-stable Nbp have now shown that it is present in E. coli grown both aerobicaliy and anaerobically in rich and minimal media, indicating that it is not specifically associated with the anaerobic enhancement of ndh expression. The Nbp activity of aerobic cultures was maximal during exponential growth phase (when ndh promoter activity is minimal) but fell rapidly as cultures entered stationary phase and ndh expression increased. Protein purification and mutant studies have further shown that Nbp is identical to the Fis protein (factor for inversion stimulation). Three major and two minor Nbp (Fis)-binding sites have been identified in the ndh promoter by gel retardation and DNase I footprinting. The major sites are centred at -123, 72 and +51, in decreasing order of binding affinity. At low concentrations, Nbp (Fis) increased transcription from the ndh promoter by up to 25%, whereas at higher concentrations it prevented RNA polymerase (RNAP) binding and open complex formation. Consequently, Nbp (Fis) can both activate and repress transcription from the ndh promoter. The results suggest that Nbp (Fis) serves to ensure that the energetically efficient proton-translocating NADH dehydrogenase I is used in preference to the non-proton translocating NADH dehydrogenase II during periods of rapid growth, by repressing expression of the ndh gene.