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Intensive farming practices can increase exposure of animals to infectious agents against which antibiotics are used. Orally administered antibiotics are well known to cause dysbiosis. To counteract dysbiotic effects, numerous studies in the past two decades sought to understand whether probiotics are a valid tool to help re-establish a healthy gut microbial community after antibiotic treatment. Although dysbiotic effects of antibiotics are well investigated, little is known about the effects of intramuscular antibiotic treatment on the gut microbiome and a few studies attempted to study treatment effects using phylogenetic diversity analysis techniques. In this study we sought to determine the effects of two probiotic- and one intramuscularly administered antibiotic treatment on the developing gut microbiome of post-weaning piglets between their 3rd and 9th week of life. Shotgun metagenomic sequences from over 800 faecal time-series samples derived from 126 post-weaning piglets and 42 sows were analysed in a phylogenetic framework. Differences between individual hosts such as breed, litter, and age, were found to be important contributors to variation in the community composition. Host age was the dominant factor in shaping the gut microbiota of piglets after weaning. The post-weaning pig gut microbiome appeared to follow a highly structured developmental program with characteristic post-weaning changes that can distinguish hosts that were born as little as two days apart in the second month of life. Treatment effects of the antibiotic and probiotic treatments were found but were subtle and included a higher representation of Mollicutes associated with intramuscular antibiotic treatment, and an increase of Lactobacillus associated with probiotic treatment. The discovery of correlations between experimental factors and microbial community composition is more commonly addressed with OTU-based methods and rarely analysed via phylogenetic diversity measures. The latter

The ability to swiftly respond to pathogen incursions relies heavily on fast and accurate diagnostics. Current published assays for citrus bacterial canker do not target Xanthomonas citri pv. citri, the causative agent, with high specificity when testing Australian samples. While the current diagnostics are useful in countries where canker is endemic, the detection of canker in Australia requires an emergency response. Close relatives to X. citri pv. citri found in Australia may generate false positives with the current recommended diagnostic assays. Therefore, we developed a more specific detection tool for citrus bacterial canker to provide greater diagnostic confidence for surveillance and eradication efforts. We used genomic comparisons of 161 Xanthomonad genomes and identified and confirmed genomic regions specific for X. citri pv. citri by performing local alignments of unique regions to reference genomes. We then developed loop-mediated isothermal amplification primers and validated them against a panel of 190 isolates to confirm specificity. Our diagnostic assay showed 100% corroboration with the concurrently developed multiplex primers and represents an improved diagnostic method capable of effective citrus bacterial canker identification.

Verticillium dahliae was isolated from Noogoora burr (Xanthium occidentale) seeds collected from mature asymptomatic plants in 2017 growing along the riverbank at Condobolin, NSW. V. dahliae was isolated from seeds by transferring surfaced-disinfested seed components onto 25% Potato Dextrose Agar (PDA) plus Novobiocin. Morphological and molecular analysis, as well as fulfilment of Koch’s postulates, confirmed the causal pathogen was V. dahliae. Additional analysis was carried out to assign the isolates into a vegetative compatibility group (VCG) and pathotype. This is the first report of V. dahliae VCG6 in Australia infecting X. occidentale.

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Results

Conclusions

ClimeFish is an on-going H2020 project committed to the study of the impacts of climate change on freshwater and marine fisheries and aquaculture across Europe. Regional climate models (RCM) feed biological models to forecast the biomass/production and distribution patterns of the target species studied by ClimeFish under the expected climate conditions in Europe by year 2050. This presentation focuses on the seven case studies for which risks and opportunities were identified, allowing the development of strategies to mitigate risks and utilize opportunities

The full Guideline for oxygen use in adults in healthcare and emergency settings, published in Thorax1 provides an update to the 2008 BTS Emergency oxygen guideline.2 The following is a summary of the recommendations and good practice points. The sections noted to within this summary refer to the full guideline sections.

Mycoplasma hyopneumoniae is the causative pathogen of porcine enzootic pneumonia, an economically significant disease that disrupts the mucociliary escalator in the swine respiratory tract. Expression of Mhp107, a P97 paralog encoded by the gene mhp107, was confirmed using ESI-MS/MS. To investigate the function of Mhp107, three recombinant proteins, F1Mhp107, F2 Mhp107, and F3Mhp107, spanning the N-terminal, central, and C-terminal regions of Mhp107 were constructed. Colonization of swine by M. hyopneumoniae requires adherence of the bacterium to ciliated cells of the respiratory tract. Recent studies have identified a number of M. hyopneumoniae adhesins that bind heparin, fibronectin, and plasminogen. F1Mhp107 was found to bind porcine heparin (KD ∼90 nM) in a dose-dependent and saturable manner, whereas F3Mhp107 bound fibronectin (K D ∼180 nM) at physiologically relevant concentrations. F1 Mhp107 also bound porcine plasminogen (KD = 24 nM) in a dose-dependent and physiologically relevant manner. Microspheres coated with F3Mhp107 mediate adherence to porcine kidney epithelial-like (PK15) cells, and all three recombinant proteins (F1Mhp107-F3 Mhp107) bound swine respiratory cilia. Together, these findings indicate that Mhp107 is a member of the multifunctional M. hyopneumoniae adhesin family of surface proteins and contributes to both adherence to the host and pathogenesis. © 2011 by The American Society for Biochemistry and Molecular Biology, Inc.

Campylobacter jejuni is a major gastrointestinal pathogen that colonizes host mucosa via interactions with extracellular matrix proteins, such as fibronectin (Fn). Fn-binding is mediated by a 37kDa outer membrane protein termed Campylobacter adherence Factor (CadF). The outer membrane protein profile of a recent gastrointestinal C. jejuni clinical isolate (JHH1) was analysed using 2-DE and MS. Several spots were identified as products of the cadF gene. These included mass and pI variants of 34 and 30 kDa, as well as 24 kDa (CadF24) and 22kDa (CadF22) mass variants. CadF variants were fully characterized by MALDI-TOF MS and MALDI-MS/MS. These data confirmed that CadF forms re-folding variants resulting in spots with lower mass and varying pI that are identical at the amino acid sequence level and are not modified posttranslationally. CadF22 and CadF24, however, were characterized as N-terminal, membrane-associated polypeptides resulting from cleavage between serine195 and leucine196, and glycine201 and phenylalanine202, respectively. These variants were more abundant in the virulent (O) isolate of C. jejuni NCTC11168 when compared with the avirulent (genome sequenced) isolate. Hexahistidine fusion constructs of full-length CadF (34 kDa), CadF24, and the deleted C-terminal OmpA domain (14 kDa; CadF14) were created in Escherichia coli. Recombinant CadF variants were probed against patient sera and revealed that only full-length CadF retained reactivity. Binding assays showed that CadF24 retained Fn-binding capability, while CadF14 did not bind Fn. These data suggest that the immunogenic epitope of CadF is cleaved to generate smaller Fnbinding polypeptides, which are not recognized by the host humoral response. CadF cleavage therefore may be associated with virulence in C. jejuni. © 2009 Wiley-VCH Verlag GmbH & Co. KGaA.

Porcine enzootic pneumonia is a chronic respiratory disease that affects swine. The etiological agent of the disease, Mycoplasma hyopneumoniae, is a bacterium that adheres to cilia of the swine respiratory tract, resulting in loss of cilia and epithelial cell damage. A M. hyopneumoniae protein P116, encoded by mhp108, was investigated as a potential adhesin. Examination of P116 expression using proteomic analyses observed P116 as a full-length protein and also as fragments, ranging from 17 to 70 kDa in size. A variety of pathogenic bacterial species have been shown to bind the extracellular matrix component fibronectin as an adherence mechanism. M. hyopneumoniae cells were found to bind fibronectin in a dose-dependent and saturable manner. Surface plasmon resonance was used to show that a recombinant C-terminal domain of P116 bound fibronectin at physiologically relevant concentrations (KD 24 ± 6 nM). Plasmin(ogen)-binding proteins are also expressed by many bacterial pathogens, facilitating extracellular matrix degradation. M. hyopneumoniae cells were found to also bind plasminogen in a dose-dependent and saturable manner; the C-terminal domain of P116 binds to plasminogen (KD 44 ± 5 nM). Plasminogen binding was abolished when the C-terminal lysine of P116 was deleted, implicating this residue as part of the plasminogen binding site. P116 fragments adhere to the PK15 porcine kidney epithelial-like cell line and swine respiratory cilia. Collectively these data suggest that P116 is an important adhesin and virulence factor of M. hyopneumoniae. © 2010 by The American Society for Biochemistry and Molecular Biology, Inc.

Campylobacter jejuni is the most common cause of bacterial gastroenteritis in the developed world. Immunoproteomics highlighted a 42-45 kDa antigen that comigrated on two-dimensional (2-DE) gels with the C. jejuni major outer membrane protein (MOMP). Predictive analysis revealed two candidates for the identity of the antigen, the most likely of which was the surface-associated lipoprotein, JlpA. Recombinant JlpA (rJlpA) reacted with patient sera, confirming that JlpA is antigenic. Polyclonal antibodies raised against rJlpA reacted against 3 JlpA mass variants from multiple C. jejuni. These variants differed by approximately 1.5 kDa, suggesting the presence of the N-linked C. jejuni glycan on two sites. Soybean agglutinin affinity and 2-DE purified 2 JlpA glycoforms (43.5 and 45 kDa). Their identities were confirmed using mass spectrometry following trypsin digest. Glycopeptides within JlpA variants were identified by proteinase-K digestion, graphite micropurification and MS-MS. Sites of glycosylation were confirmed as asparagines 107 and 146, both of which are flanked by the N-linked sequon. Sequence analysis confirmed that the N146 sequon is conserved in all C. jejuni genomes examined to date, while the N107 sequon is absent in the reference strain NCTC 11168. Western blotting confirmed the presence of only a single JlpA glycoform in both virulent (O) and avirulent (GS) isolates of NCTC 11168. MS analysis showed that JlpA exists as 3 discrete forms, unmodified, glycosylated at N146, and glycosylated at both N146/107, suggesting glycan addition at N146 is necessary for N107 glycosylation. Glycine extracts and Western blotting revealed that doubly glycosylated JlpA was the predominant form on the C. jejuni JHH1 surface; however, glycosylation is not required for antigenicity. This is the first study to identify N-linked glycosylation of a surface-exposed C. jejuni virulence factor and to show strain variation in glycosylation sites. © 2009 American Chemical Society.

Campylobacter jejuni is the leading cause of food- and water-borne illness world-wide. The membrane-associated proteome of a recent C. jejuni gastrointestinal isolate (JHH1) was generated by sodium carbonate precipitation and ultracentrifugation followed by 2-DE and MALDI-TOF MS as well as 2-DLC (strong cation exchange followed by RP chromatography) of trypsin digests coupled to MS/MS (2-DLC/MS/MS). 2-DE/MS identified 77 proteins, 44 of which were predicted membrane proteins, while 2-DLC/MS/MS identified 432 proteins, of which 206 were predicted to be membrane associated. Atotal of 453 unique proteins (27.4% ofthe C. jejuni theoretical proteome), including 187 bona fide membrane proteins were identified in this study. Membrane proteins were also compared between C. jejuni JHH1 and ATCC 700297 to identify factors potentially associated with increased gastrointestinal virulence. We identified 28 proteins that were significantly (>two-fold) more abundant in, or unique to, JHH1, including eight proteins involved in chemotaxis signal transduction and flagellar motility, the amino acid-binding surface antigens CjaA and CjaC, and four outer membrane proteins (OMPs) of unknown function (Cj0129c, Cj1031, Cj1279c, and Cj1721c). Immunoblotting using convalescent patient sera generated postgastrointestinal infection revealed 13 (JHH1) and 12 (ATCC 700297) immunoreactive proteins. These included flagellin (FlaA) and CadF as well as Omp18, Omp50, Cj1721c, PEB1A, PEB2, and PEB4A. This study provides a comprehensive analysis of membrane-associated proteins from C. jejuni. © 2008 Wiley-VCH Verlag GmbH & Co. KGaA.

Mycoplasma hyopneumoniae is the causative agent of porcine enzootic pneumonia, a chronic and economically significant respiratory disease that affects swine production worldwide. M. hyopneumoniae adheres to, and adversely affects the function of ciliated epithelial cells of the respiratory tract, and the cilium adhesin (P97), is intricately but not exclusively involved in this process. Although binding of pathogenic bacteria to glycosaminoglycans is a recognised step in pathogenesis, knowledge of glycosaminoglycan-binding proteins is lacking in M. hyopneumoniae. However, heparin and other sulfated polysaccharides are known to block the binding of M. hyopneumoniae to purified swine respiratory cilia. In this study, four regions within the cilium adhesin were examined for their ability to bind heparin. Cilium adhesin fragments comprising 653 amino acids of the N- terminus and 301 amino acids of the C-terminus (containing two repeat regions, R1 and R2) were cloned and expressed. These fragments bound heparin in a dose-dependent and saturable manner with physiologically significant binding affinities of 0.27±0.02 µM and 1.89±0.33 µM, respectively. Heparin binding of both fragments was strongly inhibited by the sulfated polysaccharides fucoidan and mucin but not by chondroitin sulfate B. When the C-terminal repeat regions R1 and R2 were cloned separately and expressed, heparin-binding activity was lost, suggesting that both regions are required for heparin binding. The ability of the cilium adhesin to bind heparin indicates that this molecule plays a multi-functional role in the adherence of M. hyopneumoniae to host respiratory surfaces and therefore has important implications with respect to the pathogenesis of this organism.

The ideological space created by the British Empire provided opportunities for explorations into the meanings of Victorian femininity. Woman could be the intrepid missionary, bringing light to dark Africa; the memsahib creating conflict in the colonies with her petty jealousies; or a vulnerable piece of her husband’s property to be defended from the ‘other’. She could also be the heroic mother responsible for the preservation of the race, or, simply an object of intensifying legal control over her reproductive capacities.