Detection, characterization, and persistence of Campylobacter hepaticus, the cause of spotty liver disease in layer hens.

A Campylobacter species was first described as the etiological agent of Spotty Liver Disease (SLD) in 2015 and subsequently named as Campylobacter hepaticus in 2016. The bacterium predominantly affects barn and/or free-range hens at peak lay, is fastidious and difficult to isolate, which has impeded elucidation of its sources, means of persistence and transmission. Ten farms from South-Eastern Australia, of which 7 were free range entities participated in the study.

A lipoglycopeptide antibiotic for Gram-positive biofilm-related infections.

Drug-resistant Gram-positive bacterial infections are still a substantial burden on the public health system, with two bacteria ( and ) accounting for over 1.5 million drug-resistant infections in the United States alone in 2017. In 2019, 250,000 deaths were attributed to these pathogens globally.

Spotty Liver Disease: A review of an ongoing challenge in commercial free-range egg production.

Spotty Liver Disease is an acute infectious disease of layer chickens that was likely first described in the USA and Canada in the 1950s and 1960's. The disease occurs almost exclusively in barn and free-range production systems. Outbreaks usually, but not exclusively occur in young layers (≅25 weeks) at peak of lay.

Brominated indoles from a marine mollusc inhibit inflammation in a murine model of acute lung injury.

New drug leads for the treatment of inflammation are urgently needed. Marine molluscs are widely used as traditional medicines for the treatment of inflammation. Here we report the positive effects of a hypobranchial gland (HBG) extract and the dominant bioactive compound 6-bromoisatin from the Muricidae mollusc Dicathais orbita, for reducing lipopolysaccharide (LPS) induced acute lung inflammation in a mouse model.

The Pneumococcal Alpha-Glycerophosphate Oxidase Enhances Nasopharyngeal Colonization through Binding to Host Glycoconjugates.

Streptococcus pneumoniae (the pneumococcus) is a major human pathogen, causing a broad spectrum of diseases including otitis media, pneumonia, bacteraemia and meningitis. Here we examined the role of a potential pneumococcal meningitis vaccine antigen, alpha-glycerophosphate oxidase (SpGlpO), in nasopharyngeal colonization. We found that serotype 4 and serotype 6A strains deficient in SpGlpO have significantly reduced capacity to colonize the nasopharynx of mice, and were significantly defective in adherence to human nasopharyngeal carcinoma cells in vitro.

The Variable Region of Pneumococcal Pathogenicity Island 1 Is Responsible for Unusually High Virulence of a Serotype 1 Isolate.

Streptococcus pneumoniae is the leading infectious cause of death in children in the world. However, the mechanisms that drive the progression from asymptomatic colonization to disease are poorly understood. Two virulence-associated genomic accessory regions (ARs) were deleted in a highly virulent serotype 1 clinical isolate (strain 4496) and examined for their contribution to pathogenesis.

Characterization of Pneumococcal Genes Involved in Bloodstream Invasion in a Mouse Model.

Streptococcus pneumoniae (the pneumococcus) continues to account for significant morbidity and mortality worldwide, causing life-threatening diseases such as pneumonia, bacteremia and meningitis, as well as less serious infections such as sinusitis, conjunctivitis and otitis media. Current polysaccharide vaccines are strictly serotype-specific and also drive the emergence of non-vaccine serotype strains. In this study, we used microarray analysis to compare gene expression patterns of either serotype 4 or serotype 6A pneumococci in the nasopharynx and blood of mice, as a model to identify genes involved in invasion of blood in the context of occult bacteremia in humans.

A functional genomics catalogue of activated transcription factors during pathogenesis of pneumococcal disease.

Background: Streptococcus pneumoniae (the pneumococcus) is the world's foremost microbial pathogen, killing more people each year than HIV, TB or malaria. The capacity to penetrate deeper host tissues contributes substantially to the ability of this organism to cause disease. Here we investigated, for the first time, functional genomics modulation of 3 pneumococcal strains (serotype 2 [D39], serotype 4 [WCH43] and serotype 6A [WCH16]) during transition from the nasopharynx to lungs to blood and to brain of mice at both promoter and domain activation levels.

A transcription factor contributes to pathogenesis and virulence in Streptococcus pneumoniae.

To date, the role of transcription factors (TFs) in the progression of disease for many pathogens is yet to be studied in detail. This is probably due to transient, and generally low expression levels of TFs, which are the central components controlling the expression of many genes during the course of infection. However, a small change in the expression or specificity of a TF can radically alter gene expression.

Comparative GO: a web application for comparative gene ontology and gene ontology-based gene selection in bacteria.

Unlabelled: The primary means of classifying new functions for genes and proteins relies on Gene Ontology (GO), which defines genes/proteins using a controlled vocabulary in terms of their Molecular Function, Biological Process and Cellular Component. The challenge is to present this information to researchers to compare and discover patterns in multiple datasets using visually comprehensible and user-friendly statistical reports. Importantly, while there are many GO resources available for eukaryotes, there are none suitable for simultaneous, graphical and statistical comparison between multiple datasets.

Identification of genes that contribute to the pathogenesis of invasive pneumococcal disease by in vivo transcriptomic analysis.

Streptococcus pneumoniae (the pneumococcus) continues to be responsible for a high level of global morbidity and mortality resulting from pneumonia, bacteremia, meningitis, and otitis media. Here we have used a novel technique involving niche-specific, genome-wide in vivo transcriptomic analyses to identify genes upregulated in distinct niches during pathogenesis after intranasal infection of mice with serotype 4 or 6A pneumococci. The analyses yielded 28 common, significantly upregulated genes in the lungs relative to those in the nasopharynx and 25 significantly upregulated genes in the blood relative to those in the lungs in both strains, some of which were previously unrecognized.

Identification of a novel pneumococcal vaccine antigen preferentially expressed during meningitis in mice.

Streptococcus pneumoniae is the most common cause of severe bacterial meningitis in children, the elderly, and immunocompromised individuals. To identify virulence factors preferentially expressed during meningitis, we conducted niche-specific genome-wide in vivo transcriptomic analysis after intranasal infection of mice with serotype 4 or 6A pneumococci. The expression of 34 bacterial genes was substantially altered in brain tissue of mice infected with either of the 2 strains.

Central role of manganese in regulation of stress responses, physiology, and metabolism in Streptococcus pneumoniae.

The importance of Mn(2+) for pneumococcal physiology and virulence has been studied extensively. However, the specific cellular role(s) for which Mn(2+) is required are yet to be fully elucidated. Here, we analyzed the effect of Mn(2+) limitation on the transcriptome and proteome of Streptococcus pneumoniae D39.

Investigation into the controversial association of Streptococcus gallolyticus with colorectal cancer and adenoma.

Background: The seroprevalence of IgG antibodies of Streptococcus gallolyticus subspecies gallolyticus, CIP 105428, was evaluated to investigate the controversial association of S. gallolyticus with colorectal carcinoma and adenoma in attempt to investigate the nature of such association if any, by exploring the mRNA expression of NF-kappaB and IL-8. Moreover, the serological behavior of S.

Pneumococcal histidine triad proteins are regulated by the Zn2+-dependent repressor AdcR and inhibit complement deposition through the recruitment of complement factor H.

The pneumococcal histidine triad (Pht) proteins are a recently recognized family of surface proteins, comprising 4 members: PhtA, PhtB, PhtD, and PhtE. They are being promoted for inclusion in a multicomponent pneumococcal protein vaccine currently under development, but to date, their biological functions and their relative contributions to pathogenesis have not been clarified. In this study, the involvement of these proteins in pneumococcal virulence was investigated in murine models of sepsis and pneumonia by using defined, nonpolar mutants of the respective genes in Streptococcus pneumoniae D39.

Pneumococcal virulence gene expression and host cytokine profiles during pathogenesis of invasive disease.

Pneumococcal disease continues to account for significant morbidity and mortality worldwide. For the development of novel prophylactic and therapeutic strategies against the disease spectrum, a complete understanding of pneumococcal behavior in vivo is necessary. We evaluated the expression patterns of the proven and putative virulence factor genes adcR, cbpA, cbpD, cbpG, cpsA, nanA, pcpA, piaA, ply, psaA, pspA, and spxB after intranasal infection of CD1 mice with serotype 2, 4, and 6A pneumococci by real-time reverse transcription-PCR.