Publications by authors named "Bryon Nicholson"

This study investigated the influence of gut microbiome composition in modulating susceptibility to Mycoplasma hyopneumoniae in pigs. Thirty-two conventional M. hyopneumoniae free piglets were randomly selected from six different litters at 3 weeks of age and were experimentally inoculated with M.

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The Clermont scheme has been used for subtyping of since it was initially described in early 2000. Since then, researchers have used the scheme to type and sub-type commensal and pathogenic , such as extraintestinal pathogenic (ExPEC), and compare their phylogenetic assignment by pathogenicity, serogroup, distribution among ExPEC of different host species and complement of virulence and resistance traits. Here, we compare assignments of human and avian ExPEC and commensal using the old and revised Clermont schemes to determine if the new scheme provides a refined snapshot of isolate classification.

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Article Synopsis
  • NMEC is a leading cause of bacterial meningitis in newborns, linked to high mortality rates and long-term neurological issues.
  • The study focuses on the complete genome sequence of the NMEC O18 strain, which is particularly virulent.
  • This strain is characterized as O18ac:K1, ST416, highlighting its specific genetic traits associated with its virulence.
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Avian-pathogenic Escherichia coli (APEC) is the causative agent of colibacillosis, a disease that affects all facets of poultry production worldwide, resulting in multimillion dollar losses annually. Here, we report the genome sequence of an APEC O18 sequence type 95 (ST95) strain associated with disease in a chicken.

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Avian pathogenic Escherichia coli (APEC) is associated with colibacillosis in poultry. Here, we present the first complete sequence of an APEC strain of the O7:HNT serotype and ST73 sequence type, isolated from a broiler with cellulitis. Complete genomes of APEC with distinct genetic backgrounds may be useful for comparative analysis.

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Neonatal Meningitis Escherichia coli (NMEC) is one of the most common causes of neonatal bacterial meningitis in the US and elsewhere resulting in mortality or neurologic deficits in survivors. Large plasmids have been shown experimentally to increase the virulence of NMEC in the rat model of neonatal meningitis. Here, 9 ExPEC-like plasmids were isolated from NMEC and sequenced to identify the core and accessory plasmid genes of ExPEC-like virulence plasmids in NMEC and create an expanded plasmid phylogeny.

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Neonatal meningitis Escherichia coli K1 (NMEC) are thought to be transmitted from mothers to newborns during delivery or by nosocomial infections. However, the source of E. coli K1 causing these infections is not clear.

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Uropathogenic Escherichia coli (UPEC) is responsible for the majority of urinary tract infections (UTIs), which are some of the world's most common bacterial infections of humans. Here, we examined the role of FNR (fumarate and nitrate reduction), a well-known global regulator, in the pathogenesis of UPEC infections. We constructed an fnr deletion mutant of UPEC CFT073 and compared it to the wild type for changes in virulence, adherence, invasion, and expression of key virulence factors.

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Two-component signaling systems (TCSs) are major mechanisms by which bacteria adapt to environmental conditions. It follows then that TCSs would play important roles in the adaptation of pathogenic bacteria to host environments. However, no pathogen-associated TCS has been identified in uropathogenic Escherichia coli (UPEC).

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We established an automated screening method to characterize adhesion of Escherichia coli to intestinal porcine epithelial cells (IPEC-J2) and their probiotic activity against infection by enteropathogenic E. coli (EPEC). 104 intestinal E.

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Colibacillosis, caused by avian pathogenic Escherichia coli (APEC), is a significant disease, causing extensive animal and financial losses globally. Because of the significance of this disease, more knowledge is needed regarding APEC's mechanisms of virulence. Here, we present the fully closed genome sequence of a typical avian pathogenic E.

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Testing 1,666 fecal or intestinal samples from healthy and diarrheic pigs, we obtained hemolytic Escherichia coli isolates from 593 samples. Focusing on hemolytic E. coli isolates without virulence-associated genes (VAGs) typical for enteropathogens, we found that such isolates carried a broad variety of VAGs typical for extraintestinal pathogenic E.

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