Host-Microbe Biology
Research Article | Host-Microbe BiologyThe Cloacal Microbiome of Five Wild Duck Species Varies by Species and Influenza A Virus Infection StatusWaterfowl are natural reservoir species for influenza A virus (IAV). Thus, they maintain high levels of pathogen diversity, are asymptomatic to the infection, and also contribute to the risk of a global influenza pandemic. An individual’s microbiome is a critical part in how a vertebrate manages pathogens and illness. Here, we describe the cloacal microbiome of 300 wild ducks, from five species (four with previously undescribed...
Research Article | Host-Microbe BiologyIsolation and Characterization of the Novel Botulinum Neurotoxin A Subtype 6Botulinum neurotoxins (BoNTs) have proved to be an effective treatment for a large number of neuropathic conditions. BoNTs comprise a large family of zinc metalloproteases, but BoNT/A1 is used nearly exclusively for pharmaceutical purposes. The genetic inactivation of a second BoNT gene in the native strain enabled expression and isolation of a single BoNT/A6 from cultures. Its characterization indicated that BoNT/A subtype A6 has a...
Research Article | Host-Microbe BiologyCyclic Diguanylate Regulates Virulence Factor Genes via Multiple Riboswitches in Clostridium difficileIn Clostridium difficile, the signaling molecule c-di-GMP regulates multiple processes affecting its ability to cause disease, including swimming and surface motility, biofilm formation, toxin production, and intestinal colonization. In this study, we used RNA-seq to define the transcriptional regulon of c-di-GMP in...
Research Article | Host-Microbe BiologyTranscriptional Heterogeneity of Cryptococcus gattii VGII Compared with Non-VGII Lineages Underpins Key Pathogenicity PathwaysThe transcriptional profiles of related pathogens and their responses to host-induced stresses underpin their pathogenicity. Expression differences between related pathogens during host interaction can indicate when and how these genes contribute to virulence, ultimately informing new and improved treatment strategies for those diseases. In this paper, we compare the transcriptional profiles of five isolates representing four lineages...
Observation | Host-Microbe BiologyClostridial Butyrate Biosynthesis Enzymes Are Significantly Depleted in the Gut Microbiota of Nonobese Diabetic MiceAlterations of the gut microbiota early in age have been hypothesized to impact T1D autoimmune pathogenesis. In the NOD mouse model, protection from T1D has been found to operate via modulation of the composition of the intestinal microbiota during a critical early window of ontogeny, although little is known about microbiota functions related to T1D development. Here, we show which gut microbial functions are specifically associated...
Research Article | Host-Microbe BiologyGenome-Wide Association Analyses in the Model Rhizobium Ensifer melilotiGenome-wide association analyses are a powerful approach for identifying gene function. These analyses are becoming commonplace in studies of humans, domesticated animals, and crop plants but have rarely been conducted in bacteria. We applied association analyses to 20 traits measured in Ensifer meliloti, an agriculturally and ecologically important bacterium because...
Research Article | Host-Microbe BiologyThe Capsule of Cryptococcus neoformans Modulates Phagosomal pH through Its Acid-Base PropertiesCryptococcus neoformans is the causative agent of cryptococcosis, a devastating fungal disease that affects thousands of individuals worldwide. This fungus has the capacity to survive inside phagocytic cells, which contributes to persistence of infection and dissemination. One of the major antimicrobial mechanisms of host phagocytes is to acidify the phagosomal...
Research Article | Host-Microbe BiologyImpact of Engineered Expression of Mitochondrial Association Factor 1b on Toxoplasma gondii Infection and the Host Response in a Mouse ModelThe parasite Toxoplasma gondii currently infects approximately one-third of the world’s population and causes life-threatening toxoplasmosis in individuals with undeveloped or weakened immune systems. Current treatments are unable to cure T. gondii infection, leaving infected individuals with slow-...
Research Article | Host-Microbe BiologyOral Administration of Porphyromonas gingivalis Alters the Gut Microbiome and Serum MetabolomeIncreasing evidence suggest that alterations of the gut microbiome underlie metabolic disease pathology by modulating gut metabolite profiles. We have shown that orally administered Porphyromonas gingivalis, a representative periodontopathic bacterium, alters the gut microbiome; that may be a novel mechanism by which periodontitis increases the risk of various...
Research Article | Host-Microbe BiologyThe Genetic Transformation of Chlamydia pneumoniaeThe absence of tools for the genetic manipulation of C. pneumoniae has hampered research into all aspects of its biology. In this study, we established a novel reproducible method for C. pneumoniae transformation based on a plasmid shuttle vector system. We constructed a...