Project description:The present study describes a novel mechanism of antifungal resistance affecting the susceptibility of both the azole and echinocandin antifungals in an azole-resistant isolate from a matched pair of C. parapsilosis isolates obtained from a patient with prosthetic valve endocarditis. Transcriptome analysis indicated differential expression of several genes in the resistant isolate including upregulation of ERG1, ERG2, ERG5, ERG6, ERG11, ERG24, ERG25, ERG27, DAP1 and UPC2, of the ergosterol biosynthesis pathway. Whole genome sequencing revealed a mutation in the ERG3 gene leading to a G111R amino acid substitution in the resistant isolate. Subsequent introduction of this allele in the native ERG3 locus in the susceptible isolate resulted in a fluconazole MIC of >64 mg/ml and a caspofungin MIC of 8 mg/ml. Corresponding allelic replacement of the wildtype allele for the mutant allele in the resistant isolate resulted in a drop in MIC to 1 mg/ml for both fluconazole and caspofungin. Sterol profiles indicated a loss of sterol demethylase activity as a result of this mutation. This work demonstrate that this G111R mutation is wholly responsible for the resistant phenotype in the C. parapsilosis resistant isolate and is the first report of this multidrug resistance mechanism.
Project description:ETEC is an important human pathogen. Although the mechanism of diarrhea is known in ETEC, the regulatory networks are less understood. This study was conducted to understand the global expression of ETEC isolate E24377A under different growth and environemental conditions. ETEC isolate E24377A was grown in the presence of several chemical signals, including bile salts, glucose, and pre-conditioned media (PCM) from other enteric pathogens. E24377A was also grown to different densities, to see if a quorum sensing mechanism was in place
Project description:ETEC is an important human pathogen. Although the mechanism of diarrhea is known in ETEC, the regulatory networks are less understood. This study was conducted to understand the global expression of ETEC isolate E24377A under different growth and environemental conditions. ETEC isolate E24377A was grown in the presence of several chemical signals, including bile salts, glucose, and pre-conditioned media (PCM) from other enteric pathogens. E24377A was also grown to different densities, to see if a quorum sensing mechanism was in place The isolate was grown in different types of media, with different ammendments, and at different growth densities. The overall goal was to determine how expression gene expression changes in the presence of chemical signals; a special emphasis was placed on the expression of known and suspected virulence and colonization factors
Project description:We performed RNA-sequencing of Bgh-infected barley leaves at two different time-points after infection to examine gene expression in the barley powdery mildew isolate DH14 during plant pathogenesis.
Project description:Expression of the extensive arsenal of virulence factors by Streptococcus pyogenes are controlled by many regulators, of which covR/S is one of the best characterized and can influence ~15% of the genome. Animal models have established that mutants of CovR/S arise spontaneously in vivo resulting in highly invasive organisms. We analyzed a pharyngeal and a blood isolate of S. pyogenes recovered from the same individual 13 days apart. The two isolates varied in many phenotypic properties including speB production, which were reflected in transcriptome analyses. Pulsed field gel electrophoresis, multilocus sequence typing, and partial sequencing of some key genes failed to show any differences except for an 11-base insert in the covS gene in the blood isolate. These results showing that pharyngeal and blood isolates from a single individual which differ by a simple insertion, provide evidence for the model that regulatory gene mutations allow S. pyogenes to invade different niches in the body.
Project description:Time course: Interaction of Magnaporthe isolate TH6772 (of the host plant rice) with Hordeum vulgare, Ingrid (leaf epidermis) and Magnaporthe isolate CD180 (of Pennisetum) with Hordeum vulgare, Ingrid (leaf epidermis)
Project description:This SuperSeries is composed of the following subset Series: GSE27405: Transcriptional response of an azole-resistant Candida parapsilosis isolate [fluconazole]. GSE27407: Transcriptional response of an azole-resistant Candida parapsilosis isolate [posaconazole]. GSE27408: Transcriptional response of an azole-resistant Candida parapsilosis isolate [voriconazole]. Refer to individual Series
