Project description:A comparative genomic approach was used to identify large sequence polymorphisms among Mycobacterium avium isolates obtained from a variety of host species. DNA microarrays were used as a platform for comparing mycobacteria field isolates with the sequenced bovine isolate Mycobacterium avium subsp. paratuberculosis (Map) K10. ORFs were classified as present or divergent based on the relative fluorescent intensities of the experimental samples compared to Map K10 DNA. Map isolates cultured from cattle, bison, sheep, goat, avian, and human sources were hybridized to the Map microarray. Three large deletions were observed in the genomes of four Map isolates obtained from sheep and four clusters of ORFs homologous to sequences in the Mycobacterium avium subsp. avium (Maa) 104 genome were identified as being present in these isolates. One of these clusters encodes glycopeptidolipid biosynthesis enzymes. One of the Map sheep isolates had a genome profile similar to a group of Mycobacterium avium subsp. silvaticum (Mas) isolates which included four independent laboratory stocks of the organism traditionally identified as Maa strain 18. Genome diversity in Map appears to be mostly restricted to large sequence polymorphisms that are often associated with mobile genetic elements. Keywords: Comparative genomic hybridization
Project description:A comparative genomic approach was used to identify large sequence polymorphisms among Mycobacterium avium isolates obtained from a variety of host species. DNA microarrays were used as a platform for comparing mycobacteria field isolates with the sequenced bovine isolate Mycobacterium avium subsp. paratuberculosis (Map) K10. ORFs were classified as present or divergent based on the relative fluorescent intensities of the experimental samples compared to Map K10 DNA. Map isolates cultured from cattle, bison, sheep, goat, avian, and human sources were hybridized to the Map microarray. Three large deletions were observed in the genomes of four Map isolates obtained from sheep and four clusters of ORFs homologous to sequences in the Mycobacterium avium subsp. avium (Maa) 104 genome were identified as being present in these isolates. One of these clusters encodes glycopeptidolipid biosynthesis enzymes. One of the Map sheep isolates had a genome profile similar to a group of Mycobacterium avium subsp. silvaticum (Mas) isolates which included four independent laboratory stocks of the organism traditionally identified as Maa strain 18. Genome diversity in Map appears to be mostly restricted to large sequence polymorphisms that are often associated with mobile genetic elements. Keywords: Comparative genomic hybridization Each isolate was competitively hybridized against Map K10 with a minimum of 2 dye flip hybridizations per isolate.
Project description:Mycobacterium avium is a significant opportunistic intracellular pathogen in humans, pigs and birds. Human and porcine infection with M. avium is mainly due to M. avium subsp. hominissuis, whereas birds are typically infected with M. avium subsp. avium. Reasons for this distribution of subspecies between the hosts are uncertain, but they might be due to differences in exposure or to different abilities to infect the respective hosts. We wanted to assay how isolates of the two subspecies interact with a human host in a macrophage model to gain more knowledge on possible differences in virulence. This study compares clinical isolates of M. avium with regards to their ability to invade and replicate intracellularly in human monocytes/macrophages and to the gene expression triggered in these cells upon infection. Further focus in the description of protocols is limited to the parts of the study that regards the expression analysis.
Project description:To understand nontuberculous mycobacterial (NTM) pathogenesis, we evaluated immune responses to Mycobacterium avium (Mav) in asymptomatic individuals with a previous history of M. avium complex lung disease (MACDZ). We analyzed global gene expression in paired Mav-infected and uninfected peripheral blood monocytes from 17 MACDZ and 17 healthy controls.
Project description:We focused on how Mycobacterium avium subsp. paratuberculosis influences the subsequent host response to investigate the host immunopathology accompanying the host anti-mycobacterial immune response during Mycobacterium avium subsp. paratuberculosis infection in spleen of mice. We analyzed altered transcription in the spleen of mice at 3, 6, and 12 weeks following Mycobacterium avium subsp. paratuberculosis infection.
Project description:We focused on how Mycobacterium avium subsp. paratuberculosis influences the subsequent host response to investigate the host immunopathology accompanying the host anti-mycobacterial immune response during Mycobacterium avium subsp. paratuberculosis infection in spleen of mice.
Project description:This SuperSeries is composed of the following subset Series: GSE32241: Differentially regulated genes induced in Mycobacterium avium subspecies paratuberculosis by in vitro acid-nitrosative multi-stress GSE32242: Differentially regulated genes induced in Mycobacterium avium subspecies paratuberculosis by in vitro infection of THP-1 human macrophage cell line Refer to individual Series
Project description:Mycobacterium avium is the most common nontuberculous mycobacterium (NTM) species causing infectious disease. Here, we characterized a M. avium infection model in zebrafish larvae, and compared it to M. marinum infection, a model of tuberculosis. Using RNAseq analysis, we found a distinct transcriptome response in cytokine-cytokine receptor interaction for M. avium and M. marinum infection. In addition, we found substantial differences in gene expression in metabolic pathways, phagosome formation, matrix remodeling, and apoptosis in response to these mycobacterial infections.