Publications by authors named "Harish K Janagama"

The presence of microbial contaminants such as in wine can lead to undesirable wine. Therefore, monitoring for the presence of these spoilage organisms is critical for winemakers to ensure the quality of their end product. To address this problem, Molecular Epidemiology, Inc.

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The Microfilm™ Test System is intended for quantitative microbiology and consists of three types of Microfilms for aerobic plate count (Microfilm APC), total coliform and Escherichia coli count (Microfilm TCEc), and yeast and mold count (Microfilm YMC). This study evaluated the performance of the Microfilm Test System against International Organization for Standardization (ISO) methods on 20 food matrixes and 2 environmental surfaces. Ruggedness, robustness, and stability were also determined, while inclusivity and exclusivity studies were performed on Microfilm TCEc and YMC.

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Beer spoilage caused by wild yeast and bacteria is a major concern to both commercial and home brewers. To address this problem, Molecular Epidemiology Inc. (MEI, Seattle, WA) has developed a beer spoilage organism detection kit consisting of an enrichment media (BSE) and a multiplex PCR DNA dipstick that simultaneously detects these organisms within 2 h following enrichment.

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Article Synopsis
  • Maintaining intra-cellular pH is essential for bacteria like Mycobacterium avium subsp. paratuberculosis (MAP) to survive in acidic environments, yet the mechanisms of acid resistance in MAP are not well understood.
  • Researchers discovered that MAP0403, a predicted serine protease, plays a key role in MAP's acid stress response during infection, sharing significant similarity with MarP from M. tuberculosis.
  • Experiments showed that MAP0403 is upregulated in macrophages under acidic conditions, enhancing bacterial cell viability and suggesting it functions similarly to MarP in regulating internal pH and survival in acidic stress.
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The genus Megasphaera harbors important spoilage organisms that cause beer spoilage by producing off flavors, undesirable aroma, and turbidity. Megasphaera cerevisiae is mainly found in nonpasteurized low-alcohol beer. In this study, we report the draft genome of the type strain of the genus, M.

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Bovine tuberculosis remains one of the most damaging diseases to agriculture, and there is also a concern for human spillover. A critical need exists for rapid, thorough, and inexpensive diagnostic methods capable of detecting and differentiating Mycobacterium bovis infection from other pathogenic and environmental mycobacteria at multiple surveillance levels. In a previous study, Seth et al.

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Using a high throughput genetic strategy, designated Random Inducible Controlled Expression (RICE), we identified the six gene mel2 locus in Mtb and M. marinum. Interestingly, three of the genes present in mel2 have similarities to bioluminescence genes.

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We have developed Random Inducible Controlled Expression (RICE), a high throughput genetic approach to identify regulated virulence pathways in pathogenic mycobacteria. RICE allows expression of bacterial genes under conditions where they are normally off, e.g.

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Article Synopsis
  • Two distinct strains of Mycobacterium avium subsp. paratuberculosis (S and C MAP) have varying responses to iron in their growth mediums, which could affect their microbiological behaviors and pathogenicity.
  • S strains exhibit defective iron storage systems, leading to reduced expression of important proteins when iron is abundant, while C strains regulate iron storage and upregulate virulence factors under the same conditions.
  • Proteomic and transcriptional profiling revealed that the response to iron availability is uniquely adapted in C strains, suggesting it may have a competitive advantage in iron-replete environments compared to S strains.
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Background: Mycobacterium avium subsp. paratuberculosis (MAP) persistently infects intestines and mesenteric lymph nodes leading to a prolonged subclinical disease. The MAP genome sequence was published in 2005, yet its transcriptional organization in natural infection is unknown.

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Mycobacterium avium subspecies paratuberculosis (MAP), the causative agent of Johne's disease in cattle and sheep, has unique iron requirements in that it is mycobactin-dependent for cultivation in vitro. The iron-dependent regulator (IdeR) is a well-characterized global regulator responsible for maintaining iron homeostasis in Mycobacterium tuberculosis (MTB). We identified an orthologous segment in the MAP genome, MAP2827, with >93 % amino acid identity to MTB IdeR.

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Background: Bovine tuberculosis is a highly prevalent infectious disease of cattle worldwide; however, infection in the United States is limited to 0.01% of dairy herds. Thus detection of bovine TB is confounded by high background infection with M.

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In this study we investigated the ability of different Mycobacterium avium subsp. paratuberculosis (M. paratuberculosis) strains to survive in bovine monocyte-derived macrophages (MDMs) of cows naturally infected with M.

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Mycobacterium avium subsp. paratuberculosis is the causative agent of Johne's disease in animals and has been hypothesized to be associated with Crohn's disease in humans. Recently, M.

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Background: Mycobacterium avium subsp. paratuberculosis (MAP), the causative agent of Johne's disease (JD) persistently infects and survives within the host macrophages. While it is established that substantial genotypic variation exists among MAP, evidence for the correlates that associate specific MAP genotypes with clinical or sub-clinical disease phenotypes is presently unknown.

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