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Abstract
Abstract
Disseminated infection caused by non-tuberculous mycobacteria (NTM) is very rare, with an incidence of 1.0 to 1.8 cases per 100,000 persons, and typically only occurs in severely immunocompromised hosts. Burn patients suffer loss of the natural cutaneous barrier as well as injury-induced immune dysfunction, and as a result, commonly develop infections, especially with multidrug-resistant organisms. However, very few NTM infections in burn patients have been reported in the literature. Disseminated NTM infection, in particular, can be a challenge to diagnose in burn patients due to burn related physiology such as hyperpyrexia and widespread skin injury. We present a case of disseminated infection leading to bacteremia caused by Mycobacterium abscessus in a critically ill burn patient with a 74% total body surface area burn. M. abscessus belongs to the subgroup of NTM known as rapidly growing mycobacteria (RGM), which are notable for their ability to form colonies in a matter of days, rather than weeks, and because they are often highly drug-resistant, which complicates antimicrobial therapy. This is the third reported case of bacteremia caused by NTM in a burn patient and the second case that was successfully transitioned from intravenous antimicrobials to an oral regimen.
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Affiliation(s)
- Emily H Hsu
- UC Davis Health, Department of Pharmacy, Sacramento, CA, USA
| | - Sierra Young
- UC Davis Health, Department of Pharmacy, Sacramento, CA, USA
| | - Nicola Clayton
- UC Davis Health, Department of Pharmacy, Sacramento, CA, USA
| | - Jin Lee
- UC Davis Health, Department of Pharmacy, Sacramento, CA, USA
| | - Naomi Hauser
- UC Davis Health, Division of Infectious Diseases, Department of Medicine, Sacramento, CA, USA
| | - Bennett Penn
- UC Davis Health, Division of Infectious Diseases, Department of Medicine, Sacramento, CA, USA
| | - Soman Sen
- UC Davis Health, Division of Burn Surgery, Department of Surgery, Sacramento, CA, USA
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Mirrashidi KM, Elwell CA, Verschueren E, Johnson JR, Frando A, Von Dollen J, Rosenberg O, Gulbahce N, Jang G, Johnson T, Jäger S, Gopalakrishnan AM, Sherry J, Dunn JD, Olive A, Penn B, Shales M, Cox JS, Starnbach MN, Derre I, Valdivia R, Krogan NJ, Engel J. Global Mapping of the Inc-Human Interactome Reveals that Retromer Restricts Chlamydia Infection. Cell Host Microbe 2015; 18:109-21. [PMID: 26118995 DOI: 10.1016/j.chom.2015.06.004] [Citation(s) in RCA: 138] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Revised: 04/28/2015] [Accepted: 06/05/2015] [Indexed: 01/02/2023]
Abstract
Chlamydia trachomatis is a leading cause of genital and ocular infections for which no vaccine exists. Upon entry into host cells, C. trachomatis resides within a membrane-bound compartment—the inclusion—and secretes inclusion membrane proteins (Incs) that are thought to modulate the host-bacterium interface. To expand our understanding of Inc function(s), we subjected putative C. trachomatis Incs to affinity purification-mass spectroscopy (AP-MS). We identified Inc-human interactions for 38/58 Incs with enrichment in host processes consistent with Chlamydia's intracellular life cycle. There is significant overlap between Inc targets and viral proteins, suggesting common pathogenic mechanisms among obligate intracellular microbes. IncE binds to sorting nexins (SNXs) 5/6, components of the retromer, which relocalizes SNX5/6 to the inclusion membrane and augments inclusion membrane tubulation. Depletion of retromer components enhances progeny production, revealing that retromer restricts Chlamydia infection. This study demonstrates the value of proteomics in unveiling host-pathogen interactions in genetically challenging microbes.
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Affiliation(s)
- Kathleen M Mirrashidi
- Department of Medicine, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Cherilyn A Elwell
- Department of Medicine, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Erik Verschueren
- QB3, California Institute for Quantitative Biosciences, San Francisco, CA 94148, USA; Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Jeffrey R Johnson
- QB3, California Institute for Quantitative Biosciences, San Francisco, CA 94148, USA; Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Andrew Frando
- Department of Medicine, University of California, San Francisco, San Francisco, CA 94143, USA
| | - John Von Dollen
- QB3, California Institute for Quantitative Biosciences, San Francisco, CA 94148, USA; Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Oren Rosenberg
- Department of Medicine, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Natali Gulbahce
- QB3, California Institute for Quantitative Biosciences, San Francisco, CA 94148, USA; Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Gwendolyn Jang
- QB3, California Institute for Quantitative Biosciences, San Francisco, CA 94148, USA; Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Tasha Johnson
- QB3, California Institute for Quantitative Biosciences, San Francisco, CA 94148, USA; Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Stefanie Jäger
- QB3, California Institute for Quantitative Biosciences, San Francisco, CA 94148, USA; Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94158, USA
| | | | - Jessica Sherry
- Department of Medicine, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Joe Dan Dunn
- Department of Molecular Genetics and Microbiology, Duke University, Durham, NC 27710, USA
| | - Andrew Olive
- Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA
| | - Bennett Penn
- Department of Medicine, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Michael Shales
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94158, USA; Gladstone Institutes, San Francisco, CA 94158, USA
| | - Jeffery S Cox
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA 94143, USA
| | | | - Isabelle Derre
- Department of Microbial Pathogenesis, Yale School of Medicine, New Haven, CT 06510, USA
| | - Raphael Valdivia
- Department of Molecular Genetics and Microbiology, Duke University, Durham, NC 27710, USA
| | - Nevan J Krogan
- QB3, California Institute for Quantitative Biosciences, San Francisco, CA 94148, USA; Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94158, USA; Gladstone Institutes, San Francisco, CA 94158, USA.
| | - Joanne Engel
- Department of Medicine, University of California, San Francisco, San Francisco, CA 94143, USA; Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA 94143, USA.
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Tavtigian SV, Simard J, Teng DH, Abtin V, Baumgard M, Beck A, Camp NJ, Carillo AR, Chen Y, Dayananth P, Desrochers M, Dumont M, Farnham JM, Frank D, Frye C, Ghaffari S, Gupte JS, Hu R, Iliev D, Janecki T, Kort EN, Laity KE, Leavitt A, Leblanc G, McArthur-Morrison J, Pederson A, Penn B, Peterson KT, Reid JE, Richards S, Schroeder M, Smith R, Snyder SC, Swedlund B, Swensen J, Thomas A, Tranchant M, Woodland AM, Labrie F, Skolnick MH, Neuhausen S, Rommens J, Cannon-Albright LA. A candidate prostate cancer susceptibility gene at chromosome 17p. Nat Genet 2001; 27:172-80. [PMID: 11175785 DOI: 10.1038/84808] [Citation(s) in RCA: 425] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
It is difficult to identify genes that predispose to prostate cancer due to late age at diagnosis, presence of phenocopies within high-risk pedigrees and genetic complexity. A genome-wide scan of large, high-risk pedigrees from Utah has provided evidence for linkage to a locus on chromosome 17p. We carried out positional cloning and mutation screening within the refined interval, identifying a gene, ELAC2, harboring mutations (including a frameshift and a nonconservative missense change) that segregate with prostate cancer in two pedigrees. In addition, two common missense variants in the gene are associated with the occurrence of prostate cancer. ELAC2 is a member of an uncharacterized gene family predicted to encode a metal-dependent hydrolase domain that is conserved among eukaryotes, archaebacteria and eubacteria. The gene product bears amino acid sequence similarity to two better understood protein families, namely the PSO2 (SNM1) DNA interstrand crosslink repair proteins and the 73-kD subunit of mRNA 3' end cleavage and polyadenylation specificity factor (CPSF73).
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Wong AK, Shanahan F, Chen Y, Lian L, Ha P, Hendricks K, Ghaffari S, Iliev D, Penn B, Woodland AM, Smith R, Salada G, Carillo A, Laity K, Gupte J, Swedlund B, Tavtigian SV, Teng DH, Lees E. BRG1, a component of the SWI-SNF complex, is mutated in multiple human tumor cell lines. Cancer Res 2000; 60:6171-7. [PMID: 11085541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Human BRG1 is a component of the evolutionarily conserved SWI-SNF chromatin remodeling complex. BRG1 has been implicated in growth control through its interaction with the tumor suppressor pRb and may consequently serve as a negative regulator of proliferation. Postulating that BRG1 may itself be a tumor suppressor gene, we screened a panel of tumor cell lines to determine whether the gene is targeted for mutation. We report that the COOH-terminal region of BRG1 is homozygously deleted in two carcinoma cell lines, prostate TSU-Pr1 and lung A-427. In addition, biallelic inactivations of BRG1 were observed in four other cell lines derived from carcinomas of the breast, lung, pancreas, and prostate; their mutations in BRG1 included three frameshift lesions and one nonsense lesion. Point mutations were also discovered in a number of other cell lines, however in most cases any effect of these mutations on BRG1 function remains to be established. A variety of different mutations within BRG1, in several cell lines, suggest that BRG1 may be targeted for disruption in human tumors. Significantly, reintroduction of BRG1 into cells lacking BRG1 expression was sufficient to reverse their transformed phenotype inducing growth arrest and a flattened morphology. These data strongly support the model that BRG1 may function as a tumor suppressor and strengthen the hypothesis that the regulation of gene expression through chromatin remodeling is critical for cancer progression. It will be important to confirm these observations in primary tumors.
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Affiliation(s)
- A K Wong
- Myriad Genetics, Inc., Salt Lake City, Utah 84108, USA
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Whitelegge JP, Penn B, To T, Johnson J, Waring A, Sherman M, Stevens RL, Fluharty CB, Faull KF, Fluharty AL. Methionine oxidation within the cerebroside-sulfate activator protein (CSAct or Saposin B). Protein Sci 2000; 9:1618-30. [PMID: 11045609 PMCID: PMC2144706 DOI: 10.1110/ps.9.9.1618] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The cerebroside-sulfate activator protein (CSAct or Saposin B) is a small water-soluble glycoprotein that plays an essential role in the metabolism of certain glycosphingolipids, especially sulfatide. Deficiency of CSAct in humans leads to sulfatide accumulation and neurodegenerative disease. CSAct activity can be measured in vitro by assay of its ability to activate sulfatide-sulfate hydrolysis by arylsulfatase A. CSAct has seven methionine residues and a mass of 8,845 Da when deglycosylated. Mildly oxidized, deglycosylated CSAct (+16 Da), separated from nonoxidized CSAct by reversed-phase high-performance liquid chromatography (RP-HPLC), showed significant modulation of the in vitro activity. Because oxidation partially protected against CNBr cleavage and could largely be reversed by treatment with dithiothreitol, it was concluded that the major modification was conversion of a single methionine to its sulfoxide. High-resolution RP-HPLC separated mildly oxidized CSAct into seven or more different components with shorter retention times than nonoxidized CSAct. Mass spectrometry showed these components to have identical mass (+16 Da). The shorter retention times are consistent with increased polarity accompanying oxidation of surface-exposed methionyl side chains, in general accordance with the existing molecular model. A mass-spectrometric CNBr mapping protocol allowed identification of five of the seven possible methionine-sulfoxide CSAct oxoforms. The most dramatic suppression of activity occurred upon oxidation of Met61 (26% of control) with other residues in the Q60MMMHMQ66 motif falling in the 30-50% activity range. Under conditions of oxidative stress, accumulation of minimally oxidized CSAct protein in vivo could perturb metabolism of sulfatide and other glycosphingolipids. This, in turn, could contribute to the onset and progression of neurodegenerative disease, especially in situations where the catabolism of these materials is marginal.
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Affiliation(s)
- J P Whitelegge
- Pasarow Mass Spectrometry Laboratory, University of California, Los Angeles 90095, USA.
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