Abstract:
:The Esx secretion pathway is conserved across Gram-positive bacteria. Esx-1, the best-characterized system, is required for virulence of Mycobacterium tuberculosis, although its precise function during infection remains unclear. Esx-3, a paralogous system present in all mycobacterial species, is required for growth in vitro. Here, we demonstrate that mycobacteria lacking Esx-3 are defective in acquiring iron. To compete for the limited iron available in the host and the environment, these organisms use mycobactin, high-affinity iron-binding molecules. In the absence of Esx-3, mycobacteria synthesize mycobactin but are unable to use the bound iron and are impaired severely for growth during macrophage infection. Mycobacteria thus require a specialized secretion system for acquiring iron from siderophores.
journal_name
Proc Natl Acad Sci U S Aauthors
Siegrist MS,Unnikrishnan M,McConnell MJ,Borowsky M,Cheng TY,Siddiqi N,Fortune SM,Moody DB,Rubin EJdoi
10.1073/pnas.0900589106subject
Has Abstractpub_date
2009-11-03 00:00:00pages
18792-7issue
44eissn
0027-8424issn
1091-6490pii
0900589106journal_volume
106pub_type
杂志文章abstract::The endoplasmic reticulum (ER) plays an important role in peroxisome biogenesis; some peroxisomal membrane proteins are inserted into the ER and trafficked to peroxisomes in vesicles. These vesicles could also provide the phospholipids required for the growth of peroxisomal membranes, because peroxisomes lack phosphol...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0808321105
更新日期:2008-10-14 00:00:00
abstract::We previously characterized a methionine aminopeptidase (EC 3.4.11.18; Met-AP1; also called peptidase M) in Saccharomyces cerevisiae, which differs from its prokaryotic homologues in that it (i) contains an N-terminal zinc-finger domain and (ii) does not produce lethality when disrupted, although it does slow growth d...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.92.26.12357
更新日期:1995-12-19 00:00:00
abstract::Xanthophyll pigments have critical structural and functional roles in the photosynthetic light-harvesting complexes of algae and vascular plants. Genetic dissection of xanthophyll metabolism in the green alga Chlamydomonas reinhardtii revealed functions for specific xanthophylls in the nonradiative dissipation of exce...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.94.25.14162
更新日期:1997-12-09 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.89.23.11292
更新日期:1992-12-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2016-07-19 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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abstract::Microbial fatty acid derivatives are emerging as promising alternatives to fossil fuel derived transportation fuels. Among bacterial fatty acid synthases (FAS), the Escherichia coli FAS is perhaps the most well studied, but little is known about its steady-state kinetic behavior. Here we describe the reconstitution of...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2014-06-10 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2014-04-08 00:00:00
abstract::Residents in the marine intertidal, the zone where terrestrial and marine habitats converge, inhabit an environment that is subject to both the 24-h day and night daily rhythm of the terrestrial earth and also the 12.4-h ebb and flow of the tidal cycle. Here, we investigate the relative contribution of the daily and t...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2011-09-20 00:00:00
abstract::The molecular mechanism of desensitization of soluble guanylyl cyclase (sGC), the NO receptor, has long remained unresolved. Posttranslational modification and redox state have been postulated to affect sGC sensitivity to NO but evidence has been lacking. We now show that sGC can be S-nitrosylated in primary aortic sm...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2007-07-24 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0712199105
更新日期:2008-05-13 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章,评审
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2010-09-07 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2018-09-18 00:00:00
abstract::When deprived of D-glucose for 24 hr, chicken embryo fibroblasts exhibit a marked increase in hexose transport activity compared with that of control cells. Scatchard analysis of [3H]cytochalasin B binding to starved cell plasma membranes (46 pmol/mg) indicated a six-fold increase compared with fed cell plasma membran...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.79.7.2286
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abstract::Synaptic transmission of the light response from photoreceptors to second-order cells of the retina was studied with the whole-cell patch-clamp technique in tiger salamander (Ambystoma tigrinum) retinal slices. Synaptic strength is modulated by extracellular pH in a striking manner: Light-sensitive postsynaptic curren...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:1972-08-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1987-07-01 00:00:00
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abstract::The transcription factor zinc-finger protein Miz1 represses TNF-α-induced JNK activation and the repression is relieved upon TNF-α stimulation. However, the underlying mechanism is incompletely understood. Here we report that Miz1 interferes with the ubiquitin conjugating enzyme (E2) Ubc13 for binding to the RING doma...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2012-01-03 00:00:00
abstract::The cat-86 gene in plasmid pPL603 specifies chloramphenicol acetyltransferase (CAT) and is selectively expressed in Bacillus subtilis at a stage in sporulation in which internal spores are first observed (approximately T8). The gene is unexpressed in vegetatively growing cells. cat-86 expression and spore formation ar...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1981-05-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2011-08-02 00:00:00
abstract::The signature of mass-independent fractionation of quadruple sulfur stable isotopes (S-MIF) in Archean rocks, ice cores, and Martian meteorites provides a unique probe of the oxygen and sulfur cycles in the terrestrial and Martian paleoatmospheres. Its mechanistic origin, however, contains some uncertainties. Even for...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2018-08-21 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.82.2.612
更新日期:1985-01-01 00:00:00