Abstract:
:Conjugated linoleic acids (CLAs) affect body fat gain, carcinogenesis, insulin resistance, and lipid peroxidation in mammals. Several isomers of CLA exist, of which the (9Z, 11E) and (10E, 12Z) isomers have beneficial effects on human metabolism but are scarce in foods. Bacterial polyunsaturated fatty acid isomerases are promising biotechnological catalysts for CLA production. We describe six crystal structures of the Propionibacterium acnes polyunsaturated fatty acid isomerase PAI in apo- and product-bound forms. The three-domain flavoprotein has previously undescribed folds outside the FAD-binding site. Conformational changes in a hydrophobic channel toward the active site reveal a unique gating mechanism for substrate specificity. The geometry of the substrate-binding site explains the length preferences for C18 fatty acids. A catalytic mechanism for double-bond isomerization is formulated that may be altered to change substrate specificity for syntheses of rare CLAs from easily accessible precursors.
journal_name
Proc Natl Acad Sci U S Aauthors
Liavonchanka A,Hornung E,Feussner I,Rudolph MGdoi
10.1073/pnas.0510144103keywords:
subject
Has Abstractpub_date
2006-02-21 00:00:00pages
2576-81issue
8eissn
0027-8424issn
1091-6490pii
0510144103journal_volume
103pub_type
杂志文章abstract::The radial distributions of the Calpha and side-chain atoms in a sample of 13 native proteins have been examined. It is found that there are substantial differences in behavior between different atoms of the same amino acid. In particular, the Calpha atoms of polar residues show no particular preference for being far ...
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.74.12.5248
更新日期:1977-12-01 00:00:00
abstract::Twelve zeolitic imidazolate frameworks (ZIFs; termed ZIF-1 to -12) have been synthesized as crystals by copolymerization of either Zn(II) (ZIF-1 to -4, -6 to -8, and -10 to -11) or Co(II) (ZIF-9 and -12) with imidazolate-type links. The ZIF crystal structures are based on the nets of seven distinct aluminosilicate zeo...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.0602439103
更新日期:2006-07-05 00:00:00
abstract::In mantle cell lymphoma (MCL), the translocation t(11;14) is considered the cytogenetic hallmark of the disease. Recently, however, deletion of the chromosomal region 11q22-q23 has been identified as a frequent event in this type of cancer, indicating the existence of a pathogenically relevant tumor suppressor gene in...
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pub_type: 杂志文章
doi:10.1073/pnas.050400997
更新日期:2000-03-14 00:00:00
abstract::In North America there are two generally recognized pathotypes (pathotypes 1 and 2) of the fungus Entomophaga grylli which show host-preferential infection of grasshopper subfamilies. Pathotype 3, discovered in Australia, has a broader grasshopper host range and was considered to be a good biocontrol agent. Between 19...
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.93.2.918
更新日期:1996-01-23 00:00:00
abstract::MicroRNAs (miRNAs) are endogenously encoded small noncoding RNAs, derived by processing of short RNA hairpins, that can inhibit the translation of mRNAs bearing partially complementary target sequences. In contrast, small interfering RNAs (siRNAs), which are derived by processing of long double-stranded RNAs and are o...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.1630797100
更新日期:2003-08-19 00:00:00
abstract::The advent of molecular tension probes for real-time mapping of piconewton forces in living systems has had a major impact on mechanobiology. For example, DNA-based tension probes have revealed roles for mechanics in platelet, B cell, T cell, and fibroblast function. Nonetheless, imaging short-lived forces transmitted...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2019-08-20 00:00:00
abstract::Efficient and reliable classification of visual stimuli requires that their representations reside a low-dimensional and, therefore, computationally manageable feature space. We investigated the ability of the human visual system to derive such representations from the sensory input-a highly nontrivial task, given the...
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.93.21.12046
更新日期:1996-10-15 00:00:00
abstract::Laser-induced fluorescence at 337-nm excitation was used in vivo to differentiate neoplastic [cervical intraepithelial neoplasia (CIN)], nonneoplastic abnormal (inflammation and human papilloma viral infection), and normal cervical tissues. A colposcope (low-magnification microscope used to view the cervix with reflec...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 临床试验,杂志文章
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abstract::The protooncogene c-fps/fes is a single vertebrate locus homologous to both the fps transforming gene of Fujinami avian sarcoma virus and the fes transforming gene of two feline sarcoma virus isolates. The human c-fps/fes locus has been previously cloned and characterized. We report that a recombinant gene in which 3'...
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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:2007-10-02 00:00:00
abstract::Pathogenic retroviruses have evolved multiple means for evading host restriction factors such as apolipoprotein B editing complex (APOBEC3) proteins. Here, we show that murine leukemia virus (MLV) has a unique means of counteracting APOBEC3 and other cytosolic sensors of viral nucleic acid. Using virus isolated from i...
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.1217399110
更新日期:2013-05-28 00:00:00
abstract::In rats fed the liver carcinogen 2-acetylaminofluorene (AAF), the two most abundant types of DNA adduct are N-(deoxyguanosin-8-yl)-2-acetylaminofluorene and its deacetylated derivative. When plasmids carrying AAF adducts replicate in bacteria, the predominant mutations are frameshifts, whereas with deacetylated (AF) a...
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:1991-11-15 00:00:00
abstract::When spores of the anaerobic bacterium Clostridium novyi-NT are systemically injected into animals, they germinate exclusively within the hypoxic regions of cancers. The germinated bacteria destroy adjacent tumor cells but spare a rim of well oxygenated tumor cells that subsequently expand. Surprisingly, we found that...
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.0406242101
更新日期:2004-10-19 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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更新日期:2015-04-28 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.89.11.5030
更新日期:1992-06-01 00:00:00
abstract::Since cdc48 mutants were isolated by the first genetic screens for cell division cycle (cdc) mutants in yeast, the requirement of the chaperone-like ATPase Cdc48/p97 during cell division has remained unclear. Here, we discover an unanticipated function for Caenorhabditis elegans CDC-48 in DNA replication linked to cel...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.0805944105
更新日期:2008-09-02 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::A significant improvement in molecular hydrogen uptake properties is revealed by our ab initio calculations for Li-decorated metal-organic framework 5. We have found that two Li atoms are strongly adsorbed on the surfaces of the six-carbon rings, one on each side, carrying a charge of +0.9e per Li atom. Each Li can cl...
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:2007-12-18 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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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:2010-06-22 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.91.15.6914
更新日期:1994-07-19 00:00:00
abstract::Gaseous HCl generated from a variety of sources is ubiquitous in both outdoor and indoor air. Oxides of nitrogen (NO(y)) are also globally distributed, because NO formed in combustion processes is oxidized to NO(2), HNO(3), N(2)O(5) and a variety of other nitrogen oxides during transport. Deposition of HCl and NO(y) o...
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:2009-08-18 00:00:00
abstract::We have postulated that the toxic neuropathies associated with neurofilament-filled axonal swellings have a common pathogenesis, the covalent crosslinking of neurofilaments during anterograde transport. The newly described gamma-diketone, 3,4-dimethyl-2,5-hexanedione (DMHD), is a more potent analogue of the toxic meta...
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.81.15.4979
更新日期:1984-08-01 00:00:00