Abstract:
:Replacing Leu-182 by Ala in yeast alcohol dehydrogenase (YADH; alcohol:NAD+ oxidoreductase, EC 1.1.1.1) yields a mutant that retains 34% of its kcat value and makes one stereochemical "mistake" every 850,000 turnovers (instead of approximately 1 error every 7,000,000,000 turnovers in native YADH) in its selection of the 4-Re hydrogen of NADH. Half of the decrease in stereochemical fidelity comes from an increase in the rate of transfer of the 4-Si hydrogen of NADH. The mutant also accepts 5-methylnicotinamide adenine dinucleotide, a cofactor analog not accepted by native YADH. The stereospecificity of the mutant is lower still with analogs of NADH where the carboxamide group of the nicotinamide ring is replaced by groups with weaker hydrogen bonding potential. For example, with thio-NADH, the mutant enzyme makes 1 stereochemical "mistake" every 450 turnovers. Finally, the double mutant T157S/L182A, in which Thr-157 is replaced by Ser and Leu-182 is replaced by Ala, also shows decreased stereochemical fidelity. These results suggest that Si transfer in the mutant enzymes arises from NADH bound in a syn conformation in the active site and that this binding is not obstructed in native YADH by side chains essential for catalysis.
journal_name
Proc Natl Acad Sci U S Aauthors
Weinhold EG,Glasfeld A,Ellington AD,Benner SAdoi
10.1073/pnas.88.19.8420subject
Has Abstractpub_date
1991-10-01 00:00:00pages
8420-4issue
19eissn
0027-8424issn
1091-6490journal_volume
88pub_type
杂志文章abstract::Genes encoding thymidylate synthetase from Bacillus subtilis bacteriophages were cloned in Escherichia coli. Chimeric plasmids pCD1 and pCD3 were constructed from site-specific endonuclease digests of bacteriophage phi3T DNA cloned in pMB9 in E. coli. Similar cloning techniques with bacteriophage beta22 DNA yielded ch...
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.75.8.3664
更新日期:1978-08-01 00:00:00
abstract::The "kindling" phenomenon is associated with long-lasting facilitation of synaptic transmission. A possible mechanism of such facilitation could involve changes in the number of synaptic contacts. However, previous attempts to demonstrate a synaptic morphological alteration that could account for the long-term effects...
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.85.9.3260
更新日期:1988-05-01 00:00:00
abstract::The stability of an immunogen against enzymatic degradation is considered an important factor for the design of synthetic vaccines. For our studies, we have selected an epitope from the tandem-repeat unit of the high-molecular-weight MUC2 mucin glycoprotein, which can be underglycosylated in case of colon cancer. In t...
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.0407677102
更新日期:2005-01-11 00:00:00
abstract::Much discussion has occurred in recent years on whether observed patterns of structure in island bird communities are the result of competitive interactions among species or independent rates of colonization and extinction. Here two patterns of structure are presented for birds on 12 West Indian islands. Each of four ...
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.79.5.1563
更新日期:1982-03-01 00:00:00
abstract::During exercise, increased energy demands are met by increased glucose production that occurs simultaneously with the increased glucose uptake. We had previously observed that, during exercise, metabolic clearance rate of glucose (MCR) increases markedly in normal, but only marginally in poorly controlled diabetic dog...
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.88.4.1296
更新日期:1991-02-15 00:00:00
abstract::Androgen receptor (AR) target genes direct development and survival of the prostate epithelial lineage, including prostate cancer (PCa). Thus, endocrine therapies that inhibit the AR ligand-binding domain (LBD) are effective in treating PCa. AR transcriptional reactivation is central to resistance, as evidenced by 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.1308587110
更新日期:2013-10-22 00:00:00
abstract::The exocytosis of AMPA receptors is a key step in long-term potentiation (LTP), yet the timing and location of exocytosis and the signaling pathways involved in exocytosis during synaptic plasticity are not fully understood. Here we combine two-photon uncaging with two-photon imaging of a fluorescent label of surface ...
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.0913875107
更新日期:2010-09-07 00:00:00
abstract::To create a universal system for the control of gene expression, we have studied methods for the construction of novel polydactyl zinc finger proteins that recognize extended DNA sequences. Elsewhere we have described the generation of zinc finger domains recognizing sequences of the 5'-GNN-3' subset of a 64-member zi...
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.95.25.14628
更新日期:1998-12-08 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.88.4.1411
更新日期:1991-02-15 00:00:00
abstract::Activation of the MEK/ERK/Elk-signaling cascade is a mechanism for relaying mitogenic and stress stimuli for gene activation. MEK1 is the proximate kinase for activation of ERK1/2, and nuclear targeting of ERK1/2 is obligatory for Elk1 transcriptional activity. Human biliverdin reductase (hBVR) is a recently described...
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.0800750105
更新日期:2008-05-13 00:00:00
abstract::The high-affinity (K(m) = 3 x 10(-8) M) transport system for histidine in Salmonella typhimurium has been resolved into three components: J, K, and P. J, which is a histidine-binding protein released by osmotic shock, is specified by the hisJ gene: hisJ mutants lack the binding protein and are defective in histidine t...
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.66.4.1096
更新日期:1970-08-01 00:00:00
abstract::Vertebrate remains recovered from a limestone fissure filling on Antigua, Lesser Antilles, are associated with radiocarbon dates ranging from 4300 to 2500 yr B.P., contemporaneous with the earliest aboriginal human occupation of the island. Nine taxa of lizards, snakes, birds, bats, and rodents (one-third of the total...
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.81.14.4448
更新日期:1984-07-01 00:00:00
abstract::Biological membranes are complex, self-organized structures that define boundaries and compartmentalize space in living matter. Composed of a wide variety of lipid and protein molecules, these responsive surfaces mediate transmembrane signaling and material transport within the cell and with its environment. It is wel...
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.1014579108
更新日期:2011-04-26 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.0508081102
更新日期:2005-11-15 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.0511313103
更新日期:2006-07-05 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.1621301114
更新日期:2017-09-12 00:00:00
abstract::Glutaredoxins (Grxs) have been identified across taxa as important mediators in various physiological functions. A chloroplastic monothiol glutaredoxin, AtGRXS16 from Arabidopsis thaliana, comprises two distinct functional domains, an N-terminal domain (NTD) with GlyIleTyr-TyrIleGly (GIY-YIG) endonuclease motif and a ...
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.1306899110
更新日期:2013-06-04 00:00:00
abstract::We have examined the effect of diphtheria toxin, Pseudomonas aeruginosa exotoxin A, and cycloheximide on the CV-1 cell cytoskeleton. Within a few hours after producing an inhibition of cellular protein synthesis, all these agents specifically disrupted the organization of the vimentin filament system with no discernab...
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.77.12.7267
更新日期:1980-12-01 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
doi:10.1073/pnas.75.2.759
更新日期:1978-02-01 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
doi:10.1073/pnas.1012021107
更新日期:2010-09-28 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.85.20.7612
更新日期:1988-10-01 00:00:00
abstract::We have totally synthesized a gene that codes for rat hepatic cytochrome b5. The 5' flanking region was designed for efficient expression of this gene in Escherichia coli by incorporating an optimum ribosome binding site and spacer region. Both a soluble form, analogous to the protease-treated microsomal protein, as w...
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.83.24.9443
更新日期:1986-12-01 00:00:00
abstract::The development of seeds in flowering plants is placed under complex interactions between maternal tissues, the embryo, and the endosperm. The endosperm plays a major role in the regulation of seed size. In Arabidopsis thaliana, endosperm size depends on the coordination of the genetic pathway HAIKU (IKU) with epigene...
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.1305175110
更新日期:2013-09-17 00:00:00
abstract::We have noted consistent structural similarities among unrelated proteases. In comparison with other proteins of similar size, proteases have smaller than average surface areas, smaller radii of gyration, and higher C(alpha) densities. These findings imply that proteases are, as a group, more tightly packed than other...
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.070548997
更新日期:2000-04-11 00:00:00
abstract::Human craniofacial data were used to assess the similarities and differences between recent and prehistoric Old World samples, and between these samples and a similar representation of samples from the New World. The data were analyzed by the neighbor-joining clustering procedure, assisted by bootstrapping and by cano...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 历史文章,杂志文章
doi:10.1073/pnas.171305898
更新日期:2001-08-14 00:00:00
abstract::p63 inhibits metastasis. Here, we show that p63 (both TAp63 and ΔNp63 isoforms) regulates expression of miR-205 in prostate cancer (PCa) cells, and miR-205 is essential for the inhibitory effects of p63 on markers of epithelial-mesenchymal transition (EMT), such as ZEB1 and vimentin. Correspondingly, the inhibitory ef...
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.1110977109
更新日期:2012-09-18 00:00:00
abstract::Amphibians are a bellwether for environmental degradation, even in natural ecosystems such as Yellowstone National Park in the western United States, where species have been actively protected longer than anywhere else on Earth. We document that recent climatic warming and resultant wetland desiccation are causing sev...
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.0809090105
更新日期:2008-11-04 00:00:00
abstract::In this contribution, we study situations in which nanoparticles in a fluid are strongly heated, generating high heat fluxes. This situation is relevant to experiments in which a fluid is locally heated by using selective absorption of radiation by solid particles. We first study this situation for different types of ...
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.0901372106
更新日期:2009-09-08 00:00:00
abstract::A Jurassic salamander, Beiyanerpeton jianpingensis (gen. et sp. nov.), from a recently found site in western Liaoning Province, China is the earliest known record of Salamandroidea. As a Late Jurassic record of the group, it extends the range of the clade by ~40 Ma. The Late Jurassic taxon is neotenic and represented ...
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.1009828109
更新日期:2012-04-10 00:00:00
abstract::Pseudomonas fluorescens Pf-5, a rhizosphere-inhabiting bacterium that suppresses several soilborne pathogens of plants, produces the antibiotics pyrrolnitrin, pyoluteorin, and 2,4-diacetylphloroglucinol. A gene necessary for pyrrolnitrin production by Pf-5 was identified as rpoS, which encodes the stationary-phase sig...
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.92.26.12255
更新日期:1995-12-19 00:00:00