Abstract:
:The utilization of the isoaccepting species of leucyl-tRNA in protein synthesis has been examined in E. coli. Two minor leucyl-tRNA species, isoacceptors tRNA3Leu and tRNA4Leu, are the predominant species found bound to ribosomes during exponential growth in minimal medium. In rich medium, an increased proportion of tRNA1Leu is found bound to ribosomes. One species, tRNA5Leu, is always absent from ribosomes. In a mutant strain in which normal tRNA3Leu and tRNA5Leu are reduced or absent, tRNA1Leu is a major ribosome-bound species in minimal medium. Protein synthesis in vitro with RNA from E. coli further suggests that tRNA5Leu is rarely used for total protein synthesis; however, this species is active with RNA from MS2 phage. We propose that tRNA1Leu can substitute for tRNA3Leu under rapid growth conditions, and that tRNA5Leu is used minimally in total protein synthesis.
journal_name
Proc Natl Acad Sci U S Aauthors
Holmes WM,Goldman E,Miner TA,Hatfield GWdoi
10.1073/pnas.74.4.1393subject
Has Abstractpub_date
1977-04-01 00:00:00pages
1393-7issue
4eissn
0027-8424issn
1091-6490journal_volume
74pub_type
杂志文章abstract::Across the Upper Missouri River Basin, the recent drought of 2000 to 2010, known as the "turn-of-the-century drought," was likely more severe than any in the instrumental record including the Dust Bowl drought. However, until now, adequate proxy records needed to better understand this event with regard to long-term v...
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.1916208117
更新日期:2020-05-26 00:00:00
abstract::I summarize recent computational and experimental work that addresses the inherent variability in the synaptic and intrinsic conductances in normal healthy brains and shows that multiple solutions (sets of parameters) can produce similar circuit performance. I then discuss a number of issues raised by this observation...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章,评审
doi:10.1073/pnas.1010674108
更新日期:2011-09-13 00:00:00
abstract::Current issues pertaining to theoretical simulations of materials, with a focus on systems of nanometer-scale dimensions, are discussed. The use of atomistic simulations as high-resolution numerical experiments, enabling and guiding formulation and testing of analytic theoretical descriptions, is demonstrated through ...
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.0408038102
更新日期:2005-05-10 00:00:00
abstract::A single, modified nucleoside in Escherichia coli tRNA, 6-(3-methyl-2-butenylamino)-2-methyl-thio-9-beta-D-ribofuranosylpurine, has been desulfurized with Raney nickel to afford its probable biosynthetic precursor. The limitations of the reaction at the nucleoside and tRNA levels and its lack of inhibition of the amin...
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.68.1.48
更新日期:1971-01-01 00:00:00
abstract::The question was addressed whether the risk of cancer of an individual in a heterogeneous population can be predicted on the basis of measurable biochemical and biological variables postulated to be associated with the process of chemical carcinogenesis. Using the skin tumor model with outbred male NMRI mice, the late...
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.92.13.5900
更新日期:1995-06-20 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
abstract::The gluconate (gnt) operon of Bacillus subtilis consists of four gnt genes; the second and third genes code for gluconate kinase (gluconokinase, EC 2.7.1.12) and gluconate permease, respectively. A fragment carrying the promoter of this operon (gnt promoter) and the first gene (gntR) was subcloned into a promoter prob...
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.84.13.4524
更新日期:1987-07-01 00:00:00
abstract::A G to T mutation has been observed at the third position of codon 249 of the p53 tumor-suppressor gene in over 50% of the hepatocellular carcinoma cases associated with high exposure to aflatoxin B(1) (AFB(1)). Hypotheses have been put forth that AFB(1), in concert with hepatitis B virus (HBV), may play a role in 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.102167699
更新日期:2002-05-14 00:00:00
abstract::Interleukin (IL)-33 is an important member of the IL-1 family that has pleiotropic activities in innate and adaptive immune responses in host defense and disease. It signals through its ligand-binding primary receptor ST2 and IL-1 receptor accessory protein (IL-1RAcP), both of which are members of the IL-1 receptor fa...
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.1308651110
更新日期:2013-09-10 00:00:00
abstract::Turbulence is an important determinant of phytoplankton physiology, often leading to cell stress and damage. Turbulence affects phytoplankton migration both by transporting cells and by triggering switches in migratory behavior, whereby vertically migrating cells can actively invert their direction of migration upon e...
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.2005944118
更新日期:2021-02-02 00:00:00
abstract::Acid-sensing ion channels (ASICs) are neuronal non-voltage-gated cation channels that are activated when extracellular pH falls. They contribute to sensory function and nociception in the peripheral nervous system, and in the brain they contribute to synaptic plasticity and fear responses. Some of the physiologic cons...
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.0712280105
更新日期:2008-02-26 00:00:00
abstract::Human breast cancers contain an RNA related to that of mouse mammary tumor virus. In 79% of the breast malignancies examined, this type of RNA is a 70S-component encapsulated with RNA-instructed DNA polymerase in a particle possessing the density characteristics of RNA tumor viruses. Further, the DNA synthesized by th...
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.69.11.3133
更新日期:1972-11-01 00:00:00
abstract::Adenosine-to-inosine (A-to-I) RNA editing, catalyzed by ADAR enzymes, is a ubiquitous mechanism that generates transcriptomic diversity. This process is particularly important for proper neuronal function; however, little is known about how RNA editing is dynamically regulated between the many functionally distinct ne...
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.1811768116
更新日期:2019-02-05 00:00:00
abstract::Understanding how changes in antibiotic consumption affect the prevalence of antibiotic resistance in bacterial pathogens is important for public health. In a number of bacterial species, including Streptococcus pneumoniae, the prevalence of resistance has remained relatively stable despite prolonged selection pressur...
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.1617849114
更新日期:2017-01-31 00:00:00
abstract::Natural-abundance (13)C nuclear magnetic resonance spectra of ten common nucleotides in neutral, aqueous solutions have been determined and interpreted. The spectra of two of these substances were also determined in acidic solutions, and several of the carbon chemical shifts were found to depend markedly on pH. Within...
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.65.1.19
更新日期:1970-01-01 00:00:00
abstract::Exposure of human monocyte-macrophages to as little as 50 microliters of cultured medium from lymphocytes stimulated by concanavalin A (Con A) resulted in a dramatic decrease in the activities of the low density lipoprotein (LDL) receptor pathway, the LDL-dextran sulfate pathway, and the scavenger receptor pathway. Th...
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.79.3.922
更新日期:1982-02-01 00:00:00
abstract::Vertebrate hearing and balance are based in complex asymmetries of inner ear structure. Here, we identify retinoic acid (RA) as an extrinsic signal that acts directly on the ear rudiment to affect its compartmentalization along the anterior-posterior axis. A rostrocaudal wave of RA activity, generated by tissues surro...
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.1010547108
更新日期:2011-01-04 00:00:00
abstract::When the lactose (lac) permease of Escherichia coli is expressed from the lac promoter at relatively low rates, deletion of amino acid residues 2-8 (delta 7) or 2-9 (delta 8) from the hydrophilic N terminus has a relatively minor effect on the ability of the permease to catalyze active lactose transport. Activity is e...
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.89.8.3180
更新日期:1992-04-15 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.67.4.1727
更新日期:1970-12-01 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.241510698
更新日期:2001-11-20 00:00:00
abstract::A mutation in the Escherichia coli dsbA gene (coding for a periplasmic disulfide oxidoreductase) reduces the rate of disulfide bond formation in the enzyme pullulanase and also reduces the rate at which the enzyme is secreted to the cell surface, as measured by protease accessibility. The enzyme did not become proteas...
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.89.24.12058
更新日期:1992-12-15 00:00:00
abstract::A major barrier to transitions to environmental sustainability is that consumers lack information about the full environmental footprints of their purchases. Sellers' incentives do not support reducing the footprints unless customers have such information and are willing to act on it. We explore the potential of moder...
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.1522211113
更新日期:2016-08-30 00:00:00
abstract::The twin-arginine transport (Tat) system is a protein-targeting pathway of prokaryotes and chloroplasts. Most Escherichia coli Tat substrates are complex metalloenzymes that must be correctly folded and assembled before transport, and a preexport chaperone-mediated "proofreading" process is therefore in operation. 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.0500737102
更新日期:2005-06-14 00:00:00
abstract::Large quantities of mineral dust particles are frequently ejected into the atmosphere through the action of wind. The surface of dust particles acts as a sink for many gases, such as sulfur dioxide. It is well known that under most conditions, sulfur dioxide reacts on dust particle surfaces, leading to the production ...
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.1212297109
更新日期:2012-12-18 00:00:00
abstract::The double-stranded RNA (dsRNA)-dependent protein kinase (PKR) is induced as part of the IFN response in mammals and acts to shut down protein synthesis by the phosphorylation of eukaryotic initiation factor 2alpha (eIF2alpha). In fish, a PKR-like kinase activity has been detected, but the enzyme responsible has elude...
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.0408714102
更新日期:2005-02-01 00:00:00
abstract::mRNA coding for mouse major transplantation antigens of the d haplotype was partially purified, copied into double-stranded cDNA, and cloned in Escherichia coli. Clones were selected by their ability to hybridize specifically with mRNA coding for H-2K, D, or L antigens. One of these clones, pH-2d-1, carries a 1200-bas...
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.78.5.2772
更新日期:1981-05-01 00:00:00
abstract::Interphotoreceptor retinoid-binding protein (IRBP) has been hypothesized to function as an intercellular shuttle in the vertebrate eye, serving to transport retinoids between the retinal pigment epithelium (RPE) and photoreceptors in the process by which visual pigment is regenerated after photolysis. This hypothesis ...
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.87.17.6907
更新日期:1990-09-01 00:00:00
abstract::Transcription in the human immunodeficiency virus type 1 (HIV-1) retrovirus is regulated by binding the viral Tat protein (trans-acting transcriptional activator) to the trans-activation response (TAR) RNA sequence. Here, vacuum UV circular dichroism (VUV-CD) is used to study the structure of TAR and its complex with ...
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.89.20.9734
更新日期:1992-10-15 00:00:00
abstract::Emerging evidence suggests that tissue plasminogen activator (tPA), currently the only FDA-approved medication for ischemic stroke, exerts important biological actions on the CNS besides its well-known thrombolytic effect. In this study, we investigated the role of tPA on primary neurons in culture and on brain recove...
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.1821979116
更新日期:2019-04-30 00:00:00
abstract::We and others have reported that the vast majority of virus-producing CD4(+) T cells during the acute infection of rhesus macaques with simian immunodeficiency virus (SIV) or CXCR4 (X4)-using simian/human immunodeficiency viruses (SHIVs) exhibited a nonactivated phenotype. These findings have been extended to show tha...
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.0903022106
更新日期:2009-05-12 00:00:00