Abstract:
:The electrical response of a pigmented lipid bilayer to a short laser pulse is measured by a tunable voltage clamp method. In this method, a variable access impedance permits "tuning" of the observed relaxations for optimal measurements. Analysis of the data so obtained leads to an equivalent circuit that contains a novel chemical capacitance charged by the specific photoreaction across a single membrane-water interface. This chemical capacitance is distinct from the ordinary membrane capacitance. The intrinsic chemical rate constant obtained from the equivalent circuit analysis is shown to be the pseudo-first-order rate constant of the reverse dark reaction of the reduced acceptor and the oxidized pigment. The tunable voltage clamp method of measurement and analysis allows unambiguous separation of this rate constant into resistive and capacitative elements, which are interpreted in molecular terms.
journal_name
Proc Natl Acad Sci U S Aauthors
Hong FT,Mauzerall Ddoi
10.1073/pnas.71.4.1564subject
Has Abstractpub_date
1974-04-01 00:00:00pages
1564-8issue
4eissn
0027-8424issn
1091-6490journal_volume
71pub_type
杂志文章abstract::Compartmentalization of proteins into subcellular organelles in eukaryotic cells is a fundamental mechanism of regulating complex cellular functions. Many proteins of Plasmodium falciparum merozoites involved in invasion are compartmentalized into apical organelles. We have identified a new merozoite organelle that co...
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.0709999104
更新日期:2007-12-11 00:00:00
abstract::The restoration of planar cell polarity is an essential but poorly understood step toward physiological recovery during sensory-organ regeneration. Investigating this issue in the lateral line of the zebrafish, we found that hair cells regenerate in pairs along a single axis established by the restricted localization ...
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.0608536103
更新日期:2006-12-05 00:00:00
abstract::Bacterial virulence factors are typically surface-associated or secreted molecules that in Gram-negative bacteria must cross the outer membrane (OM). Protein translocation across the bacterial OM is not well understood. To elucidate this process we studied P pilus biogenesis in Escherichia coli. We present high-resolu...
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.95.6.3146
更新日期:1998-03-17 00:00:00
abstract::Various reconstructive procedures have been attempted to restore a cosmetically acceptable phallus that would allow normal reproductive, sexual, and urinary function in patients requiring penile reconstruction. However, these procedures are limited by a shortage of native penile tissue. We previously demonstrated 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.0909367106
更新日期:2010-02-23 00:00:00
abstract::The mechanisms that cause aging are not well understood. The oxidative stress hypothesis proposes that the changes associated with aging are a consequence of random oxidative damage to biomolecules. We hypothesized that oxidation of specific proteins is critical in controlling the rate of the aging process. Utilizing ...
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.94.21.11168
更新日期:1997-10-14 00:00:00
abstract::Helicases are molecular motor enzymes that unwind and translocate nucleic acids. One of the central questions regarding helicase activity is whether the process of coupling ATP hydrolysis to DNA unwinding requires an oligomeric form of the enzyme. We have applied a pre-steady-state kinetics approach to address this qu...
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.232401899
更新日期:2002-11-12 00:00:00
abstract::The induction of hemoglobin synthesis by dimethylsulfoxide in cells infected with Friend leukemia virus has been shown to depend on the number of cell divisions after the addition of the inducing agent. In asynchronous cultures the cells have a generation time of 24 hr, and hemoglobin synthesis occurs after 48 hr 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.71.11.4551
更新日期:1974-11-01 00:00:00
abstract::Wild-type newborn mice are characterized by the ability of certain liver-specific genes encoding various enzymes and mapping on different chromosomes to respond to glucocorticoid induction. Newborn mice homozygous for deletions at and around the albino locus on chromosome 7 fail to develop this competence for hormone-...
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.88.13.5607
更新日期:1991-07-01 00:00:00
abstract::Germ-line mutations of tumor suppressor genes confer strong predisposition to tumor formation. In the rat, a form of dominantly inherited renal carcinoma (RC) results in multiple chromophobe cell tumors that resemble the human disease, and heterozygous carriers (RC/+) are highly susceptible to environmental agents (ra...
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.90.17.8038
更新日期:1993-09-01 00:00:00
abstract::The genes coding for apolipoproteins (apo) AI, CIII, and AIV, designated APOA1, APOC3, and APOA4, respectively, are closely linked and tandemly organized in the long arm of the human chromosome 11. A DNA rearrangement involving the genes encoding apoAI and apoCIII in certain patients with premature atherosclerosis has...
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.84.20.7198
更新日期:1987-10-01 00:00:00
abstract::The yeast SIN1 protein is a nuclear protein that together with other proteins behaves as a transcriptional repressor of a family of genes. In addition, sin1 mutants are defective in proper mitotic chromosome segregation. In an effort to understand the basis for these phenotypes, we employed the yeast two-hybrid system...
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.93.16.8274
更新日期:1996-08-06 00:00:00
abstract::In eukaryotes, ubiquitination is an important posttranslational process achieved through a cascade of ubiquitin-activating (E1), conjugating (E2), and ligase (E3) enzymes. Many pathogenic bacteria deliver virulence factors into the host cell that function as E3 ligases. How these bacterial "Trojan horses" integrate in...
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.1115025109
更新日期:2012-02-07 00:00:00
abstract::The recognition of carrier proteins by multiple catalytic partners occurs in every cycle of chain elongation in the biosynthesis of fatty acids and of the pharmacologically important polyketide and nonribosomal peptide natural products. To dissect the features of carrier proteins that determine specific recognition at...
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.0705122104
更新日期:2007-07-10 00:00:00
abstract::Radiation therapy is a widely used cancer treatment, but it causes side effects even when localized radiotherapy is used. Extensive apoptosis of microvascular endothelial cells of the lamina propria is the primary lesion initiating intestinal radiation damage after abdominal radiation therapy. Many in vitro studies su...
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.0307575101
更新日期:2004-04-13 00:00:00
abstract::The polyomavirus enhancer is composed of multiple DNA sequence elements serving as binding sites for proteins present in mouse nuclear extracts that activate transcription and DNA replication. We have identified three such proteins and their binding sites and correlate them with enhancer function. Mutation of nucleoti...
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.85.16.5839
更新日期:1988-08-01 00:00:00
abstract::The Escherichia coli flagellar motor senses the intracellular concentration of the response regulator CheY-P and responds by varying the bias between its counterclockwise (CCW) and clockwise (CW) rotational states. The response is ultrasensitive with a large Hill coefficient (approximately 10). Recently, the detailed ...
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.0804641105
更新日期:2008-08-19 00:00:00
abstract::We have examined the accumulation of newly synthesized nuclear proteins into nuclei during DNA repair synthesis in confluent WI-38 human diploid fibroblasts damaged with ultraviolet radiation or N-acetoxy-2-acetylaminofluroene. In contrast to a marked stimulation of DNA repair synthesis, stimulation of amino acid inco...
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.73.5.1466
更新日期:1976-05-01 00:00:00
abstract::The one-sided multipliers of an operator space X are a key to "latent operator algebraic structure" in X. We begin with a survey of these multipliers, together with several of the applications that they have had to operator algebras. We then describe several new results on one-sided multipliers, and new applications, ...
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.0305296101
更新日期:2004-01-20 00:00:00
abstract::Translational initiation factor 2 (IF2) is a guanine nucleotide-binding protein that can bind guanosine 3',5'-(bis) diphosphate (ppGpp), an alarmone involved in stringent response in bacteria. In cells growing under optimal conditions, the GTP concentration is very high, and that of ppGpp very low. However, under stre...
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.0606384103
更新日期:2006-09-19 00:00:00
abstract::Polyketides represent an extremely diverse class of secondary metabolites often explored for their bioactive traits. These molecules are also attractive building blocks for chemical catalysis and polymerization. However, the use of polyketides in larger scale chemistry applications is stymied by limited titers and yie...
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.1721203115
更新日期:2018-02-27 00:00:00
abstract::Cerebellar granule cells grown in the presence of a serum complex differentiate but are resistant to the lethal action of excitatory amino acids. When these cells are grown also in the presence of insulin-like growth factor I (IGF-I) they become fully susceptible to the toxic, lethal action of glutamate. The glutamate...
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.90.18.8752
更新日期:1993-09-15 00:00:00
abstract::d-amino acids are present in some peptides from amphibian skin. These residues are derived from the corresponding L-amino acids present in the respective precursors. From skin secretions of Bombinae, we have isolated an enzyme that catalyzes the isomerization of an L-Ile in position 2 of a model peptide to D-allo-Ile....
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.0500789102
更新日期:2005-03-22 00:00:00
abstract::Disease tolerance, the capacity of tissues to withstand damage caused by a stimulus without a decline in host fitness, varies across tissues, environmental conditions, and physiologic states. While disease tolerance is a known strategy of host defense, its role in noninfectious diseases has been understudied. Here, we...
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.2012003117
更新日期:2020-12-15 00:00:00
abstract::The neuropeptides oxytocin and vasopressin are evolutionarily conserved regulators of social perception and behavior. Evidence is building that they are critically involved in the development of social recognition skills within rodent species, primates, and humans. We investigated whether common polymorphisms in the g...
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.1302985111
更新日期:2014-02-04 00:00:00
abstract::T-regulatory cells (Treg) and mast cells (MC) are abundant in colorectal cancer (CRC) tumors. Interaction between the two is known to promote immune suppression or loss of Treg functions and autoimmunity. Here, we demonstrate that in both human CRC and murine polyposis the outcome of this interaction is the generation...
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.0913683107
更新日期:2010-04-06 00:00:00
abstract::Interleukin (IL)-15 and its specific receptor chain, IL-15Rα, support the development of various effector cells, including NK and CD8 T cells via a mechanism called trans-presentation. Whereas the dynamic of trans-presentation has been shown to involve the recycling of IL-15Rα by presenting cells, the way responding c...
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.1405514111
更新日期:2014-06-10 00:00:00
abstract::The transforming growth factors beta (TGF-beta s) are important modulators of growth and differentiation. They are intermolecular disulfide-bonded homodimeric molecules. The monomer fold has a conserved cystine knot and lacks a hydrophobic core. The biological specificity of a given member of the family is believed to...
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.92.12.5406
更新日期:1995-06-06 00:00:00
abstract::Five peptides corresponding to amino acid sequences predicted from all three reading frames of the nucleotide sequence of the third internal repeat array (IR3) of the Epstein-Barr virus (EBV) genome were synthesized chemically. All five peptides elicited antipeptide antibodies in rabbits. The antiserum raised against ...
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.81.15.4652
更新日期:1984-08-01 00:00:00
abstract::Na(+)-NQR is a unique respiratory enzyme that couples the free energy of electron transfer reactions to electrogenic pumping of sodium across the cell membrane. This enzyme is found in many marine and pathogenic bacteria where it plays an analogous role to the H(+)-pumping complex I. It has generally been assumed 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.1002866107
更新日期:2010-07-13 00:00:00
abstract::RNase T2 enzymes are conserved in most eukaryotic genomes, and expression patterns and phylogenetic analyses suggest that they may carry out an important housekeeping role. However, the nature of this role has been elusive. Here we show that RNS2, an intracellular RNase T2 from Arabidopsis thaliana, is essential for n...
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.1009809108
更新日期:2011-01-18 00:00:00