Abstract:
:A procedure for combined sequential affinity adsorption-electrophoresis has been devised. Its use for the rapid purification of a calcium-dependent cyclic nucleotide phosphodiesterase from bovine brain in high yield is described. In this procedure, proteins bound to a solid phase of calcium-dependent regulatory protein (CDR) linked to Sepharose 4B were electrophoretically eluted, concentrated, and separated, thus avoiding the large losses in activity incurred during attempts to purify further the phosphodiesterase eluted by conventional means. The highly purified phosphodiesterase prepared by this method was stable for months at -60 degrees C in the presence of glycerol. It has a higher affinity for cyclic GMP than for cyclic AMP, and hydrolysis of both substrates is stimulated 5- to 6-fold by calcium plus CDR. Factors that influence adsorption of the enzyme to CDR-Sepharose and selection of optimal conditions for electrophoresis were investigated. Sequential adsorption-electrophoresis should be generally useful in the purification of macromolecules for which affinity adsorbents are available. The procedures described here could be directly applicable to the purification of proteins that, like the phosphodiesterase, interact with CDR.
journal_name
Proc Natl Acad Sci U S Aauthors
Kincaid RL,Vaughan Mdoi
10.1073/pnas.76.10.4903subject
Has Abstractpub_date
1979-10-01 00:00:00pages
4903-7issue
10eissn
0027-8424issn
1091-6490journal_volume
76pub_type
杂志文章abstract::It has recently been demonstrated that coupled enzymatic processes may possess, for a particular choice of the state variables, multidimensional inflection points in thermodynamic force-flow space. The conditions for reciprocity in the linear region near such a reference state, which may be far from equilibrium, are o...
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.78.7.4314
更新日期:1981-07-01 00:00:00
abstract::A set of at least 30 proteins disappears from the two-dimensional electrophoretic pattern of human lymphoid cells treated with various antimitochondrial agents. This set is similar to the set of proteins found in isolated mitochondria (except for the presence of action in the latter group), indicating that the inhibit...
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.78.4.2407
更新日期:1981-04-01 00:00:00
abstract::Secretions of the uterus support survival and growth of the conceptus (embryo/fetus and associated membranes) during pregnancy. Galectin-15, also known as OVGAL11 and a previously uncharacterized member of the galectin family of secreted beta-galactoside lectins containing a conserved carbohydrate recognition domain 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.0402669101
更新日期:2004-05-25 00:00:00
abstract::Gene delivery to the central nervous system is central to the development of gene therapy for neurological diseases. We developed a baculovirus-derived vector, the Bac-CMV-GFP vector, containing a reporter gene encoding for the green fluorescent protein (GFP) under the control of the cytomegalovirus (CMV) promoter. Tw...
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.260472897
更新日期:2000-12-19 00:00:00
abstract::The CuAAC reaction (click chemistry) has been used in conjunction with solid-phase synthesis to produce catalytically active hairpin ribozymes around 100 nucleotides in length. Cross-strand ligation through neighboring nucleobases was successful in covalently linking presynthesized RNA strands with high efficiency (tr...
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.1006447107
更新日期:2010-08-31 00:00:00
abstract::Two monoclonal antibodies directed against the native beta 2 subunit of Escherichia coli tryptophan synthase [L-serine hydro-lyase (adding indoleglycerol-phosphate), EC 4.2.1.20], one recognizing the C-terminal F1 domain and the other the N-terminal F2 domain, were used to detect immunoreactive intermediates in the fo...
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.84.5.1147
更新日期:1987-03-01 00:00:00
abstract::Arsenic poisoning affects millions of people worldwide. Human arsenic intake from rice consumption can be substantial because rice is particularly efficient in assimilating arsenic from paddy soils, although the mechanism has not been elucidated. Here we report that two different types of transporters mediate transpor...
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.0802361105
更新日期:2008-07-22 00:00:00
abstract::The oligomerization of activated D- and L- and racemic guanosine-5'-phosphoro-2-methylimidazole on short templates containing D- and L-deoxycytidylate has been studied. Results obtained with D-oligo(dC)s as templates are similar to those previously reported for experiments with a poly(C) template. When one L-dC or two...
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.95.23.13448
更新日期:1998-11-10 00:00:00
abstract::Understanding the genetic networks that operate inside cells will require the dissection of interactions among network members. Here we describe a peptide aptamer isolated from a combinatorial library that distinguishes among such interactions. This aptamer binds to cyclin-dependent kinase 2 (Cdk2) and inhibits its ki...
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.95.24.14272
更新日期:1998-11-24 00:00:00
abstract::Immune function is an energetically costly physiological activity that potentially diverts calories away from less immediately essential life tasks. Among developing organisms, the allocation of energy toward immune function may lead to tradeoffs with physical growth, particularly in high-pathogen, low-resource enviro...
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,多中心研究
doi:10.1073/pnas.1717522115
更新日期:2018-04-24 00:00:00
abstract::Brain function depends on adaptive self-organization of large-scale neural assemblies, but little is known about quantitative network parameters governing these processes in humans. Here, we describe the topology and synchronizability of frequency-specific brain functional networks using wavelet decomposition of magne...
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.0606005103
更新日期:2006-12-19 00:00:00
abstract::The biological significance of DNA amplification in cancer is thought to be due to the selection of increased expression of a single or few important genes. However, systematic surveys of the copy number and expression of all genes within an amplified region of the genome have not been performed. Here we have used a 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.091582298
更新日期:2001-05-08 00:00:00
abstract::Swainsonine, an indolizidine alkaloid, inhibits the processing of asparagine-linked glycoproteins in both cell-free extracts and animal cells in culture. Thus, in a liver particulate enzyme preparation, swainsonine at 0.1-1.0 microM inhibited the mannosidase that releases [3H]mannose from a high mannose glycopeptide b...
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.78.12.7393
更新日期:1981-12-01 00:00:00
abstract::Molecular chaperones are an essential part of the machinery that avoids protein aggregation and misfolding in vivo. However, understanding the molecular basis of how chaperones prevent such undesirable interactions requires the conformational changes within substrate proteins to be probed during chaperone action. Here...
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.1407086111
更新日期:2014-09-16 00:00:00
abstract::Complex II inhibitors 3-nitropropionic acid (3NP) and malonate cause striatal damage reminiscent of Huntington's disease and have been shown to involve oxidative stress in their pathogenesis. Because nuclear factor erythroid 2-related factor 2 (Nrf2)-dependent transcriptional activation by means of the antioxidant res...
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.0408487101
更新日期:2005-01-04 00:00:00
abstract::We examined the ability of macrophages and B cells to function as antigen-presenting cells (APCs) for murine TH1 and TH2 cloned T helper cell lines. Antigen presented by concanavalin A-elicited peritoneal macrophages or resting splenic B cells stimulated antigen-dependent proliferation of both T helper subsets. Parafo...
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.85.21.8181
更新日期:1988-11-01 00:00:00
abstract::Epidermal growth factor (EGF) stimulates membrane protein phosphorylation in a human cell line, A-431. The known hepatic mitogenic action of EGF and the reduction in EGF receptor number that occurs during liver regeneration led us to study whether EGF-dependent protein kinase activity was present in rat liver and whet...
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.79.3.776
更新日期:1982-02-01 00:00:00
abstract::The Met mutant of Drosophila melanogaster is highly resistant to juvenile hormone III (JH III) or its chemical analog, methoprene, an insect growth regulator. Five major mechanisms of insecticide resistance were examined in Met and susceptible Met+ flies. These two strains showed only minor differences when penetratio...
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.87.6.2072
更新日期:1990-03-01 00:00:00
abstract::Respiratory cytochrome c has been found to be phosphorylated at tyrosine 97 in the postischemic brain upon neuroprotective insulin treatment, but how such posttranslational modification affects mitochondrial metabolism is unclear. Here, we report the structural features and functional behavior of a phosphomimetic cyto...
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.1806833115
更新日期:2018-07-31 00:00:00
abstract::The neutrality theory predicts that the rate of neutral molecular evolution is constant over time, and thus that there is a molecular clock for timing evolutionary events. It has been observed that the variance of the rate of evolution is generally larger than expected according to the neutrality theory, which has rai...
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.201392198
更新日期:2001-09-25 00:00:00
abstract::The immunoglobulin heavy-chain-associated tetrapeptide, tuftsin (Thr-Lys-Pro-Arg), known for its phagocytosis-stimulating activity, was found to augment the antigen-specific, macrophage-dependent education of T lymphocytes. The investigation of stereospecific characteristics of the tetrapeptide, by use of structural 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.75.7.3400
更新日期:1978-07-01 00:00:00
abstract::We determined the nucleotide sequence of about 1 kilobase of DNA 3' to the 5' long terminal repeat of three noninfectious ad one infectious proviral DNA clones of spleen necrosis virus, an avian retrovirus, to determine if the types of nucleic acid changes involved in retrovirus mutation shed light on special features...
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.79.4.1230
更新日期:1982-02-01 00:00:00
abstract::Helicobacter pylori VacA, a pore-forming toxin secreted by an autotransporter pathway, causes multiple alterations in human cells, contributes to the pathogenesis of peptic ulcer disease and gastric cancer, and is a candidate antigen for inclusion in an H. pylori vaccine. Here, we present a 2.4-A crystal structure 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.0707447104
更新日期:2007-10-09 00:00:00
abstract::Existing moral psychology research commonly explains certain phenomena in terms of a motivation to blame. However, this motivation is not measured directly, but rather is inferred from other measures, such as participants' judgments of an agent's blameworthiness. The present paper introduces new methods for assessing ...
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.1501592112
更新日期:2015-03-24 00:00:00
abstract::Aluminum (Al) is the most abundant metal in the Earth's crust, but its trivalent ionic form is highly toxic to all organisms at low concentrations. How Al enters cells has not been elucidated in any organisms. Herein, we report a transporter, Nrat1 (Nramp aluminum transporter 1), specific for trivalent Al ion in rice....
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.1004949107
更新日期:2010-10-26 00:00:00
abstract::An enconuclease activity that reacts with x-irradiated DNA is present in extracts of E. coli. By using centrifugal methods to monitor the conversion of the supercoiled, circular double-stranded DNA for phage phi-x-174 (replicative form) or PM2 to the relaxed circular form it was possible to quantitate the rate of radi...
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.72.6.1997
更新日期:1975-06-01 00:00:00
abstract::Experimental circular dichroic (CD) spectra of three proteins have been combined with estimates of the content of peptide-chain structural modes obtained from x-ray diffraction studies of the same proteins. Solution of the simultaneous equations at a series of wavelengths permits the construction of a CD spectrum for ...
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.68.5.969
更新日期:1971-05-01 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
pub_type: 杂志文章
doi:10.1073/pnas.0602439103
更新日期:2006-07-05 00:00:00
abstract::Glucagon-like peptide 1 (GLP-1) is a hormone derived from the preproglucagon molecule and is secreted by intestinal L cells. It is the most potent stimulator of glucose-induced insulin secretion and also suppresses in vivo acid secretion by gastric glands. A cDNA for the GLP-1 receptor was isolated by transient expres...
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.89.18.8641
更新日期:1992-09-15 00:00:00
abstract::Borrelia burgdorferi (Bb), the causative agent of Lyme disease, is transmitted to mammalian hosts through an arthropod (tick) vector. To establish infection, Bb must acquire essential nutrients, including transition metals, from its mammalian and tick hosts. Thus far, no metal transporter has been identified in Bb. He...
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.0812999106
更新日期:2009-03-03 00:00:00