Abstract:
:Pig citrate synthase (PCS) can be used as a model enzyme to gain some insight into the structural basis of protein thermostability. The thermal unfolding characteristics of the specific secondary structure elements within PCS were monitored in detail by following changes in its amide I band components. The result of our study indicates that PCS undergoes irreversible thermal denaturation. Detailed analysis reveals that the different secondary structures display a multistep transition with a major and a minor transition at different temperatures and a very small initial transition at the same temperature (30 degrees C). A plot of temperature-induced changes in (1)H-(2)H exchange, the decrease in the absorbance of the alpha-helical structures, and the increase in the absorbance of aggregated structures all have in common a multistep transition, the minor one centered at 45 degrees C and the major one around 59 degrees C. In contrast, a band that is tentatively assigned to loop structures displays these same minor and major transitions but at lower temperatures (39 and 52 degrees C, respectively). The transition, which occurs at 39-45 degrees C, is not associated with the appearance of aggregated structures. This transition may reflect a change in the tertiary structure of the protein. However, the final transition, which occurs at a higher temperature (52-59 degrees C), reflects unfolding and aggregation of the polypeptide chains. The Fourier transform infrared (FTIR) analysis suggests that PCS has a thermolabile region that unfolds first, some 7 degrees C below the main unfolding of the protein. We propose that this reflects the unfolding of the highly flexible loop segments, which in turn triggers the unfolding of the predominantly helical core structure of PCS.
journal_name
Biopolymersjournal_title
Biopolymersauthors
Severcan F,Haris PIdoi
10.1002/bip.10392subject
Has Abstractpub_date
2003-08-01 00:00:00pages
440-7issue
4eissn
0006-3525issn
1097-0282journal_volume
69pub_type
杂志文章相关文献
BIOPOLYMERS文献大全abstract::Molecular structures for parallel DNA and RNA double helices with Hoogsteen pairing are proposed for the first time. The DNA helices have sugars in the C2'-endo region and the phosphodiester conformations are (trans, gauche-), and the RNA helices have sugars in the C3'-endo region and the phosphodiester conformations ...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.360341202
更新日期:1994-12-01 00:00:00
abstract::The advent of kinetically controlled Native Chemical Ligation has permitted more efficient sequential Native Chemical Ligation reactions to take place in one pot where one or more of the peptide fragments contains an N-terminal cysteine residue and a C-terminal thioester. The reactivity of the thioester component can ...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.21473
更新日期:2010-01-01 00:00:00
abstract::This work concerns the aggregation properties of (Gly-Val-Gly-Val-Pro)(251) rec, a polypentapeptide reflecting a highly conserved repetitive unit of the bioelastomer, elastin. On raising the temperature of aqueous solutions above 25 degrees C, this polypeptide was already known to undergo concurrent conformational cha...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/1097-0282(200107)59:1<51::AID-BIP1005>3.0.
更新日期:2001-07-01 00:00:00
abstract::The ion atmosphere created by monovalent (Na(+) ) or divalent (Mg(2+) ) cations surrounding a B-form DNA duplex were examined using atomistic molecular dynamics (MD) simulations and the nonlinear Poisson-Boltzmann (PB) equation. The ion distributions predicted by the two methods were compared using plots of radial and...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.22461
更新日期:2014-08-01 00:00:00
abstract::For systems involving highly and oppositely charged proteins, electrostatic forces dominate association and contribute to biomolecular complex stability. Using experimental or theoretical alanine-scanning mutagenesis, it is possible to elucidate the contribution of individual ionizable amino acids to protein associati...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.21644
更新日期:2011-11-01 00:00:00
abstract::The presence of low pKa N-hydroxylamines is beneficial in peptide chemistry as they reduce some base-mediated side reactions. Here we evaluated the applicability and buffering capacity of Ethyl 2-cyano-2-(hydroxyimino) acetate (Oxyma) in the prevention of aspartimide/piperidide formation and Pro-based overcoupling and...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.21713
更新日期:2012-01-01 00:00:00
abstract::The second derivative FTIR study of heat-induced and pressure-assisted cold-induced changes in the secondary structure of bovine alpha-lactalbumin was carried out for native holoprotein and calcium ion depleted apoprotein. The secondary structure and compactness of alpha-lactalbumin were examined in a temperature rang...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/1097-0282(2001)62:1<29::AID-BIP50>3.0.CO;2
更新日期:2001-01-01 00:00:00
abstract::The study of biologically active peptides is critical to the understanding of physiological pathways, especially those involved in the development of disease. Historically, the measurement of biologically active endogenous peptides has been undertaken by radioimmunoassay, a highly sensitive and robust technique that p...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.22109
更新日期:2012-01-01 00:00:00
abstract::The formation of the KRas4B-PDEδ complex activates different signaling pathways required for the development and maintenance of cancer. Previous experimental and theoretical studies have allowed researchers to design an inhibitor of the KRas4B-PDEδ complex, "Deltarasin." This inhibitor binds to the prenyl-binding pock...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.23333
更新日期:2019-11-01 00:00:00
abstract::Experimental and computational methods of infrared microspectroscopy (IRI-MSP) and infrared spectral mapping (ISM) are presented. These methods are subsequently applied to the analysis of cirrhotic liver tissue. The sensitivity of infrared spectral mapping toward spectral changes caused by disease will be demonstrated...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/1097-0282(2000)57:5<282::AID-BIP50>3.0.CO;
更新日期:2000-01-01 00:00:00
abstract::The conformational preferences of blocked alanine dipeptide (ADP), Ac-Ala-NHMe, in aqueous solution were studied using vibrational circular dichroism (VCD) together with density functional theory (DFT) calculations. DFT calculations of three most representative conformations of ADP surrounded by six explicit water mol...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.22460
更新日期:2014-07-01 00:00:00
abstract::Fluorescein-labeled antibodies are widely used in clinical assays and fluorescence microscopy. The fluorescent signal per labeled antibody is limited by fluorescein self-quenching, which occurs when the antibody is heavily labeled with multiple fluoresceins. We examined immunoglobulin G (IgG) when labeled with 0.7 to ...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.20098
更新日期:2004-08-15 00:00:00
abstract::The association behavior of beta-lactoglobulin has been studied by small-angle neutron scattering as a function of protein concentration, temperature, pH, and NaCl concentration of the solution. By indirect Fourier transformation of the spectra, pair-distance distribution functions for the various samples were obtaine...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/(SICI)1097-0282(199901)49:1<11::AID-BIP2>3
更新日期:1999-01-01 00:00:00
abstract::A new series of oxy-peptide nucleic acids (pyrrolidine-based oxy-peptide nucleic acids = POPNAs) of four different stereoisomeric forms (cis-L, cis-D, trans-L, trans-D) have been synthesized. To find a favorable stereoisomer of POPNA for hybridization with DNA or RNA, thermodynamic parameters and conformations of the ...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.20364
更新日期:2006-01-01 00:00:00
abstract::Collagen is a natural protein, which is used as a vital biomaterial in tissue engineering. The major concern about native collagen is lack of its thermal stability and weak resistance to proteolytic degradation. In this scenario, the crosslinking compounds used for stabilization of collagen are mostly of chemical natu...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.22473
更新日期:2014-08-01 00:00:00
abstract::An electron paramagnetic resonance (EPR) study was performed for potato and wheat starch containing Cu2+ ions as a paramagnetic probe. Distribution of water in the starch granules as well as the interactions between the copper and starch matrix of different crystalline structures were determined. EPR spectra of the na...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.20504
更新日期:2006-08-15 00:00:00
abstract::The visual pigment rhodopsin has been extensively studied for the kinetics of its photointermediates by various spectroscopic methods. Unlike such archaeal retinal proteins as bacteriorhodopsin, visual rhodopsin does not thermally recover its dark state after photoexcitation, which precludes repeated excitation of a s...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.20540
更新日期:2006-10-05 00:00:00
abstract::Conformational analysis of the neurohypophyseal hormones oxytocin (OT) and arginine-vasopressin (AVP) has been carried out using two different computational approaches and three force fields, namely by the Electrostatically Driven Monte Carlo (EDMC) method, with the Empirical Conformational Energy Program for Peptides...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/(sici)1097-0282(199602)38:2<157::aid-bip3>
更新日期:1996-02-01 00:00:00
abstract::A model of protein-chaperone interaction as a two-phase (unfolding/refolding) iterative annealing mechanism able to promote structural segregation of hydrophobic and hydrophilic monomers and thereby facilitate access to nativelike states has recently been applied successfully to two 22-mers of the Honeycutt and Thirum...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.10148
更新日期:2002-07-15 00:00:00
abstract::We report on the conformation of a tetrasaccharide fragment in the repeating subunit of the cell wall polysaccharide of Streptococcus mitis J22, a receptor for the lectin of Actinomyces viscosus T14V in a bacterial coaggregation that is important in the ecological interactions of oral bacteria. Although there is consi...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/(SICI)1097-0282(199603)38:3%3C339::AID-BIP
更新日期:1996-03-01 00:00:00
abstract::We have utilized a de novo designed two-stranded α-helical coiled-coil template to display conserved α-helical epitopes from the stem region of hemagglutinin (HA) glycoproteins of influenza A. The immunogens have all the surface-exposed residues of the native α-helix in the native HA protein of interest displayed on t...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.22808
更新日期:2016-03-01 00:00:00
abstract::Myelopeptides (MPs) are bioregulatory mediators of bone marrow origin. Several individual MPs have been isolated from the supernatant of porcine bone marrow cell culture by successive solid phase extraction and reversed-phase high performance liquid chromatography. Two of them, MP-1 (Phe-Leu-Gly-Phe-Pro-Thr) and MP-2 ...
journal_title:Biopolymers
pub_type: 杂志文章,评审
doi:10.1002/(SICI)1097-0282(1997)43:2<139::AID-BIP7>3.
更新日期:1997-01-01 00:00:00
abstract::Synthetic RNA poly[r(A-T)] has been synthesized and its CD spectral properties compared to those of poly[r(A-U)], poly[d(A-T)], and poly[d(A-U)] in various salt and ethanolic solutions. The CD spectra of poly[r(A-T)] in an aqueous buffer and of poly[d(A-T)] in 70.8% v/v ethanol are very similar, suggesting that they b...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.360290210
更新日期:1990-02-05 00:00:00
abstract::Vibrational spectroscopy coupled with thermogravimetry (TG) and differential scanning calorimetry (DSC) was used to characterize racemic propanoic acid, 2-methyl-5,6,7,8-tetrahydro-6-(methylamino)-1,2-naphthalenediyl ester hydrochloride (CHF-1035), which is a new DA2 dopaminergic receptor/alpha2 agonist and beta block...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.10089
更新日期:2002-01-01 00:00:00
abstract::Piscidin 1 (Pis-1) has a high broad-spectrum activity against bacteria, fungi, and viruses but it also has a moderate hemolytic activities. To improve the antibacterial activity and to reduce toxicity, mutants Pis-1AA (G8A/G13A double mutant) and Pis-1PG (G8P mutant) have been designed based on the crystal structure o...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.22116
更新日期:2012-12-01 00:00:00
abstract::Side-chain lactam bridges linking amino acid residues that are spaced several residues apart in the linear sequence offer a convenient and flexible method for introducing conformational constraints into a peptide structure. The availability of a variety of selectively cleavable protecting groups for amines and carboxy...
journal_title:Biopolymers
pub_type: 杂志文章,评审
doi:10.1002/bip.10203
更新日期:2002-01-01 00:00:00
abstract::The comprehensive understanding of disassembly mechanism of amyloid fibrils requires nano-scale characterization of the mechanical properties of amyloid fibrils during the disassembly process. In this work, gemini surfactant C12 C6 C12 Br2 micelles were used as a probe to disassemble Aβ(1-40) fibrils. The microstructu...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.22992
更新日期:2017-02-01 00:00:00
abstract::We studied fluorescence enhancements of fluorescein tethered to silver colloids of different size. Thiolated 23-mer oligonucleotide (ss DNA-SH) was bound selectively to silver colloids deposited on 3-aminopropyltriethoxysilane (APS)-treated quartz slides. Fluorescein-labeled complementary oligonucleotide (ss Fl-DNA) w...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.20179
更新日期:2005-01-01 00:00:00
abstract::Amidated kyotorphin (L-Tyr-L-Arg-NH2; KTP-NH2) causes analgesia when systemically administered. The lipophilic ibuprofen-conjugated derivative of KTP-NH2 has improved analgesic efficacy. However, fast degradation by peptidases impacts negatively in the pharmacodynamics of these drugs. In this work, selected derivative...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.22580
更新日期:2015-01-01 00:00:00
abstract::The comprehensive structural analysis reported herein of eight N-glycopeptides, in three different solvents, is based on quantitative CD experiments, homonuclear nuclear Overhauser effect measurements, and molecular dynamics (MD) calculations. Although several orientations of the two amide planes attached to the carbo...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.360330416
更新日期:1993-04-01 00:00:00