Abstract:
:Oxidation of low-density lipoprotein (LDL), the major cholesterol carrier in plasma, is thought to promote atherogenesis via several mechanisms. One proposed mechanism involves fusion of oxidized LDL in the arterial wall; another involves oxidation-induced amyloid formation by LDL apolipoprotein B. To test these mechanisms and to determine the effects of oxidation on the protein secondary structure and lipoprotein fusion in vitro, we analyzed LDL oxidized by nonenzymatic (Cu2+, H2O2, and HOCl) or enzymatic methods (myeloperoxidase/H2O2/Cl- and myeloperoxidase/H2O2/NO2-). Far-UV circular dichroism spectra showed that LDL oxidation induces partial unfolding of the secondary structure rather than folding into cross-beta amyloid conformation. This unfolding correlates with increased negative charge of oxidized LDL and with a moderate increase in thioflavin T fluorescence that may result from electrostatic attraction between the cationic dye and electronegative LDL rather than from dye binding to amyloid. These and other spectroscopic studies of low- and high-density lipoproteins, which encompass amyloid-promoting conditions (high protein concentrations, high temperatures, acidic pH), demonstrate that in vitro lipoprotein oxidation does not induce amyloid formation. Surprisingly, turbidity, near-UV circular dichroism, and electron microscopic data demonstrate that advanced oxidation inhibits heat-induced LDL fusion that is characteristic of native lipoproteins. Such fusion inhibition may result from the accumulation of anionic lipids and lysophospholipids on the particle surface and/or from protein cross-linking upon advanced lipoprotein oxidation. Consequently, oxidation alone may prevent rather than promote LDL fusion, suggesting that additional factors, such as albumin-mediated removal of lipid peroxidation products and/or LDL binding to arterial proteoglycans, facilitate fusion of oxidized LDL in vivo.
journal_name
Biochemistryjournal_title
Biochemistryauthors
Jayaraman S,Gantz DL,Gursky Odoi
10.1021/bi700225asubject
Has Abstractpub_date
2007-05-15 00:00:00pages
5790-7issue
19eissn
0006-2960issn
1520-4995journal_volume
46pub_type
杂志文章相关文献
BIOCHEMISTRY文献大全abstract::NMR spectroscopy and simulated annealing calculations have been used to determine the three-dimensional structure of RK-1, an antimicrobial peptide from rabbit kidney recently discovered from homology screening based on the distinctive physicochemical properties of the corticostatins/defensins. RK-1 consists of 32 res...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi000457l
更新日期:2000-12-26 00:00:00
abstract::Oligonucleotides labeled with hexachlorofluorescein (hex) have enabled the interaction of the restriction endonuclease EcoRV with DNA to be evaluated using fluorescence anisotropy. The sensitivity of hex allowed measurements at oligonucleotide concentrations as low as 1 nM, enabling K(D) values in the low nanomolar ra...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi001956p
更新日期:2001-02-27 00:00:00
abstract::Microtubules, ordinarily cold-labile structures, are made entirely resistant to cold temperature by the presence of substoichiometric amounts of STOP (stable tubule only polypeptide), a microtubule-associated protein. We have produced a monoclonal antibody which specifically recognizes a 145-kDa protein previously imp...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00428a064
更新日期:1989-01-24 00:00:00
abstract::The carboxyl-terminal region of factor IX (residues 403-415) contains several natural mutations which result in mild to severe forms of hemophilia B. A battery of factor IX minigene expression vectors carrying various mutations in the C-terminal region were constructed and studied by transient expression assay using H...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi962002v
更新日期:1997-04-08 00:00:00
abstract::Deletion of Glu146, Thr147, and Trp148 from thrombin dramatically alters its interactions with substrates, ligands, and inhibitors, and the changes appear to result from nonlocal modification of thrombin's structure [Le Bonniec, B. F., Guinto, E. R., & Esmon, C. T. (1992) J. Biol. Chem. 267, 19341-19348]. In an attemp...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00179a023
更新日期:1994-04-05 00:00:00
abstract::DNA cleavage by topoisomerase II in the absence or presence of mAMSA, and VM-26 was investigated in a series of oligonucleotides of 36 and 42 base pairs, which were derived from the DNA sequence of the major topoisomerase II cleavage site in the matrix-associated region of SV40 DNA. Topoisomerase II introduced strand ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00052a020
更新日期:1993-01-12 00:00:00
abstract::The highly conserved nature and tissue specificity of the seven vertebrate beta-tubulin isotypes provide circumstantial evidence that functional differences among isotypes may exist in vivo. Compelling evidence from studies of bovine brain beta-isotypes indicated significant conformational and functional differences i...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi972763d
更新日期:1998-03-31 00:00:00
abstract::Retinal rod and cone cGMP phosphodiesterases (PDE6 family) function as the effector enzyme in the vertebrate visual transduction cascade. The activity of PDE6 catalytic subunits is controlled by the Pgamma-subunits. In addition to the inhibition of cGMP hydrolysis at the catalytic sites, Pgamma is known to stimulate a...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi015935m
更新日期:2002-03-26 00:00:00
abstract::Beta2microglobulin (beta2m) is the major protein component of the fibrillar amyloid deposits isolated from patients diagnosed with dialysis-related amyloidosis (DRA). While investigating the molecular mechanism of amyloid fibril formation by beta2m, we found that the beta2m C-terminal peptide of 28 residues (cbeta2m) ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0301486
更新日期:2003-11-25 00:00:00
abstract::The neutron structure of subtilisin BPN' has been refined and analyzed at 2.0-A resolution. The structure studied was a mutant variant of subtilisin, Met222----Gln, and was used because large, uninhibited crystals could be grown, which was not the case for the native molecule. Comparison of the structure with that of ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00219a008
更新日期:1991-02-05 00:00:00
abstract::Single-molecule fluorescence resonance energy transfer (smFRET) methods were used to study the assembly pathway and DNA unwinding activity of the bacteriophage T4 helicase-primase (primosome) complex. The helicase substrates used were surface-immobilized model DNA replication forks "internally" labeled in the duplex r...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi400231s
更新日期:2013-05-07 00:00:00
abstract::Spectrophotometric titration of pyridoxamine-pyruvate transaminase (EC 2.6.1.30) with pyridoxal at pH 7.15 gives four equivalent binding sites per tetramer. The pH dependence of the equilibrium constant for the association of 5'-deoxypyridoxal with the active site lysine residue was determined spectrophotometrically. ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00643a013
更新日期:1977-11-29 00:00:00
abstract::Multimodular enzymes, including polyketide synthases (PKSs), nonribosomal peptide synthetases (NRPSs), and mixed PKS/NRPS systems, contain functional domains with similar functions. Domain swapping and module fusion are potential powerful strategies for creating hybrid enzymes to synthesize modified natural products. ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi047538s
更新日期:2005-03-29 00:00:00
abstract::Little is known about how a membrane can regulate interactions between transmembrane helices. Here, we show that strong self-interaction of the transmembrane helix of human quiescin sulfhydryl oxidase 2 rests on a motif of conserved amino acids comprising one face of the helix. Atomistic molecular dynamics simulations...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.5b01239
更新日期:2016-03-08 00:00:00
abstract::The bond cleavage step of pepsinogen activation has been investigated in a kinetic study in which the denatured products of short-term acidifications were separated on SDS-polyacrylamide gels and the peptide products were quantitated by densitometry. Although several peptide products were observed, under the condition...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00432a040
更新日期:1989-03-21 00:00:00
abstract::Bioluminescence with luciferase-luciferin pairs is an attractive method for surveying cells in live tissues and whole organisms. Recent advances in luciferin chemistry and luciferase engineering are further expanding the scope of the technology. It is now possible to spy on cells in a variety of deep tissues and visua...
journal_title:Biochemistry
pub_type: 杂志文章,评审
doi:10.1021/acs.biochem.7b00435
更新日期:2017-10-03 00:00:00
abstract::The binding of Zn2+ to tubulin and the ability of this cation to promote the polymorphic assembly of the protein were examined. Equilibrium binding showed the existence of more than 60 potential Zn2+ binding sites on the dimer, including a number of high-affinity sites. The number of high-affinity sites, estimated by ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00270a032
更新日期:1983-01-04 00:00:00
abstract::When stoichiometric amounts of tropomyosin (TM) are bound to F-actin in the presence of 2 mM ATP, the MG2+-activated acto-heavy meromyosin (HMM) ATPase is inhibited by about 60% in 5 mM MgCl2-30 mM KCl. If the concentration of MgCl2 is reduced to 1 mM, the inhibition disappears because TM no longer binds to F-actin. I...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00683a025
更新日期:1975-06-17 00:00:00
abstract::Steady-state kinetic parameters were determined for the human leukocyte elastase catalyzed hydrolysis of a series of peptide-based thiobenzyl esters and p-nitroanilides. The peptide units are MeOSuc-Val, MeOSuc-Alan-Pro-Val (n = 0-2), and MeOSuc-Alan-Pro-Ala (n = 1 or 2). The results of this study suggest five importa...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00379a015
更新日期:1987-03-10 00:00:00
abstract::Synaptotagmin I is the calcium sensor in synchronous neurotransmitter release caused by fusion of synaptic vesicles with the presynaptic membrane in neurons. Synaptotagmin I interacts with acidic phospholipids, but also with soluble N-ethylmaleimide-sensitive factor attachment receptors (SNAREs), at various stages in ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi101864k
更新日期:2011-04-05 00:00:00
abstract::Oligothymidylates covalently linked to iron-porphyrins were synthesized to target the nuclease activity of Fe-porphyrin to complementary polynucleotides. In the presence of oxygen and a reducing agent, oligo(dT)7 bearing the reactive group attached to the 3'-phosphate was shown to be active in the cleavage of poly(dA)...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00370a002
更新日期:1986-11-04 00:00:00
abstract::The relative activities of 313 mutants of the gene V protein of bacteriophage f1, assayed in vivo, have been used to evaluate two approaches to predicting the effects of single amino acid substitutions on the function of a protein. First, we tested methods that only depend on the properties of the wild-type and substi...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00239a022
更新日期:1991-06-25 00:00:00
abstract::The disulfide bond location of a homodimeric peptide, prothoracicotropic hormone (PTTH) of the silkworm, Bombyx mori, was determined by a combination of partial reduction and sequence analysis of peptide fragments generated through a partial reduction of PTTH followed by alkylation and enzyme digestion. The partial re...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00185a031
更新日期:1994-05-17 00:00:00
abstract::Prokaryotic promoters have been extensively studied to relate sequence features to promoter function. Here we examine the relationship between double-helix stability and promoter activity. The double-helix stability is evaluated from sequence data by free energy computation, based on reported values of dinucleotide fr...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00414a035
更新日期:1988-07-12 00:00:00
abstract::A general understanding of how cytochromes evolve within a fixed structure to optimize redox potential for specific bioenergetic processes does not exist. Toward this end, a library approach is used to investigate the range and distribution of redox potential which occurs when all sequence space available through muta...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0001675
更新日期:2000-05-23 00:00:00
abstract::We assigned l-talarate dehydratase (TalrD) and galactarate dehydratase (GalrD) functions to a group of orthologous proteins in the mechanistically diverse enolase superfamily, focusing our characterization on the protein encoded by the Salmonella typhimurium LT2 genome (GI:16766982; STM3697). Like the homologous mande...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi7008882
更新日期:2007-08-21 00:00:00
abstract::Hepatic microsomal cytochrome P-450 from phenobarbital-pretreated rats is destroyed by propyne in a reduced nicotinamide adenine dinucleotide dependent process which also results in vivo in the accumulation of an abnormal green porphyrin. The green porphyrin has been identified by its electronic absorption, mass spect...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00528a033
更新日期:1981-12-08 00:00:00
abstract::The fluorescence intensity of the two flavin prosthetic groups, FMN and FAD, in neuronal nitric oxide synthase (nNOS) was found to decay highly nonexponentially, being best described by four fluorescence lifetimes. This excited state heterogeneity is the result of multiple flavin quenching sites which are due to sever...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi981138l
更新日期:1998-12-15 00:00:00
abstract::Comparison of available sequences of HLA-A and HLA-B antigens shows that variable positions are predominantly localized in four segments spanning residues 63-85, 105-116, 138-156, and 177-194. The fourth segment is unique in that it contains no differences between antigens of the same locus. Secondary folding of HLA h...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00300a007
更新日期:1984-02-28 00:00:00
abstract::Polycyclic aromatic hydrocarbon (PAH)-DNA adducts pervert the execution or fidelity of enzymatic DNA transactions and cause mutations and cancer. Here, we examine the effects of intercalating PAH-DNA adducts on the religation reaction of vaccinia DNA topoisomerase, a prototypal type IB topoisomerase (TopIB), and the 3...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi060158h
更新日期:2006-06-20 00:00:00