Abstract:
:Apo-electron-transferring flavoprotein from pig kidney (apo-ETF) has been prepared by an acid ammonium sulfate procedure and reconstituted with FAD analogues to probe the flavin binding site. The 8-position of the bound flavin is accessible to solvent as judged by the reaction of 8-Cl-FAD-ETF with sodium sulfide and thiophenol. A series of 8-alkylmercapto-FAD analogues containing increasingly bulky substituents bind tightly to apo-ETF and can be reduced to the dihydroflavin level by octanoyl-CoA in the presence of catalytic levels of the medium-chain acyl-CoA dehydrogenase. Bulky substituents severely slow the rate of these interflavin electron-transfer reactions. In the case of the 8-cyclohexylmercapto derivative, this decrease reflects a sizable increase in the Km for ETF (approximately 14-fold) with only a 20% decrease in Vmax. Reduction of all of these 8-substituted derivatives involves the accumulation of ETF anion radical intermediates. Dihydro-5-deaza-FAD dehydrogenase, unlike the corresponding 1-deazaflavin substitution, is unable to reduce native ETF despite a strongly favorable redox potential difference. These results, together with data from the native proteins, are consistent with obligatory 1-electron transfer between dehydrogenase and ETF possibly involving the exposed dimethylbenzene edge of ETF. Irradiation of apo-ETF reconstituted with the photoaffinity analogue 8-azidoflavin leads to approximately 10% covalent incorporation of the flavin. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of apo-ETF labeled with tritiated 8-azido-FAD shows preferential labeling of the smaller subunit (88%, Mr 30,000 subunit; 12%, Mr 33,000 subunit).(ABSTRACT TRUNCATED AT 250 WORDS)
journal_name
Biochemistryjournal_title
Biochemistryauthors
Gorelick RJ,Thorpe Cdoi
10.1021/bi00370a050subject
Has Abstractpub_date
1986-11-04 00:00:00pages
7092-8issue
22eissn
0006-2960issn
1520-4995journal_volume
25pub_type
杂志文章相关文献
BIOCHEMISTRY文献大全abstract::Charybdotoxin (ChTX) and iberiotoxin (IbTX) are highly charged peptidyl toxins which exhibit 68% sequence identity and share a similar three-dimensional structure. Despite these structural similarities, IbTX and ChTX differ in their selectivity for two types of potassium channels; large conductance calcium-activated p...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00060a030
更新日期:1993-03-09 00:00:00
abstract::The physical origin of the extremely high thermal stability of tetraether liposomes composed of the polar lipid fraction E (PLFE) from the thermoacidophilic archaebacterium Sulfolobus acidocaldarius has been investigated. The leakage rate of trapped 5, 6-carboxyfluorescein (5(6)CF) and the proton permeability in PLFE ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi972163e
更新日期:1998-01-06 00:00:00
abstract::DNA sequences with homology to the major (A + T)-rich mouse satellite component were localized in CsCl gradients by hybridization with a labeled satellite cRNA probe. Although, as expected, most of the hybridization was to DNA in the satellite-rich shoulder, substantial radioactive cRNA hybridized with DNA from denser...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00518a025
更新日期:1981-07-21 00:00:00
abstract::The 2-thiocytidine residue at position 32 of tRNA1Arg from Escherichia coli was modified specifically with three photoaffinity reagents of different lengths, and the corresponding N-acetylarginyl-tRNA1Arg derivatives were cross-linked to the P site of E. coli 70S ribosomes by irradiation. Covalent attachment was depen...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00339a011
更新日期:1985-08-27 00:00:00
abstract::Reaction of poly(dA-[2'S-3H]dU) with activated bleomycin yields [3H]uracil propenal that completely retains the tritium label. In contrast, we have previously shown that reaction of poly(dA-[2'R-3H]dU) with activated bleomycin affords unlabeled uracil propenal [Wu, J. C., Kozarich, J. W., & Stubbe, J. (1983) J. Biol. ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00369a037
更新日期:1986-10-21 00:00:00
abstract::Cytochrome bc(1), a key enzyme of biological energy conversion, generates or uses a proton motive force through the Q cycle that operates within the two chains of cofactors that embed two catalytic quinone oxidation/reduction sites, the Q(o) site and the Q(i) site. The Q(o) site relies on the joint action of two cofac...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi801207f
更新日期:2008-11-25 00:00:00
abstract::By use of six highly purified exoglycosidases with well-defined specificity, the oligosaccharide units of human plasma beta 2-glycoprotein I (beta 2I) were modified by sequential enzymatic degradation. The released monosaccharides (NeuAc, Gal, GlcNAc, and Man) were quantified, and the carbohydrate compositions of the ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00478a020
更新日期:1990-07-03 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::CHO cells expressing the human insulin receptors (IR) were used to evaluate the effect of the potent farnesyltransferase inhibitor, manumycin, on insulin antiapoptotic function. Cell treatment with manumycin blocked insulin's ability to suppress pro-apoptotic caspase-3 activity which led to time-dependent proteolytic ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi000995y
更新日期:2000-10-17 00:00:00
abstract::The interactions of Alzheimer's amyloid beta-peptide with cyclodextrins were studied by (1)H NMR: the translational diffusion coefficient of the peptide and chemical shift changes were studied by the presence of variable concentrations of cyclodextrins. For the full-length peptide, Abeta(1-40), the combined results of...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi036254p
更新日期:2004-05-25 00:00:00
abstract::The three-dimensional structure of Aspergillus aculeatus beta-1,4-galactanase (AAGAL), an enzyme involved in pectin degradation, has been determined by multiple isomorphous replacement to 2.3 and 1.8 A resolution at 293 and 100 K, respectively. It represents the first known structure for a polysaccharidase with this s...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi026238c
更新日期:2002-12-24 00:00:00
abstract::We have studied the Cu(II), Co(II), and Fe(III) complexes of the antineoplastic drug bleomycin by using electron spin--echo envelope spectroscopy. For all three complexes, nitrogen coordination of the metal ions is demonstrated. For the Cu(II)-- and Co(II)--drug complexes, we have been able to identify imidazole as a ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00509a045
更新日期:1981-03-17 00:00:00
abstract::Misfolded proteins in the endoplasmic reticulum (ER) are degraded by N-terminal threonine proteases within the 26S proteasome. Each protease is formed by an activated beta subunit, beta5/X, beta1/Y, or beta2/Z, that exhibits chymotrypsin-like, peptidylglutamyl-peptide hydrolyzing, or trypsin-like activity, respectivel...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi011322y
更新日期:2001-11-06 00:00:00
abstract::The binding of formate ion, a substrate for the peroxidatic reaction of catalase, has been investigated by magnetic resonance techniques. Comparative studies of formate binding to ferric myoglobin have also been performed. The nuclear magnetic relaxation (NMR) rate of formate and water protons is enhanced by the prese...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00688a023
更新日期:1975-08-26 00:00:00
abstract::Heparanase is a beta-D-endoglucuronidase that cleaves heparan sulfate (HS) and has been implicated in many important physiological and pathological processes, including tumor cell metastasis, angiogenesis, and leukocyte migration. We report herein the identification of active-site residues of human heparanase. Using P...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi002080p
更新日期:2000-12-26 00:00:00
abstract::Phospholipids and sterols play multiple roles in cells. In addition to establishing barriers between compartments, they also provide the matrix for assembly and function of a large variety of catalytic processes. Lipid composition is a highly regulated feature of biological membranes, yet its implications for membrane...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.8b00326
更新日期:2018-07-17 00:00:00
abstract::The contribution of backbone hydrogen bonds in alpha-helices to the overall stability of a protein has been examined experimentally by replacing several backbone amide linkages in alpha-helix 39-50 of T4 lysozyme with ester linkages. T4 lysozyme variants wherein the backbone amide bonds between residues Ser38 and Leu3...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi9707685
更新日期:1997-09-23 00:00:00
abstract::The generation of multiprotein complexes at receptors and adapter proteins is crucial for the activation of intracellular signaling pathways. In this study, we used multiple biochemical and biophysical methods to examine the binding properties of several SH2 and SH3 domain-containing signaling proteins as they interac...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0357311
更新日期:2004-04-13 00:00:00
abstract::Polyadenylated RNA was isolated from nuclei of cultured Drosophila cells, Schneider's line 2, and used as a template to synthesize a complementary DNA probe. Hybridization experiments were performed to study the relationship between nuclear and cytoplasmic RNA. About two-thirds of the nuclear polyadenylated RNA sequen...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00656a026
更新日期:1976-06-01 00:00:00
abstract::Peptides have important biomedical applications, but poor correlation between in vitro and in vivo activities can limit their development for clinical use. The ability to generate peptides and monitor their expression with new mass spectrometric methods and biological activities in vivo would be an advantage for the d...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.0c00600
更新日期:2020-09-15 00:00:00
abstract::Cyanide inhibits the CO oxidation activity of carbon monoxide dehydrogenase from Clostridium thermoaceticum by binding tightly to the form of the C-cluster yielding the gav = 1.82 signal (the C1.82 form). CN- dissociates and the enzyme reactivates upon addition of CO, CO2 plus dithionite, or CS2 plus dithionite. Dithi...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00195a011
更新日期:1994-07-26 00:00:00
abstract::Protocatechuate 3,4-dioxygenase (3,4-PCD) utilizes a ferric ion to catalyze the aromatic ring cleavage of 3,4-dihydroxybenzoate (PCA) by incorporation of both atoms of dioxygen to yield beta-carboxy-cis, cis-muconate. The crystal structures of the anaerobic 3,4-PCD.PCA complex, aerobic complexes with two heterocyclic ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi970469f
更新日期:1997-08-19 00:00:00
abstract::Several polypeptide toxins from sea anemones caused delayed inactivation of mammalian voltage-dependent sodium channels, resulting in a positive inotropic effect on the heart. Anthopleurin B (ApB), a toxin produced by the sea anemone Anthopleura xanthogrammica, is the most potent of all known anemone toxins. Previous ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi9528457
更新日期:1996-03-19 00:00:00
abstract::Deuterium magnetic resonance spectra (55.26 MHz) of cholesterol-3 alpha-d1 and epicholesterol-3 beta-d1 in dipalmitoylglycerophosphocholine (DPPC) liposomes were measured as a function of sterol-to-phospholipid ratio below (24 degrees C) and above (60 degrees C) the phase transition temperature of DPPC. From the quadr...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00353a017
更新日期:1986-03-11 00:00:00
abstract::Vertical fluctuations of the terminal methyl groups of stearic acid acyl chains toward the surface of dimyristoylphosphatidylcholine (DMPC) bilayers have been investigated by using spin-label electron-electron double-resonance ( ELDOR ) methodology. Spin-label pairs consisting of two populations of stearic acid spin-l...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00305a032
更新日期:1984-05-08 00:00:00
abstract::An in vitro system reconstituted with mouse liver polysome translation products was used to study the nature of polypeptide species imported into mitochondria from different mouse tissues such as liver, kidney, brain, and heart, as well as from Ehrlich ascites, Novikoff hepatoma, and Morris hepatoma 3924A tumor lines....
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00348a041
更新日期:1985-12-31 00:00:00
abstract::Lysophosphatidic acid (1-acyl-sn-glycero-3-phosphate or LPA) is a phospholipid mediator displaying numerous and widespread biological activities and thought to act via G-protein-coupled receptors. Here we have studied the effects on human platelets of a number of LPA analogues, including two enantiomers of both N-palm...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi9816756
更新日期:1999-06-29 00:00:00
abstract::The cytochrome aa3-type terminal quinol oxidase of Bacillus subtilis catalyzes the four-electron reduction of dioxygen to water. It resembles the aa3-type cytochrome-c oxidase in using heme A as its active-site chromophores but lacks the CuA center and the cytochrome-c oxidizing activity of the mitochondrial enzyme. W...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00156a027
更新日期:1992-10-20 00:00:00
abstract::We report two small molecule azobenzenesulfonamide probes, CAP1 and CAP2, capable of photomodulating the activity of carbonic anhydrase (CA) on demand. In the trans form, CAP azobenzene probes adopt a linear shape, making them suitable for occupying the CA active site and interacting with Zn2+, thereby inhibiting enzy...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.8b00947
更新日期:2019-01-08 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