Abstract:
:The ligand-binding dynamics and the reaction with O(2) of the fully (five-electron) reduced cytochrome caa(3) from the thermohalophilic bacterium Rhodothermus (R.) marinus were investigated. The enzyme is a proton pump which has all the residues of the proton-transfer pathways found in the mitochondrial-like enzymes conserved, except for one of the key elements of the D-pathway, the helix-VI glutamate [Glu(I-286), R. sphaeroides numbering]. In contrast to what has been suggested previously as general characteristics of thermophilic enzymes, during formation of the R. marinus caa(3)-CO complex, CO binds weakly to Cu(B), and is rapidly (k(Ba) = 450 s(-1)) trapped by irreversible (K(Ba) = 4.5 x 10(3)) binding to heme a(3). Upon reaction of the fully reduced enzyme with O(2), four kinetic phases were resolved during the first 10 ms after initiation of the reaction. On the basis of a comparison to reactions observed with the bovine enzyme, these phases were attributed to the following transitions between intermediates (pH 7.8, 1 mM O(2)): R --> A (tau congruent with 8 micros), A --> P(r) (tau congruent with 35 micros), P(r) --> F (tau congruent with 240 micros), F --> O (tau congruent with 2.5 ms), where the last two phases were associated with proton uptake from the bulk solution. Oxidation of heme c was observed only during the last two reaction steps. The slower transition times as compared to those observed with the bovine enzyme most likely reflect the replacement of Glu(I-286) of the helix-VI motif -XGHPEV- by a tyrosine in the R. marinus enzyme in the motif -YSHPXV-. The presence of an additional, fifth electron in the enzyme was reflected by two additional kinetic phases with time constants of approximately 20 and approximately 720 ms during which the fifth electron reequilibrated within the enzyme.
journal_name
Biochemistryjournal_title
Biochemistryauthors
Sigurdson H,Namslauer A,Pereira MM,Teixeira M,Brzezinski Pdoi
10.1021/bi010344hsubject
Has Abstractpub_date
2001-09-04 00:00:00pages
10578-85issue
35eissn
0006-2960issn
1520-4995pii
bi010344hjournal_volume
40pub_type
杂志文章相关文献
BIOCHEMISTRY文献大全abstract::The thylakoid transmembrane DeltapH is the sole energy source driving translocation of precursor proteins by the DeltapH/Tat machinery. Consequently, proton translocation must be coupled to precursor translocation. For the precursor of the 17 kDa protein of the oxygen-evolving complex (pOE17), the protein translocatio...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi000115f
更新日期:2000-07-18 00:00:00
abstract::Corticosteroid binding globulin (CBG), a serum glycoprotein which binds glucocorticoids and progestins with high affinity, is widely distributed throughout the animal world. Although its charge and size characteristics have largely been conserved across species, we found the behavior of CBG in squirrel monkey (Saimiri...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00407a046
更新日期:1988-04-05 00:00:00
abstract::Ammonia is an inhibitor of water oxidation and a structural analogue for substrate water, making it a valuable probe for the structural properties of the possible substrate-binding site on the oxygen-evolving complex (OEC) in photosystem II (PSII). By using the NH(3)-induced upshift of the 1365 cm(-)(1) IR mode in the...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi050030k
更新日期:2005-07-19 00:00:00
abstract::We have used nucleoside phosphorothioates (NTP alpha S) and a substitution-interference method to identify phosphate oxygens that appear to be important to guanosine cofactor addition in the self-splicing group I intron from Tetrahymena thermophila. For the majority of these phosphate oxygens, however, the effect of N...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00068a001
更新日期:1993-05-04 00:00:00
abstract::Heme A, an obligatory cofactor in eukaryotic cytochrome c oxidase, is produced from heme B (protoheme) via two enzymatic reactions catalyzed by heme O synthase and heme A synthase. Heme O synthase is responsible for the addition of a farnesyl moiety, while heme A synthase catalyzes the oxidation of a methyl substituen...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0203536
更新日期:2002-09-10 00:00:00
abstract::The beta chain 15-42 sequence of the fibrin(ogen) E region was implicated in heparin binding [Odrljin et al. (1996) Blood 88, 2050-2061]; whether heparin binds to other fibrin(ogen) regions remains to be clarified. To address this question, we studied the interaction of heparin with fibrinogen, fibrin, and their major...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0344073
更新日期:2003-07-01 00:00:00
abstract::The growth and shortening of microtubules in guanosine triphosphate-(GTP-) mediated dynamic instability has previously been observed to occur at rates which are remarkably variable (Gildersleeve et al., 1992, Chrétien et al., 1995). Neighboring microtubules observed simultaneously can grow or shorten at different rate...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi961070e
更新日期:1996-11-12 00:00:00
abstract::Nonribosomal peptide synthetases (NRPSs) are megasynthetases that require complex and specific interactions between multiple domains and proteins to functionally produce a metabolite. MbtH-like proteins (MLPs) are integral components of many NRPSs and interact directly with the adenylation domain of the megasynthetase...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.8b00552
更新日期:2018-07-17 00:00:00
abstract::Uncontrolled proteolysis due to cathepsin G (cat G) may cause severe pathological disorders. Cat G is inhibited by alpha 1-antichymotrypsin (ACT) and alpha 1-proteinase inhibitor (alpha 1PI), two members of the serpin superfamily of proteins. To see whether these two inhibitors play a physiological proteolysis-prevent...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi980223q
更新日期:1998-08-11 00:00:00
abstract::Cholesterol and its hemisuccinate and sulfate derivatives are widely used in studies of purified membrane proteins but are difficult to solubilize in aqueous solution, even in the presence of detergent micelles. Other cholesterol derivatives do not form conventional micelles and lead to viscous solutions. To address t...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi101334j
更新日期:2010-11-09 00:00:00
abstract::Cholera toxin, an activator of adenylate cyclase in a wide variety of cells, is a substrate for the phosphotransferase reaction catalyzed by purified cyclic adenosine 5'-monophosphate dependent bovine cardiac muscle protein kinase and the protein associated with human erythrocyte membranes. Phosphorylation occurs when...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00658a031
更新日期:1976-06-29 00:00:00
abstract::MAP kinase kinase (MAPKK) is a dual specificity protein kinase that phosphorylates and activates MAP kinase in vivo. In this study, four mouse monoclonal single-chain Fv (scFv) antibodies (Y1-6, Y1-7, Y3-6, and Y3-11) that can specifically bind to Xenopus MAPKK were isolated from combinatorial scFv-displaying phage li...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi960956f
更新日期:1996-10-08 00:00:00
abstract::The infectious isoform of the prion protein (PrPSc) is derived from cellular PrP (PrPC) in a conversion reaction involving a dramatic reorganization of secondary and tertiary structure. While our understanding of the pathogenic role of PrPSc has grown, the normal physiologic function of PrPC still remains unclear. Usi...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi972827k
更新日期:1998-05-19 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::Botulinum neurotoxins (BoNTs) elicit flaccid paralysis through cleavage of SNARE proteins within peripheral neurons. There are seven serotypes of the BoNTs, termed A-G, which differ in the SNARE protein and/or site that is cleaved. BoNTs are single-chain toxins that comprise an N-terminal zinc metalloprotease domain t...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi602396x
更新日期:2007-03-20 00:00:00
abstract::Escherichia coli class Ib ribonucleotide reductase (RNR) converts nucleoside 5'-diphosphates to deoxynucleoside 5'-diphosphates in iron-limited and oxidative stress conditions. We have recently demonstrated in vitro that this RNR is active with both diferric-tyrosyl radical (Fe(III)(2)-Y(•)) and dimanganese(III)-Y(•) ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi101881d
更新日期:2011-03-15 00:00:00
abstract::The iron K-edge X-ray absorption spectrum of Rhodococcus sp. R312 (formerly Brevibacterium sp. R312) nitrile hydratase in frozen solutions at pH 7 and 9 has been analyzed to determine details of the iron coordination. EXAFS analysis implies two or three sulfur ligands per iron and overall six coordination; together wi...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi960164l
更新日期:1996-08-06 00:00:00
abstract::Sulfation is a Golgi-specific modification of secretory proteins. We have characterized the proteins that are labeled with 35SO4 in cultures of rat hepatocytes and studied their transport to the medium. Analysis by polyacrylamide gel electrophoresis showed that of the five most heavily labeled proteins, four had well-...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00435a069
更新日期:1989-05-02 00:00:00
abstract::Specificity of the binding of sterols and related compounds with purified F-protein (fusion protein) of the HVJ (Sendai virus) was studied by binding competition with [3H]cholesterol. Requirement for cholesterol or the A/B ring trans structure and nonrequirement for the 3-hydroxyl group were found in this binding. Bin...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00404a035
更新日期:1988-02-23 00:00:00
abstract::Tritiated sodium borohydride was used to reduce the substrates of triosephosphate isomerase in the presence of the enzyme, and the mixture of the four possible products (D-[1(R)-3H]; D-[1(S)-3H]-; D-[2-3H]-, and L-[2-3H]glycerol 3-phosphate) was analyzed. While enzyme-bound dihydroxyacetone phosphate is reduced comple...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00692a020
更新日期:1975-10-21 00:00:00
abstract::Two thiol-activated endopeptidases with pH optima near pH 7.5 were isolated from the supernatant fraction of rabbit brain homogenates by DEAE-cellulose chromatography, gel filtration and isoelectrofocusing. Peptide bond hydrolysis was measured quantitatively by ion-exchange chromatography with an amino acid analyzer. ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00654a026
更新日期:1976-05-04 00:00:00
abstract::A cutinase-type polyesterase from Saccharomonospora viridis AHK190 (Cut190) has been shown to degrade the inner block of polyethylene terephthalate. A unique feature of Cut190 is that its function and stability are regulated by Ca2+ binding. Our previous crystal structure analysis of Cut190S226P showed that one Ca2+ b...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.8b00624
更新日期:2018-09-11 00:00:00
abstract::Doxorubicin (DOX) is a chemotherapeutic that is used in the treatment of a wide variety of cancers. However, it causes cardiotoxicity partly because of the formation of reactive oxygen species. CYP2J2 is a human cytochrome P450 that is strongly expressed in cardiomyocytes. It converts arachidonic acid (AA) into four d...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.7b01025
更新日期:2017-12-26 00:00:00
abstract::Helicobacter pylori produces one monofunctional catalase, encoded by katA (hp0875). The crystal structure of H. pylori catalase (HPC) has been determined and refined at 1.6 A with crystallographic agreement factors R and R(free) of 17.4 and 21.9%, respectively. The crystal exhibits P2(1)2(1)2 space group symmetry and ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi035663i
更新日期:2004-03-23 00:00:00
abstract::Ribosomal protein E-L30 unfolds reversibly at pH values between 7.0 and 4.5. Unfolding of the protein involves a fast and a slow equilibrium, which depend on the degree of protonation of His19 and His33. Both the fast equilibrium between protonated and deprotonated histidines and the slow equilibrium between folded an...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00391a050
更新日期:1987-08-25 00:00:00
abstract::A double mutant cycle has been used to evaluate interaction energies between the global stabilizer mutation asparagine 52 --> isoleucine (N52I) in iso-1-cytochrome c and mutations producing single surface histidines at positions 26, 33, 39, 54, 73, 89, and 100. These histidine mutation sites are distributed through th...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi034958t
更新日期:2003-09-16 00:00:00
abstract::The complete amino acid sequence of a small, basic protein with cardiotoxic activity is described. This toxin, designated Naja naja F8, was isolated from the venom of Naja naja, of Cambodian origin, by gel filtration on Sephadex G-75 followed by gradient ion exchange chromatography on Bio-Rex 70. The cardiotoxin F8, m...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00684a011
更新日期:1975-07-01 00:00:00
abstract::The derivatives of calf thymus DNA in which n-butylamine is covalently attached as described in the preceding paper in this series [Chen, C. Y., Pheiffer, B. H., Zimmerman, S. B., & Hanlon, S. (1983) Biochemistry (preceding paper in this issue)] were examined by Raman spectroscopy. As previously mentioned, these compl...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00289a021
更新日期:1983-09-27 00:00:00
abstract::The selenoamino acids methylselenocysteine (MeSeCys) and selenomethionine (SeMet) have disparate efficacies as anticancer agents. Herein, we use X-ray absorption spectroscopy to determine the chemical form of selenium in human neuroblastoma cells. Cells treated with MeSeCys contain a significant diselenide component, ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi201462u
更新日期:2012-01-24 00:00:00
abstract::The circular dichroism (CD) of Pfl filamentous virus has been examined over the temperature range 0-40 degrees C, in the absence and presence of Hg(II), Ag(I), and Cu(II). Thermal difference CD spectra were obtained by subtraction of spectra recorded above and below a thermally induced structure transition near 12 deg...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00410a010
更新日期:1988-05-17 00:00:00