Abstract:
:When grown under O2-limited conditions, Escherichia coli expresses a cytochrome bd quinol oxidase that has an unusually high affinity for O2. We have studied the reaction of cytochrome bd with CO and O2 by rapid-reaction spectrophotometry. The reduced enzyme forms a photosensitive ferrocytochrome d-CO complex, and following photolysis, CO recombines with the reduced enzyme with a bimolecular rate of 8 x 10(7) M-1 s-1. Reaction of CO-bound enzyme with O2 gives a CO off-rate of 1.6 s-1. The O2 reaction is followed by a flow-flash procedure in which CO-ligated enzyme is mixed with O2, and the reaction commenced by photolysis of cytochrome d-CO. In the presence of O2, two processes are resolved on a time-scale of 300 microseconds. The absorbance at 645 nm first increases at a rate that is dependent on O2 concentration with a value of 2 x 10(9) M-1 s-1. The second phase results in decreased absorbance at 645 nm and increased absorbance at 680 nm. The rate of the second process is independent from O2 concentration above 50 microM O2 and reaches a first-order limit of 1 x 10(4) s-1. A model for the reaction of the cytochrome bd quinol oxidase with O2 is proposed in which an initial ferrocytochrome d-oxy adduct forms, and then decays to a ferryl-oxo species. The oxidation of the low-spin cytochrome b component of the oxidase, monitored at 560 nm, occurs at the same time as the ferryl species forms. We suggest that the suitability of the cytochrome bd quinol oxidase to function at low O2 concentration is conferred by its rapid rate of binding O2.
journal_name
Biochemistryjournal_title
Biochemistryauthors
Hill BC,Hill JJ,Gennis RBdoi
10.1021/bi00254a021subject
Has Abstractpub_date
1994-12-20 00:00:00pages
15110-5issue
50eissn
0006-2960issn
1520-4995journal_volume
33pub_type
杂志文章相关文献
BIOCHEMISTRY文献大全abstract::Bacterial L-asparaginases, enzymes that catalyze the hydrolysis of L-asparagine to aspartic acid, have been used for over 30 years as therapeutic agents in the treatment of acute childhood lymphoblastic leukemia. Other substrates of asparaginases include L-glutamine, D-asparagine, and succinic acid monoamide. In this ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0029595
更新日期:2001-05-15 00:00:00
abstract::Glucarate dehydratase (GlucD) from Pseudomonas putida catalyzes the dehydration of both (D)-glucarate and (L)-idarate to 3-deoxy-(L)-threo-2-hexulosarate as well as their epimerization. (D)-[6-13C]Glucarate and (L)-[6-13C]idarate have been synthesized for use in continuous assay of the reactions catalyzed by GlucD by ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi981122v
更新日期:1998-10-13 00:00:00
abstract::The amidotransferase family of enzymes utilizes the ammonia derived from the hydrolysis of glutamine for a subsequent chemical reaction catalyzed by the same enzyme. The ammonia intermediate does not dissociate into solution during the chemical transformations. A well-characterized example of the structure and mechani...
journal_title:Biochemistry
pub_type: 杂志文章,评审
doi:10.1021/bi990871p
更新日期:1999-06-22 00:00:00
abstract::The structural and functional roles of two conserved active site residues, Arg-97 and Arg-132, in chicken muscle adenylate kinase (AK) were evaluated by site-directed mutagenesis in conjunction with one- and two-dimensional proton nuclear magnetic resonance (NMR), kinetics, and guanidine hydrochloride-induced denatura...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00142a022
更新日期:1992-07-14 00:00:00
abstract::Heme uptake and utilization by pathogenic bacteria are critical for virulence and disease, since heme and heme proteins are a major source of iron within the host. Although the role of outer membrane heme receptors in this process has been extensively characterized at the genetic and biochemical level, the role of the...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi061722r
更新日期:2007-03-20 00:00:00
abstract::Thymidylate synthetase catalyzes an exchange of tritium of [5-3H]dUMP for protons of water in the absence of CH2-H4folate. The turnover number for this reaction is some 45,000-fold lower than that of dTMP formation and Km is 1.2 X 10(-5) M, similar to the dissociation constant of the enzyme-dUMP complex determined by ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00580a016
更新日期:1979-06-26 00:00:00
abstract::The effects of several divalent cations, various polybasic amines, and lysozyme on the rate of polymerization of 8S clathrin to the 300S coat structure have been evaluated by turbidimetric procedures. Ca2+ and Mn2+ strongly enhance the rate of polymerization. Only spermine among the naturally occurring polybasic amine...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00526a028
更新日期:1981-11-10 00:00:00
abstract::Mutagenesis and cross-linking measurements have identified specific contact interactions between the cytosolic and the transmembrane sequences of phospholamban (PLB) and the Ca-ATPase, and in conjunction with the high-resolution structures of PLB and the Ca-ATPase, have been used to construct models of the PLB-ATPase ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi035424v
更新日期:2004-01-20 00:00:00
abstract::The envelope glycoprotein (G protein) of vesicular stomatitis virus probably exists in the viral envelope as a trimer of identical subunits. Depending on the conditions of solubilization, G protein may dissociate into monomers. G protein solubilized with the detergent octyl glucoside was shown to exist as oligomeric f...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00462a002
更新日期:1990-03-13 00:00:00
abstract::The electrophoretic mobilities of 24 single-stranded DNA oligomers, each containing 26 nucleotide residues, have been measured in polyacrylamide gels and in free solution. The mobilities observed at 20 degrees C differed by approximately 20% in polyacrylamide gels and by approximately 10% in free solution, even though...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi701058f
更新日期:2007-09-25 00:00:00
abstract::Biochemical and immunological properties of biosynthetically radiolabeled phosphatidylcholine-(PC-) binding proteins were investigated. The PC-binding proteins were extracted from the detergent lysate of biosynthetically radiolabeled P388D1 cells by affinity chromatography on PC-Sepharose and filtered through a Sephad...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00329a014
更新日期:1985-04-09 00:00:00
abstract::Human cysteine-rich secretory protein 3 (CRISP-3; also known as SGP28) belongs to a family of closely related proteins found in mammals and reptiles. Some mammalian CRISPs are known to be involved in the process of reproduction, whereas some of the CRISPs from reptiles are neurotoxin-like substances found in lizard sa...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi048823e
更新日期:2004-10-12 00:00:00
abstract::Hemopexin is a plasma glycoprotein that has two structural domains (I and II) and binds and transports heme particularly to liver cells. Differential scanning calorimetry (DSC) studies show that hemopexin is largely stabilized by heme, which binds exclusively to domain I. The melting temperature (Tm) of heme-hemopexin...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00079a018
更新日期:1993-07-20 00:00:00
abstract::The introduction into peptide chains of alpha-aminoisobutyric acid (Aib) has proven to stabilize the helical structure in short peptides by restricting the available range of polypeptide backbone conformations. In order to evaluate the potential stabilizing effect of Aib at the protein level, we have studied the confo...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi971937o
更新日期:1998-02-10 00:00:00
abstract::The folding kinetics of a 16-residue beta-hairpin (trpzip4) and five mutants were studied by a laser-induced temperature-jump infrared method. Our results indicate that mutations which affect the strength of the hydrophobic cluster lead to a decrease in the thermal stability of the beta-hairpin, as a result of increas...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi052039s
更新日期:2006-02-28 00:00:00
abstract::The equilibrium binding and association kinetics of the Saccharomyces cerevisiae TATA Binding Protein (TBP) to the E4 and Major Late promoters of adenovirus (TATATATA and TATAAAAG, respectively), have been directly compared by quantitative DNase I titration and quench-flow "footprinting". The equilibrium binding of TB...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi981072u
更新日期:1998-11-10 00:00:00
abstract::Resonance Raman vibrational spectra of the Pr, lumi-R, and Pfr forms of phytochrome have been obtained using low-temperature trapping and room temperature flow techniques in conjunction with shifted-excitation Raman difference spectroscopy (SERDS). The Pr to lumi-R photoconversion exhibits a thermal barrier and is com...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi962175k
更新日期:1996-12-17 00:00:00
abstract::Proton and phosphorus-31 nuclear magnetic resonance (1H and 31P NMR) studies of the interaction between a tridecapeptide pheromone, the alpha-factor of Saccharomyces cerevisiae, and sonicated lipid vesicles are reported. 31P NMR studies demonstrate that there is interaction of the peptide with the phosphorus headgroup...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00436a017
更新日期:1989-05-16 00:00:00
abstract::Catalase HPII from Escherichia coli is a homotetramer of 753 residue subunits. The multimer displays a number of unusual structural features, including interwoven subunits and a covalent bond between Tyr415 and His392, that would contribute to its rigidity and stability. As the temperature of a solution of HPII in 50 ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi982863z
更新日期:1999-03-30 00:00:00
abstract::The role of the tryptophan residues in the substrate-binding and catalytic mechanism of an enzymatically active C-terminal fragment of Pseudomonas aeruginosa exotoxin A was studied by individually or jointly replacing these residues with phenylalanine. Substitution of W-466 decreased the ADP-ribosyltransferase and NAD...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi961985t
更新日期:1996-12-03 00:00:00
abstract::A cDNA coding for a P450 expressed in human lung was isolated from a lambda gt11 library constructed from human lung mRNA using a cDNA probe to rat P450 IVA1. The cDNA-deduced amino acid sequence of this P450, designated IVB1, consisted of 511 amino acids and had a calculated molecular weight of 59,558. The IVB1 amino...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00446a014
更新日期:1989-10-03 00:00:00
abstract::Ca2+-activated Z-disk-removing activity in the P0-40 crude muscle extracts described by Busch et al. (Busch, W. A., Stromer, M. H., Goll, D. E., and Suzuki, A. (1972), J. Cell Biol. 52, 367) was purified from porcine skeletal muscle extracts by using five column chromatographic procedures in succession: (1) 6% agarose...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00655a019
更新日期:1976-05-18 00:00:00
abstract::The nitrile stretching vibration is increasingly used as a sensitive infrared probe of local protein environments. However, site-specific incorporation of a nitrile moiety into proteins is difficult. Here we show that various aromatic nitriles can be easily incorporated into peptides and proteins via either thiol alky...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi101711a
更新日期:2010-12-14 00:00:00
abstract::A detailed kinetic analysis of the catalytic trimer of aspartate transcarbamoylase containing the active site substitution H134A was performed to investigate the role of His 134 in the catalytic mechanism. Replacement of histidine by alanine resulted in decreases in the affinities for the two substrates, carbamoyl pho...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00143a031
更新日期:1992-07-21 00:00:00
abstract::A protocol for complete isotopic labeling of iso-1-cytochrome c from the eukaryote Saccharomyces cerevisiae is reported. Assignments are reported for the vast majority of the 15N amide resonances in both oxidized and reduced states. 15N heteronuclear relaxation experiments were collected to study the picosecond-nanose...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi9827417
更新日期:1999-04-06 00:00:00
abstract::Filamins are a family of actin cross-linking proteins that are primarily localized in the cortical cytoplasm of all mammalian cells. Until now, three major isoforms (filamins a, b, and c) have been identified, that were shown to be differentially expressed and/or localized in different tissues. An amino-terminal doubl...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi026501+
更新日期:2003-01-21 00:00:00
abstract::We constructed and expressed chimeric receptor cDNAs with insulin receptor exon 3 (residues 191-297 of the cysteine-rich region) replaced with either the comparable region of the insulin-like growth factor I receptor (IGF-IR) or the insulin receptor related receptor (IRR). Both chimeric receptors still could bind insu...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00235a001
更新日期:1991-05-28 00:00:00
abstract::Hemophores from Serratia marcescens (HasA(sm)) and Pseudomonas aeruginosa (HasA(p)) bind hemin between two loops, which harbor the axial ligands H32 and Y75. Hemin binding to the Y75 loop triggers closing of the H32 loop and enables binding of H32. Because Yersinia pestis HasA (HasA(yp)) presents a Gln at position 32,...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi400280z
更新日期:2013-04-23 00:00:00
abstract::The dual specificity mitogen-activated protein kinase phosphatase MKP3 downregulates mitogenic signaling through dephosphorylation of extracellular signal-regulated kinase (ERK). Like other MKPs, MKP3 consists of a noncatalytic N-terminal domain and a catalytic C-terminal domain. ERK binding to the N-terminal noncatal...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi035346b
更新日期:2003-12-30 00:00:00
abstract::The binding of agonists, antagonists, and the acetylcholinesterase inhibitor, eserine, to the nicotinic acetylcholine receptor from Torpedo californica has been monitored by the fluorescence changes of two extrinsic probes that have been covalently attached to the receptor protein. Although both probes, 5-(iodoacetami...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00084a031
更新日期:1993-08-24 00:00:00