Abstract:
:Heme oxygenase-1 (HO-1) is an enzyme that catalyzes the oxidative degradation of heme. Since free heme is toxic to cells, rapid degradation of heme is important for maintaining cellular health. There have been useful mechanistic studies of the HO reaction based on crystal structures; however, how HO-1 recognizes heme is not completely understood because the crystal structure of heme-free rat HO-1 lacks electron densities for A-helix that ligates heme. In this study, we characterized conformational dynamics of HO-1 using NMR to elucidate the mechanism by which HO-1 recognizes heme. NMR relaxation experiments showed that the heme-binding site in heme-free HO-1 fluctuates in concert with a surface-exposed loop and transiently forms a partially unfolded structure. Because the fluctuating loop is located over 17 Å distal from the heme-binding site and its conformation is nearly identical among different crystal structures including catalytic intermediate states, the function of the loop has been unexamined. In the course of elucidating its function, we found interesting mutations in this loop that altered activity but caused little change to the conformation. The Phe79Ala mutation in the loop changed the conformational dynamics of the heme-binding site. Furthermore, the heme binding kinetics of the mutant was slower than that of the wild type. Hence, we concluded that the distal loop is involved in the regulation of the conformational change for heme binding through the conformational fluctuations. Similar to other enzymes, HO-1 effectively promotes its function using the identified distal sites, which might be potential targets for protein engineering.
journal_name
Biochemistryjournal_title
Biochemistryauthors
Harada E,Sugishima M,Harada J,Fukuyama K,Sugase Kdoi
10.1021/bi5009694subject
Has Abstractpub_date
2015-01-20 00:00:00pages
340-8issue
2eissn
0006-2960issn
1520-4995journal_volume
54pub_type
杂志文章相关文献
BIOCHEMISTRY文献大全abstract::Conformational changes in the prion protein cause transmissible spongiform encephalopathies, also referred to as prion diseases. In its native state, the prion protein is innocuous (PrPC), but it can misfold into a neurotoxic and infectious isoform (PrPSc). The full-length cellular form of the prion protein consists o...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0619066
更新日期:2007-03-20 00:00:00
abstract::Type VI collagen, prepared from guanidine extracts of human amnion, contains very little monomeric material, the major forms being dimers and tetramers. In order to study the orientation of the molecules in these aggregates, they were digested with pepsin followed by bacterial collagenase. Two fragments were isolated,...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00435a020
更新日期:1989-05-02 00:00:00
abstract::Neutral oligosaccharides, which accounted for 74% of the total N-linked sugar chains released by hydrazinolysis of rat small intestinal aminopeptidase N, were investigated on a structural basis. They are mainly composed of complex-type sugar chains with tri- and tetraantennary structures, and small amounts of high man...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00101a028
更新日期:1991-09-17 00:00:00
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::In this work, we obtain the data needed to predict chemical interactions of polyethylene glycols (PEGs) and glycerol with proteins and related organic compounds and thereby interpret or predict chemical effects of PEGs on protein processes. To accomplish this, we determine interactions of glycerol and tetraEG with >30...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.5b00246
更新日期:2015-06-09 00:00:00
abstract::Neutral solutes were used to investigate the effects of osmotic stress both on the ability of rhodopsin to undergo its activating conformation change and on acyl chain packing in the rod outer segment (ROS) disk membrane. The equilibrium concentration of metarhodopsin II (MII), the conformation of photoactivated rhodo...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi990634m
更新日期:1999-06-15 00:00:00
abstract::Four polypeptide chains composing acetylcholine receptors from the electric organ of Torpedo californica were purified by preparative electrophoresis in sodium dodecyl sulfate. Their apparent mole ratio alpha/beta/gamma/delta is 2:1:1:1. These chains are not readily distinguished by amino acid or carbohydrate composit...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00588a003
更新日期:1979-10-16 00:00:00
abstract::The reactivity of the mitochondrial (pI = 5) isoenzyme of horse liver aldehyde dehydrogenase was determined by studying the effects of pH on steady-state velocity, burst magnitude, and molecular weight of the enzyme in the absence and presence of Mg2+ ions. The Mg2+ ion activation of the steady-state velocity at pH 7....
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00524a049
更新日期:1981-10-13 00:00:00
abstract::The EcoRV restriction endonuclease cleaves DNA at its recognition sequence more readily with Mg2+ as the cofactor than with Mn2+ but, at noncognate sequences that differ from the EcoRV site by one base pair, Mn2+ gives higher rates than Mg2+. A mutant of EcoRV, in which an isoleucine near the active site was replaced ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi9523926
更新日期:1996-02-13 00:00:00
abstract::Penicillin-binding protein 5 (PBP 5) from Escherichia coli is a well-characterized d-alanine carboxypeptidase that serves as a prototypical enzyme to elucidate the structure, function, and catalytic mechanism of PBPs. A comprehensive understanding of the catalytic mechanism underlying d-alanine carboxypeptidation and ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0473004
更新日期:2005-06-14 00:00:00
abstract::The chemoreceptors of Escherichia coli are homodimeric membrane proteins that cluster in patches near the cell poles. They convert environmental stimuli into intracellular signals that control flagellar rotation. The functional domains of a receptor are physically separated by the cell membrane. Chemoeffectors bind to...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi048969d
更新日期:2005-02-01 00:00:00
abstract::Both activities of the aspartokinase--homoserine I (AK-HSD) of Escherichia coli are inhibited by threonine. Careful threonine binding studies have now been done which have allowed us to distinguish the various effects of threonine on the enzyme. The ultrafiltration technique of H. Paulus ((1969) Anal. Biochem. 32, 101...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00610a014
更新日期:1978-08-22 00:00:00
abstract::We show here that expression of chromogranins in non-neuroendocrine NIH3T3 cells significantly increased the amount of IP(3)-mediated intracellular Ca(2+) mobilization in these cells, whereas suppression of them in neuroendocrine PC12 cells decreased the amount of mobilized Ca(2+). We have therefore investigated the r...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi048070w
更新日期:2005-04-26 00:00:00
abstract::Regulation of Saccharomyces cerevisiae membrane-associated phosphatidate phosphatase (3-sn-phosphatidate phosphohydrolase, EC 3.1.3.4) activity by phospholipids was examined using purified enzyme and Triton X-100/phospholipid-mixed micelles. Anionic phospholipids activated phosphatidate phosphatase activity whereas zw...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi952808f
更新日期:1996-03-26 00:00:00
abstract::The role of the peripheral reaction center chlorophyll a molecule associated with His117 of the D2 polypeptide in photosystem II was investigated in Synechocystis sp. PCC 6803 using a combination of steady state, pump-probe, and picosecond time-resolved fluorescence spectroscopy. Data were obtained from intact cells a...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi000476v
更新日期:2000-11-21 00:00:00
abstract::We have examined the competitive binding of oxygen and carbon monoxide to the multisubunit hemocyanin of the tarantula Eurypelma californicum. Employment of high-precision thin-layer methods has enabled detailed characterization of the pure oxygen and pure carbon monoxide binding curves, as well as binding curves perf...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00418a036
更新日期:1988-09-06 00:00:00
abstract::The specificity of trypsin for Arg- and Lys-containing substrates depends upon the presence of Asp189 at the base of the primary binding pocket. The crystal structure of anionic rat trypsin D189S complexed with BPTI reveals that removal of the aspartate side chain permits the binding of a well-ordered acetate ion in a...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00177a016
更新日期:1994-03-22 00:00:00
abstract::A conformational transition is described for the polypeptide, gramicidin A, in which a dimer that forms a left-handed intertwined antiparallel helix is converted to a single-stranded amino terminus to amino terminus right-handed helix. The starting structure is determined here by solution NMR methods while reference i...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00152a019
更新日期:1992-09-22 00:00:00
abstract::The five-membered nitrogen plus heteroatom rings known as azolines or in their oxidized form as azoles are very common in natural products and drugs. The oxidation of thiazoline to thiazole in the cyanobactin class of natural products is one of the several important transformations that are known to alter the biologic...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.8b00835
更新日期:2018-10-16 00:00:00
abstract::Steady-state kinetic studies for the reaction of the flavocytochrome p-cresol methylhydroxylase with the reducing substrates (S) p-cresol, 4-ethylphenol, and their corresponding alpha-deuteriated analogues are presented. The results from these experiments and those from studies involving various reoxidizing substrates...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00387a055
更新日期:1987-06-30 00:00:00
abstract::Multidrug resistance protein (MRP) and P-glycoprotein (Pgp) are both members of the superfamily of ATP binding cassette plasma membrane drug transport proteins, which may be partly responsible for multidrug resistance of tumor cells. Although MRP has been identified as an organic anion transporter and Pgp as a transpo...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi9718043
更新日期:1998-02-24 00:00:00
abstract::In mammals, citric acid cycle intermediates play a key role in regulating various metabolic processes, such as fatty acid synthesis and glycolysis. Members of the sodium-dependent SLC13 transporter family mediate the transport of di- and tricarboxylates into cells. SLC13 family members have been implicated in lifespan...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.5b00388
更新日期:2015-08-11 00:00:00
abstract::The calcitonin gene-related peptide (CGRP) receptor is a heterodimer of two membrane proteins: calcitonin receptor-like receptor (CLR) and receptor activity-modifying protein 1 (RAMP1). CLR is a class B G-protein-coupled receptor (GPCR), possessing a characteristic large amino-terminal extracellular domain (ECD) impor...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi901848m
更新日期:2010-03-09 00:00:00
abstract::Much interest is currently focused on understanding the detailed contribution that particular amino acid residues make in protein structure and function. Although the use of site-directed mutagenesis has greatly contributed to this goal, the approach is limited to the standard repertoire of twenty amino acids. Fluorin...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi9617973
更新日期:1997-03-18 00:00:00
abstract::The left-handed polyproline II (P(II)) helix is a structure that has been given a great deal of attention lately because of its role in a wide variety of physiologically important processes and potential significance in protein unfolded states. Recent work by several authors has shown that residues besides proline can...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi049922v
更新日期:2004-05-18 00:00:00
abstract::The gene product 61 primase protein from bacteriophage T4 was expressed as an intein fusion and purified to homogeneity. The primase binds one zinc ion, which is coordinated by four cysteine residues to form a zinc ribbon motif. Factors that influence the rate of priming were investigated, and a physiologically releva...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0108554
更新日期:2001-12-18 00:00:00
abstract::In this paper, we report kinetic studies for the chymotryptic activity of the 20S proteasome. Major observations include the following: (1) Reaction progress curves that are recorded at concentrations of Suc-Leu-Leu-Val-Tyr-AMC greater than about 40 microM are biphasic and characterized by initial velocities that deca...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi952262x
更新日期:1996-04-02 00:00:00
abstract::Antimicrobial peptides (AMPs) are important components of the host innate immune system. Papiliocin is a 37-residue AMP purified from larvae of the swallowtail butterfly Papilio xuthus. Magainin 2 is a 23-residue AMP purified from the skin of the African clawed frog Xenopus laevis. We designed an 18-residue hybrid pep...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.5b00392
更新日期:2015-06-30 00:00:00
abstract::At any instant, the human erythrocyte sugar transporter presents at least one sugar export site but multiple sugar import sites. The present study asks whether the transporter also presents more than one sugar exit site. We approached this question by analysis of binding of [3H]cytochalasin B (an export conformer liga...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi015586w
更新日期:2001-12-25 00:00:00
abstract::Comparative primary structural analyses have begun to elucidate polymorphic residues and segments of the class I antigens of the major histocompatibility complex, at least some of which presumably contribute to determinants important in immune recognition events. HLA-A2 structural variants have been described which ar...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00267a042
更新日期:1982-11-23 00:00:00