Abstract:
:Hydrogenase from Chromatium vinosum contains 1 Ni, 11-12 Fe, and ca. 9 sulfides. EPR and Mössbauer studies of the enzyme prepared in four different oxidation states show that the enzyme contains two Fe4S4 and one Fe3S4 cluster. In the oxidized (2+) state, the Mössbauer parameters of the two Fe4S4 clusters are typical for this cluster type. Upon reduction, however, these clusters do not exhibit the familiar g = 1.94 signal. The unusual nature of the reduced clusters is also borne out by the Mössbauer spectra which exhibit fairly small magnetic hyperfine interactions similar to those of centers I and II of the Desulfovibrio gigas enzyme. The Mössbauer spectra of the Fe3S4 cluster in the oxidized (1+) and reduced states are typical for this cluster type. The C. vinosum hydrogenase undergoes a reversible redox reaction at Em = +150 mV (vs NHE). Above +150 mV the EPR spectra exhibit signals (previously called signals 2 and 4) that reflect a weak interaction between Ni(III) and an Fe-containing moiety. By clamping the Ni in the diamagnetic Ni(II).CO form, we have discovered that signal 2 (X-band resonances at g = 2.01, 1.974, and 1.963) involves the Fe3S4 cluster and an as yet unidentified paramagnetic moiety. The "coupled" system exhibits magnetic hyperfine interactions quite different from those of the uncoupled [Fe3S4]1+ cluster. We have not yet been able to assign a spin to the coupled state but some of the features of the state are reminiscent of an S = 1 system. The Mössbauer data suggest, but do not prove, that an extra Fe site may be present that shuttles between low-spin Fe(III) and low-spin Fe(II) with Em = +150 mV. The Fe(III) may be located between the Ni(III) and the Fe3S4 cluster enabling it to mediate the interaction between the cluster and the Ni site. In this picture, the Fe(III) site is part of the coupled state that gives rise to signal 2. Other possibilities for signal 2 involve a ligand-based oxidation of the [Fe3S4]1+ cluster or generation of a nearby radical.
journal_name
Biochemistryjournal_title
Biochemistryauthors
Surerus KK,Chen M,van der Zwaan JW,Rusnak FM,Kolk M,Duin EC,Albracht SP,Münck Edoi
10.1021/bi00182a029subject
Has Abstractpub_date
1994-04-26 00:00:00pages
4980-93issue
16eissn
0006-2960issn
1520-4995journal_volume
33pub_type
杂志文章相关文献
BIOCHEMISTRY文献大全abstract::It has been shown that in bovine heart submitochondrial particles, antimycin and 2-heptyl-4-hydroxyquinoline N-oxide (HQNO) inhibit the oxidation of NADH, succinate, and reduced ubiquinone incompletely, the uninhibited rate being about 20-40 nmol of substrate oxidized min-1 (mg of protein)-1. By contrast, rotenone, cy...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00268a045
更新日期:1982-12-07 00:00:00
abstract::The carboxymethylation of RNase T1 at the gamma-carboxyl group of Glu58 leads to a complete loss of the enzymatic activity while it retains substrate-binding ability. Accompanying the carboxymethylation, RNase T1 undergoes a remarkable thermal stabilization of 9 degrees C in the melting temperature (Tm). In order to c...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi960493d
更新日期:1996-06-25 00:00:00
abstract::The evolutionarily conserved DRY motif at the end of the third helix of rhodopsin-like, class-A G protein-coupled receptors (GPCRs) is a major regulator of receptor stability, signaling activity, and β-arrestin-mediated internalization. Substitution of the DRY arginine with histidine in the human vasopressin receptor ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi501061h
更新日期:2015-01-27 00:00:00
abstract::Flavo-diiron proteins (FDPs) function as anaerobic nitric oxide scavengers in some microorganisms, catalyzing reduction of nitric to nitrous oxide. The FDP from Thermotoga maritima can be prepared in a deflavinated form with an intact diferric site (deflavo-FDP). Hayashi et al. [(2010) Biochemistry 49, 7040-7049] repo...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi500836z
更新日期:2014-09-09 00:00:00
abstract::Human liver alcohol dehydrogenase [alcohol:NAD+ oxidoreductase, EC 1.1.1.1 (ADH)] catalyzes the stereospecific oxidation of different 3 beta-hydroxy-5 beta-steroids with ranges of Km from 46 to 320 microM and values of kcat from 7.0 to 72 min-1, pH 8.5. Only the class I isozymes containing gamma-subunits, gamma 1 gamm...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00412a013
更新日期:1988-06-14 00:00:00
abstract::The multifunctional proline utilization A (PutA) flavoenzyme from Escherichia coli catalyzes the oxidation of proline to glutamate in two reaction steps using separate proline dehydrogenase (PRODH) and Δ(1)-pyrroline-5-carboxylate (P5C) dehydrogenase domains. Here, the kinetic mechanism of PRODH in PutA is studied by ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi201603f
更新日期:2012-01-10 00:00:00
abstract::Neuropeptide Y (NPY) and the pancreatic polypeptide (PP) are members of the neuropeptide Y family of hormones. They bind to the Y receptors with very different affinities: Whereas PP is highly selective for the Y(4) receptor, NPY displays highest affinites for Y(1), Y(2), and Y(5) receptor subtypes. Introducing the NP...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0501232
更新日期:2005-06-28 00:00:00
abstract::Two novel heme-containing peroxidases, one able to incorporate halogens into aromatic substrates and the other able to remove them, have recently been isolated from marine sources and initially characterized by Chen et al. [(1991) J. Biol. Chem. 266, 23909-23915; (1996) J. Biol. Chem. 271, 4609-4612]. The haloperoxida...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi9621371
更新日期:1997-02-25 00:00:00
abstract::The heme propionate groups of both myoglobin (Mb) and cytochrome b5 form hydrogen bonds with nearby surface amino acids residues that are believed to stabilize the heme-protein complex. To evaluate the magnitude of this stabilization, the kinetics of heme dissociation from variants of horse heart Mb and cytochrome b5 ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi961385u
更新日期:1997-02-04 00:00:00
abstract::The effect of tropomyosin alone on the binding of myosin subfragment 1 (S-1) to actin was compared to that of troponin-tropomyosin, with and without Ca2+. Over a range of ionic strength and with different ligands (adenyl-5'-yl imidodiphosphate, pyrophosphate, and adenosine 5'-diphosphate), tropomyosin confers slight c...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00280a027
更新日期:1983-05-24 00:00:00
abstract::A common motif in protein structures is the assembly of alpha-helices. Natural alpha-helical assemblies, such as helical bundles and coiled coils, consist of multiple right-handed alpha-helices. Here we design a protein complex containing both left-handed and right-handed helices, with peptides of D- and L-amino acids...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi010725v
更新日期:2001-07-31 00:00:00
abstract::RecG is a DNA helicase involved in the repair of damage at a replication fork and catalyzes the reversal of the fork to a point beyond the damage in the template strand. It unwinds duplex DNA in reactions that are coupled to ATP hydrolysis. The kinetic mechanism of duplex DNA unwinding by RecG was analyzed using a qua...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0512851
更新日期:2005-12-27 00:00:00
abstract::The "stalk" of the prokaryotic 50S ribosomal subunit is comprised of four copies of the protein L7/L12. In Escherichia coli, L7/L12 is a dimeric protein at micromolar concentrations, which is able to undergo rapid subunit exchange. A recent structural study indicated a tetrameric arrangement of the L12 proteins isolat...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi048015n
更新日期:2005-03-08 00:00:00
abstract::Administration of pregnenolone-16 alpha-carbonitrile (PCN) to adult female rats caused a 2-fold increase in total liver microsomal cytochrome P-450 along with 5-7-fold increases in four in vitro monooxygenase activities considered diagnostic for the major PCN-inducible cytochrome P-450 isozyme. However, upon administr...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00387a022
更新日期:1987-06-30 00:00:00
abstract::Purple membranes of Halobacterium halobium were studied by differential scanning calorimetry. No transition was detected at temperatures below 70 degrees C. A small endothermic transition was seen at about 80 degrees C and a larger one at 100 degrees C. The larger transition is the irreversible denaturation of bacteri...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00598a026
更新日期:1978-03-07 00:00:00
abstract::The flavoenzyme tryptophan 2-monooxygenase catalyzes the oxidation of tryptophan to indoleacetamide, carbon dioxide, and water. The enzyme is a homologue of l-amino acid oxidase. In the structure of l-amino acid oxidase complexed with aminobenzoate, Tyr372 hydrogen bonds with the carboxylate of the inhibitor in the ac...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi035300i
更新日期:2003-12-02 00:00:00
abstract::Complete 1H NMR sequential assignments have been made for copper(I)- and silver (I)-substituted metallothionein (MT) from Saccharomyces cerevisiae using standard 2D 1H NMR methods. The fingerprint region of the COSY spectrum of both metalloproteins shows a doubling of a few backbone proton resonances from residue K41 ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00077a032
更新日期:1993-07-06 00:00:00
abstract::Structural features of a 19-nucleotide RNA hairpin loop (5'-GGCGUACGUUUCGUACGCC-3'), a loop motif which occurs in eukaryotic 18S rRNA, have been derived using multidimensional heteronuclear NMR spectroscopy in combination with local conformational analysis and torsion angle distance geometry followed by restrained ene...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi971207g
更新日期:1997-11-18 00:00:00
abstract::Pyruvate dehydrogenase kinase 2 (PDK2) activity is enhanced by the dihydrolipoyl acetyltransferase core (E2 60mer) that binds PDK2 and a large number of its pyruvate dehydrogenase (E1) substrate. With E2-activated PDK2, K(+) at approximately 90 mM and Cl(-) at approximately 60 mM decreased the K(m) of PDK2 for ATP and...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi049488x
更新日期:2004-10-26 00:00:00
abstract::Protein translocation in Escherichia coli is mediated by the SecA ATPase bound to the SecYEG membrane protein complex. SecA translocation ATPase activity as well as protein translocation is dependent on the presence of negatively charged lipids. By using a phospholipid with an acyl chain linked photoactivatable group,...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi9809021
更新日期:1998-09-01 00:00:00
abstract::X-ray absorption spectroscopy at the Zn K-edge indicates that the active site of the marine diatom Thalassiosira weissflogii carbonic anhydrase is strikingly similar to that of mammalian alpha-carbonic anhydrase enzymes. The zinc has three histidine ligands and a single water at 1.98 A. This is quite different from th...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi001416s
更新日期:2000-10-10 00:00:00
abstract::The virally encoded integrase protein carries out retroviral integration, which requires specific interactions with the two ends of the viral DNA, and also with host DNA that is the target of integration. We attached a photo-cross-linking agent to specific viral and target DNA sites to identify regions of the integras...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi972949c
更新日期:1998-05-12 00:00:00
abstract::The aromatic hydroxylation of six pairs of selectively deuterated monosubstituted benzenes was investigated with rat liver microsomes of various induction states. The substrates studied included 3,5-D2C6H3X (1a-6a) and 2,4,6-D3C6H2X (1b-6b), where X = Br, CN, NO2, OCH3, CH3, or Ph, respectively. The deuterium content ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00308a031
更新日期:1984-06-19 00:00:00
abstract::The photoaddition of 4'-(hydroxymethyl)-4,5',8-trimethylpsoralen (HMT) to different conformational states of RNA was studied. Poly(U), poly(A,U) (random copolymer), poly(A-U) (alternating copolymer), poly(A) . poly(U) (double stranded), and poly(U) . poly(A) . poly(U) (triple stranded) were reacted with HMT at differe...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00535a040
更新日期:1982-03-16 00:00:00
abstract::Two successive steps in de novo purine biosynthesis are catalyzed by the enzymes 5-aminoimidazole ribonucleotide (AIR) carboxylase and 4-[(N-succinylamino)carbonyl]-5-aminoimidazole ribonucleotide (SAICAR) synthetase. Amino acid sequence alignments of the proteins from various sources suggested that several unusual di...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00205a030
更新日期:1994-10-04 00:00:00
abstract::The role of the 2'-hydroxyl group in RNA--protein interaction has been investigated using MS2 coat protein and its hairpin RNA operator as a model system. Derivatives of the MS2 translational operator were prepared where individual riboses were replaced by deoxyribose and their binding affinities to MS2 coat protein w...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00038a033
更新日期:1995-09-26 00:00:00
abstract::FKBP12, a small human enzyme, aids protein folding by catalyzing cis-trans isomerization of peptidyl-prolyl bonds, and is involved in cell signaling pathways, calcium regulation, and the immune response. The underlying molecular mechanisms are not fully understood, but it is well-known that aromatic residues in the ac...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.6b01157
更新日期:2017-01-10 00:00:00
abstract::A soluble extract prepared from cells of an Escherichia coli strain carrying the antibiotic resistance plasmid R6K is capable of carrying out the complete process of R6K DNA replication. DNA synthesis in vitro is dependent on the four deoxyribo- and ribonucleotide triphosphates and is sensitive to rifampin and strepto...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00606a017
更新日期:1978-06-27 00:00:00
abstract::Over 20 years ago, it was reported that liver cytosol contains at least two distinct proteins that transfer phosphatidylinositol in vitro, phosphatidylinositol transfer protein (PITP) and a pH 5.1 supernatant fraction containing sterol carrier protein-2 (SCP-2). In contrast to PITP, there has been minimal progress on ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi026904+
更新日期:2003-03-25 00:00:00
abstract::The proteasome inhibitors, lactacystin and N-acetyl-leucyl-leucyl-norlucinal, caused a rapid and near-complete loss of approximately 22-23-kDa ubiquitinated nucleoproteins, which we have identified as monoubiquitinated nucleosomal histones H2A and H2B by immunological and two-dimensional electrophoretic techniques. In...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi970998j
更新日期:1997-11-25 00:00:00