Abstract:
:The effect of DnaB helicase on the initiation specificity of primase was studied biochemically using a series of single-stranded DNA templates in which each nucleotide of the trinucleotide d(CTG) initiation sequence was systematically varied. DnaB helicase accelerated the rate of primer syntheisis, prevented "overlong" primers from forming and decreased the initiation specificity of primase. In the presence of DnaB helicase, all trinucleotides could serve as the primer initiation site although there was a distinct preference for d(CAG). These data may explain the high chromosomal prevalence of octanucleotides containing CTG on the leading strand and its complement CAG on the lagging strand. The specificity of DnaB helicase places it on the lagging strand template where it stimulates the initiation of Okazaki fragment synthesis. In the absence of DnaB helicase, primase preferentially primed the d(CTG) template. In the presence of DnaB helicase, the initiation preference was not only altered but also the preferred initiating nucleotide was found to be GTP rather than ATP, for both the d(CTG) and the d(CAG) templates. This suggested that the specificity of primase for the d(CTG) initiation trinucleotide was predominantly unaffected in the absence of DnaB helicase on short ssDNA templates, whereas in conjunction with DnaB helicase, the specificity was altered and this alteration has significant implications in the replication of Escherichia coli chromosome in vivo.
journal_name
Biochemistryjournal_title
Biochemistryauthors
Bhattacharyya S,Griep MAdoi
10.1021/bi991555dsubject
Has Abstractpub_date
2000-02-01 00:00:00pages
745-52issue
4eissn
0006-2960issn
1520-4995pii
bi991555djournal_volume
39pub_type
杂志文章相关文献
BIOCHEMISTRY文献大全abstract::The bidirectional transformation of a protein between its native water-soluble and integral transmembrane conformations is demonstrated for FraC, a hemolytic protein of the family of pore-forming toxins. In the presence of biological membranes, the water-soluble conformation of FraC undergoes a remarkable structural r...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.5b01112
更新日期:2015-11-24 00:00:00
abstract::Multiple intracellular receptors of the FK506 binding protein (FKBP) family of peptidylprolyl cis/trans-isomerases are potential targets for the immunosuppressive drug FK506. Inhibition of the protein phosphatase calcineurin (CaN), which has been implicated in the FK506-mediated blockade of T cell proliferation, was s...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi061616p
更新日期:2006-12-26 00:00:00
abstract::The protective effect of cyclic stable nitroxide free radicals, having SOD-like activity, against oxidative damage was studied by using Escherichia coli xthA DNA repair-deficient mutant hypersensitive to H2O2. Oxidative damage induced by H2O2 was assayed by monitoring cell survival. The metal chelator 1,10-phenanthrol...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00216a033
更新日期:1991-01-15 00:00:00
abstract::Factor XIII is the terminal enzyme of the clotting cascade. A cDNA sequence encoding human placental factor XIII was expressed in Saccharomyces cerevisiae with the yeast ADH2-4c promoter. Expression levels were a strong function of the noncoding flanking DNA content of the construction. When the terminal 3'-flanking n...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00459a028
更新日期:1990-02-20 00:00:00
abstract::Previous crystallographic studies in this laboratory demonstrated that immunoglobulin light chains with the same amino acid sequence can have at least two and probably three or more conformations, depending on whether the second member of an interacting pair is a light or heavy chain. If a heavy chain is not available...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00594a022
更新日期:1978-01-10 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 conformational analysis of non-native states of proteins remains one of the most difficult problems in structural biology, because such states are represented by a superimposition of several states that are rapidly interconverting. Hence, model building of the conformational ensemble remains challenging, although ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi300222f
更新日期:2012-04-24 00:00:00
abstract::High-molecular mass thioredoxin reductases (TRs) are pyridine nucleotide disulfide oxidoreductases that catalyze the reduction of the disulfide bond of thioredoxin (Trx). Trx is responsible for reducing multiple protein disulfide targets in the cell. TRs utilize reduced β-nicotinamide adenine dinucleotide phosphate to...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi400931k
更新日期:2014-01-28 00:00:00
abstract::NAD(P)H:quinone oxidoreductase 1 (NQO1) is currently an emerging target in pancreatic cancer. In this report, we describe a series of indolequinones, based on 5-methoxy-1,2-dimethyl-3-[(4-nitrophenoxy)methyl]indole-4,7-dione (ES936), and evaluate NQO1 inhibition and growth inhibitory activity in the human pancreatic M...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi700008y
更新日期:2007-05-22 00:00:00
abstract::It is now appreciated that the relationships of proteins, particularly enzymes, within a protein superfamily can be understood not only in terms of their sequence similarities and three-dimensional structures but also by chemical threads that relate their functional attributes. The mechanistic ties among superfamily m...
journal_title:Biochemistry
pub_type: 杂志文章,评审
doi:10.1021/bi001814v
更新日期:2000-11-14 00:00:00
abstract::We describe a real-time assay for the interaction of the G-protein of retinal rods, transducin (Gt), with its effector, cGMP phosphodiesterase (PDE). The purified proteins were recombined with isolated rod disk membranes. Reactions were triggered by flash photolysis of the receptor rhodopsin, and monitored by changes ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00083a024
更新日期:1993-08-17 00:00:00
abstract::The alpha-helix [Pauling, L., Corey, R. B., & Branson, H. R. (1951) Proc. Natl. Acad. Sci. U.S.A. 37, 205-211] is a common motif in both proteins and peptides. Despite intense investigation, predictive understanding of helices is still lacking. A recent hypothesis [Presta, L. G., & Rose, G. D. (1988) Science 240, 1632...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00081a001
更新日期:1993-08-03 00:00:00
abstract::A ribonuclease was isolated from serum-free supernatants of the human colon adenocarcinoma cell line HT-29. It was purified by cation-exchange and C18 reversed-phase high-performance liquid chromatography. The protein is basic, has a molecular weight of approximately 16,000, and has an amino acid composition that is s...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00371a002
更新日期:1986-11-18 00:00:00
abstract::The acetylenic analogue of adenosine 9-(5',6'-dideoxy-beta-D-ribo-hex-5'-ynofuranosyl)adenine has been synthesized, and its behavior as an inhibitor of bovine S-adenosylhomocysteine hydrolase has been examined. Incubation of the enzyme with excess inhibitor caused a time-dependent, irreversible inactivation of the enz...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00105a025
更新日期:1991-10-15 00:00:00
abstract::Transcarboxylase (TC) is a multisubunit enzyme that catalyzes the transfer of a carboxylate group from methylmalonyl-CoA (MMCoA) to pyruvate. The CO2- group is shuttled between the MMCoA and pyruvate binding sites by a biotin cofactor, covalently linked to the 1.3S subunit. Fully carboxylated 1.3S can be prepared in v...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0116442
更新日期:2002-02-19 00:00:00
abstract::The contribution of ligand dynamics to CYP allosterism has not been considered in detail. On the basis of a previous study, we hypothesized that CYP2A6 and CYP2E1 accommodate multiple xylene ligands. As a result, the intramolecular ( k H/ k D) obs values observed for some xylene isomers are expected to be dependent on...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi702020y
更新日期:2008-03-04 00:00:00
abstract::The gene encoding enzyme I of the phosphoenolpyruvate:sugar phosphotransferase system from an Escherichia coli enzyme I mutant was cloned and sequenced. The mutation was shown to be a guanine to adenine transition resulting in an altered protein in which glycine-338 was replaced by aspartic acid. The enzyme I structur...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi952052k
更新日期:1996-01-09 00:00:00
abstract::The conformational change of the model peptide Ac-K-G-R-G-D-G-amide induced by a phospholipidic interface was investigated by proton nuclear magnetic resonance (1H NMR). In aqueous solution, the free peptide is highly flexible and disordered, even in the presence of deuterated dodecyl-phosphocholine (DPC-d38) micelles...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00124a018
更新日期:1992-03-10 00:00:00
abstract::An oligodeoxynucleotide containing four thymines and covalently attached to an acridine derivative through its 3'-phosphate [(Tp)4(CH2)5Acr] was synthesized. Its conformation in solution was investigated by proton magnetic resonance. Both intramolecular interactions between the acridine dye and thymines and intermolec...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00331a019
更新日期:1985-05-07 00:00:00
abstract::We have used a new fluorescent ATP analogue, 3'-(7-diethylaminocoumarin-3-carbonylamino)-3'-deoxyadenosine-5'-triphosphate (deac-aminoATP), to study the ATP hydrolysis mechanism of the single headed myosinV-S1. Our study demonstrates that deac-aminoATP is an excellent substrate for these studies. Although the deac-ami...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi060712n
更新日期:2006-10-31 00:00:00
abstract::In the native calcium-binding protein calbindin D9k (M(r) 8.700; 75aa; 2 EF-hands), the backbone carbonyl oxygen of Glu60 coordinates the Ca2+ ion in the C-terminal site (site II). The carboxylate group of the same residue forms a hydrogen bond to a water molecule that constitutes a Ca2+ ligand in the N-terminal site ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00207a015
更新日期:1994-10-18 00:00:00
abstract::Tropomyosin is postulated to confer stability to actin filaments in nonmuscle cells. We have found that a nonmuscle tropomyosin isolated from the intestinal epithelium can directly stabilize actin filaments by slowing depolymerization from the pointed, or slow-growing, filament end. Kinetics of elongation and depolyme...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00447a035
更新日期:1989-10-17 00:00:00
abstract::The molecular structure of ammonium deoxycytidylyl-(3'-5')-deoxyguanosine, crystallized from aqueous acetone near pH 4, was determined for X-ray diffraction data. The crystals were tetragonal, space group P43212 with a = b = 11.078 (1) A and c = 45.826 (4) A. The structure was solved by tangent expansion of phases bas...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00277a014
更新日期:1983-04-12 00:00:00
abstract::We report the use of electrospray ionization (ESI) mass spectrometry (MS) in conjunction with online rapid mixing to monitor the kinetics of acid-induced ferrihemoglobin denaturation. Under equilibrium conditions, the hemoglobin mass spectrum is dominated by the intact heterotetramer. Dimeric and monomeric species are...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi048501a
更新日期:2004-11-23 00:00:00
abstract::The interactions of a series of spin-labeled fatty acids, in which the nitroxide ring is incorporated in different ways as an integral part of the hydrocarbon chain, with the (Na+,K+)-ATPase in membranes from Squalus acanthias, have been studied by electron spin resonance spectroscopy. The fatty acids are 2,4-, 2,5-, ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00411a004
更新日期:1988-05-31 00:00:00
abstract::L-Aspartate oxidase (Laspo) catalyzes the conversion of L-Asp to iminoaspartate, the first step in the de novo biosynthesis of NAD(+). This bacterial pathway represents a potential drug target since it is absent in mammals. The Laspo R386L mutant was crystallized in the FAD-bound catalytically competent form and its t...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi015939r
更新日期:2002-03-05 00:00:00
abstract::We have initiated a broad-based program aimed at understanding the molecular basis of fluorine specificity in enzymatic systems, and in this context, we report crystallographic and biochemical studies on a fluoroacetyl-coenzyme A (CoA) specific thioesterase (FlK) from Streptomyces cattleya. Our data establish that FlK...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi101102u
更新日期:2010-11-02 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::Phenylalanine 87 of Bacillus megaterium cytochrome P450 BM3, a residue close to the heme in the substrate binding pocket, has been replaced by alanine by site-directed mutagenesis. The substitution had no effect on the rate of hydroxylation of laurate and increased the affinity for laurate of both the intact enzyme an...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi962826c
更新日期:1997-02-18 00:00:00
abstract::The reaction of Pseudomonas fluorescens kynureninase with L-kynurenine and L-alanine has been examined using rapid-scanning stopped-flow spectrophotometry. Mixing kynureninase with 0.5 mM L-kynurenine results in formation of a quinonoid intermediate, with lambdamax = 494 nm, within the dead time (ca. 2 ms) of the stop...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi980066v
更新日期:1998-06-16 00:00:00