Abstract：
:DnaB helicase is responsible for unwinding duplex DNA during chromosomal DNA replication and is an essential component of the DNA replication apparatus in Escherichia coli. We have analyzed the mechanism of binding of single-stranded DNA (ssDNA) by the DnaB x DnaC complex and DnaB helicase. Binding of ssDNA to DnaB helicase was significantly modulated by nucleotide cofactors, and the modulation was distinctly different for its complex with DnaC. DnaB helicase bound ssDNA with a high affinity [Kd = (5.09 +/- 0.32) x 10(-8) M] only in the presence of ATPgammaS, a nonhydrolyzable analogue of ATP, but not other nucleotides. The binding was sensitive to ionic strength but not to changes in temperature in the range of 30-37 degrees C. On the other hand, ssDNA binding in the presence of ADP was weaker than that observed with ATPgammaS, and the binding was insensitive to ionic strength. DnaC protein hexamerizes to form a 1:1 complex with the DnaB hexamer and loads it onto the ssDNA by forming a DnaB6 x DnaC6 dodecameric complex. Our results demonstrate that the DnaB6 x DnaC6 complex bound ssDNA with a high affinity [Kd = (6.26 +/- 0.65) x 10(-8) M] in the presence of ATP, unlike the DnaB hexamer. In the presence of ATPgammaS or ADP, binding of ssDNA by the DnaB6 x DnaC6 complex was a lower-affinity process. In summary, our results suggest that in the presence of ATP in vivo, the DnaB6 x DnaC6 complex should be more efficient in binding DNA as well as in loading DnaB onto the ssDNA than DnaB helicase itself.
journal_name
Biochemistryjournal_title
Biochemistryauthors
Biswas SB,Biswas-Fiss EEdoi
10.1021/bi060118dsubject
Has Abstractpub_date
2006-09-26 00:00:00pages
11505-13issue
38eissn
0006-2960issn
1520-4995journal_volume
45pub_type
杂志文章相关文献
BIOCHEMISTRY文献大全abstract：:Tularemia is a severe infectious disease in humans caused by the Gram-negative bacterium Francisella tularensis (Ft). Because of its low infectious dose, high mortality rate, and the threat of its large-scale dissemination in weaponized form, development of vaccines and immunotherapeutics against Ft is essential. Ft l...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi201450v
更新日期：2011-12-20 00:00:00
abstract：:The reduction of substrates catalyzed by nitrogenase utilizes an electron transfer (ET) chain comprised of three metalloclusters distributed between the two component proteins, designated as the Fe protein and the MoFe protein. The flow of electrons through these three metalloclusters involves ET from the [4Fe-4S] clu...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi201003a
更新日期：2011-11-01 00:00:00
abstract：:Temperature-jump experiments were performed with di-, tetra-, and hexasaccharides derived from type III pneumococcal polysaccharide using a homogeneous corresponding antibody IgG 45-394. A decrease in stability of the oligosaccharide-antibody complexes with decreasing chain length was observed and entirely reflected i...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00637a023
更新日期：1977-09-06 00:00:00
abstract：:Transporters from the SLC13 family couple the transport of two to four Na+ ions with a di- or tricarboxylate, such as succinate or citrate. We have previously modeled mammalian members of the SLC13 family, including the Na+/dicarboxylate cotransporter NaDC1 (SLC13A2), based on a structure of the bacterial homologue Vc...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/acs.biochem.7b00503
更新日期：2017-08-22 00:00:00
abstract：:The peptide cyclo(hex-Amb(1)-Cys(2))-Thr(3)-Val(4)-Thr(5)-Nph(6)-NH2 was previously shown to be a slow, tight-binding inhibitor (Ki = 37 nM) of the yeast oligosaccharyl transferase (OT) [Hendrickson et al. (1996) J. Am. Chem. Soc. 118, 7636-7637]. This enzyme catalyzes the transfer of a carbohydrate moiety to an aspar...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi971465d
更新日期：1997-10-14 00:00:00
abstract：:Sin3 forms the scaffold for a multiprotein corepressor complex that silences transcription via the action of histone deacetylases. Sin3 is recruited to the DNA by several DNA binding repressors, such as the helix-loop-helix proteins of the Mad family. Here, we elaborate on the Mad-Sin3 interaction based on a binding s...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi0355645
更新日期：2004-01-13 00:00:00
abstract：:The enzyme RhlI catalyzes the formation of N-butyrylhomoserine lactone from S-adenosylmethionine and N-butyrylacyl carrier protein. N-Butyrylhomoserine lactone serves as a quorum-sensing signal molecule in Pseudomonas aeruginosa, and is implicated in the regulation of many processes involved in bacterial virulence and...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi048005m
更新日期：2005-03-01 00:00:00
abstract：:Circular dichroism spectra of the partially folded trapped intermediates were measured in order to aid in the elucidation of the conformational forces which determine a nonrandom, nonsequential pathway of disulfide bond formation upon refolding of bovine pancreatic trypsin inhibitor. Whatever conformation was responsi...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00279a020
更新日期：1983-05-10 00:00:00
abstract：:Translation of mRNAs by the ribosome is stereospecific, with only l-amino acids being incorporated into the nascent polypeptide chain. This stereospecificity results from the exclusion of d-amino acids at three steps during protein synthesis: (1) the aminoacylation of tRNA by aminoacyl-tRNA synthetases, (2) binding of...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/acs.biochem.5b01167
更新日期：2016-03-15 00:00:00
abstract：:1-Deoxy-D-fructose was synthesized in 27% yield from D-glucosamine in a three-step procedure involving Raney nickel desulfurization and oxidative deamination with 3,5-di-tert-butyl- 1,2-benzoquinone applied to appropriate intermediates. 1-Deoxyfructose and its reduction products, 1-deoxyglucitol and 1-deoxymannitol, w...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00665a027
更新日期：1976-10-05 00:00:00
abstract：:Phase partition techniques have been used to measure the binding of the antitumor drugs adriamycin (NSC-123127) and daunorubicin (NSC-82151) to various DNAs. These methods provide reliable equilibrium binding data at the low levels of drug binding that may be expected in vivo. Both adriamycin and daunorubicin exhibit ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00285a033
更新日期：1983-08-02 00:00:00
abstract：:Notwithstanding the relevance of their biological function, slow motions in proteins, beyond the microsecond range, are still poorly understood and often elusive. We propose that acrylamide quenching of Trp phosphorescence of deeply buried residues, when extended over the entire accessible range of lifetime measuremen...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi9009659
更新日期：2009-08-11 00:00:00
abstract：:We have used a photochemical method to map covalent binding sites of the carcinogen benzo[a]pyrenediol epoxide (BPDE) within DNA from the transcriptional control region of the chicken adult beta-globin gene. Our preliminary low-resolution mapping has demonstrated that this region contains highly preferred BPDE binding...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00358a045
更新日期：1986-05-20 00:00:00
abstract：:The conformations of melittin, an amphipathic polypeptide consisting of 26 amino acid residues, and its hydrophobic (residues 1--19) and hydrophilic (residues 20--26) fragments were examined in various solvent systems, including H2O, 2H2O, 2-chloroethanol, and 1,2-dimyristoylphosphatidylcholine (DMPC) multilayers, by ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00539a006
更新日期：1982-05-11 00:00:00
abstract：:SH2 domain-containing inositol 5-phosphatases 1 (SHIP1) and 2 (SHIP2) are structurally similar proteins that catalyze the degradation of lipid secondary messenger phosphatidylinositol 3,4,5-triphosphate to produce phosphatidylinositol 3,4-diphosphate. Despite their high sequence identity (51%), SHIP1 and SHIP2 share l...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi9012462
更新日期：2009-11-24 00:00:00
abstract：:Fluorescence-detected circular dichroism (FDCD) spectra are reported for ethidium in Escherichia coli cells and bound to E. coli DNA in vitro. FDCD bands are observed at 325 and 385 nm. These bands change amplitude as the ethidium to DNA ratio changes. Spectra are similar for in vivo and in vitro measurements. However...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00333a001
更新日期：1985-06-04 00:00:00
abstract：:After protection of cysteine-45 and -82 with iodoacetamide or N-ethylmaleimide, and in the presence of saturating concentrations of substrates, the supernatant isozyme of pig heart aspartate transaminase has been covalently modified at cysteine-390 with 3-bromo-1,1,1-trifluoropropanone. The modified enzyme retains 60-...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00627a004
更新日期：1977-04-19 00:00:00
abstract：:The nontransformed steroid receptors contain several non-steroid binding proteins, such as hsp90, hsp70, and p59. Recently, we and others have shown that p59 (FKBP59) is an immunophilin which binds two potent immunosuppressants, FK506 and rapamycin. This raises the possibility that FK506 or rapamycin may modify the fu...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00201a014
更新日期：1994-09-06 00:00:00
abstract：:Apolipoprotein A-I (apoA-I) is the main protein of plasma high-density lipoproteins (HDL, or good cholesterol) that remove excess cell cholesterol and protect against atherosclerosis. In hereditary amyloidosis, mutations in apoA-I promote its proteolysis and the deposition of the 9-11 kDa N-terminal fragments as fibri...
journal_title：Biochemistry
pub_type： 杂志文章,评审
doi：10.1021/bi2017014
更新日期：2012-01-10 00:00:00
abstract：:Cytochrome P450 3A4 is a drug-metabolizing enzyme of extraordinarily broad substrate specificity. This quality imparts upon the enzyme special importance in understanding its determinants of activity and substrate recognition. Limited successes in P450 3A4 active-site structure studies have been achieved by use of mec...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi049231z
更新日期：2005-02-15 00:00:00
abstract：:Ran, a small nuclear GTP-binding protein, is one of the most abundant Ras-related proteins in eucaryotic cells. Ran is essential for nucleo-cytoplasmatic transport and is primarily localized in the nucleus and at the nuclear pore complex. Here, we characterize the kinetics and equilibrium of the interaction between Ra...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi970524k
更新日期：1997-10-07 00:00:00
abstract：:The factors that govern the substrate reactivity and stereoselectivity of phosphotriesterase (PTE) toward organophosphotriesters containing various combinations of methyl, ethyl, isopropyl, and phenyl substituents at the phosphorus center were determined by systematic alterations in the dimensions of the active site. ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi001549d
更新日期：2001-02-06 00:00:00
abstract：:A cyclic nucleotide phosphodiesterase was extensively purified from the 100000g supernatant fraction of human platelets. The purification was 2500-3000-fold with 30% recovery of activity. The enzyme was isolated by DEAE-cellulose chromatography followed by adsorption to blue dextran-Sepharose and elution with cAMP. Th...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00303a034
更新日期：1984-04-10 00:00:00
abstract：:Mammalian cGMP- and cAMP-dependent protein kinase show considerable similarity in amino acid sequence, although they specifically bind different cyclic nucleotides. Results of cGMP analogue binding experiments, combined with modeling of the cGMP binding sites by analogy to the structure of the homologous catabolite ge...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00440a059
更新日期：1989-07-11 00:00:00
abstract：:Linker histones bind to the nucleosomes and linker DNA of chromatin fibers, causing changes in linker DNA structure and stabilization of higher order folded and oligomeric chromatin structures. Linker histones affect chromatin structure acting primarily through their approximately 100-residue C-terminal domain (CTD). ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi801636y
更新日期：2009-01-13 00:00:00
abstract：:The binding of Zn2+ to tubulin and the ability of this cation to promote the polymorphic assembly of the protein were examined. Equilibrium binding showed the existence of more than 60 potential Zn2+ binding sites on the dimer, including a number of high-affinity sites. The number of high-affinity sites, estimated by ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00270a032
更新日期：1983-01-04 00:00:00
abstract：:Isotope effects have been measured with Mg2+ as the activator and L-malate labeled with deuterium or tritium at carbon 2 as the substrate over the pH range 4-10. Comparison of the nearly pH-independent deuterium-isotope effect on V/Kmalate of 1.5 with the tritium effect of 2.0 by the method of Northrop (Northrop, D.B....
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00623a002
更新日期：1977-02-22 00:00:00
abstract：:Tec family nonreceptor tyrosine kinases are key immunological enzymes that control processes that range from T and B cell development to reorganization of the actin cytoskeleton. The full-length Tec kinases have been resistant to crystallization. This lack of structural data and the paucity of in vitro biochemical dat...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi602512e
更新日期：2007-05-08 00:00:00
abstract：:The cytological architecture of the synaptonemal complex (SC), a meiosis-specific proteinaceous structure, is evolutionarily conserved among eukaryotes. However, little is known about the biochemical properties of SC components or the mechanisms underlying their roles in meiotic chromosome synapsis and recombination. ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi4005528
更新日期：2013-08-06 00:00:00
abstract：:ROS-GC represents a membrane guanylate cyclase subfamily whose distinctive feature is that it transduces diverse intracellularly generated Ca(2+) signals into the production of the second messenger cyclic GMP. An intriguing feature of the first subfamily member, ROS-GC1, is that it is both stimulated and inhibited by ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi990851n
更新日期：1999-09-28 00:00:00
