Abstract:
:Dihydrouridine is absent from the tRNA of almost all hyperthermophiles and most Archaea but is ubiquitous in the tRNA of Eubacteria and Eukaryotes. In order to investigate whether this could be due to instability, the rate of ring opening of dihydrouridine was measured between 25 and 120 degrees C. The dihydrouridine ring is stable at 25 degrees C, but the half-life at 100 degrees C and pH 7 is 9.1 h, which is comparable to the doubling time of hyperthermophiles. This suggests an explanation for the absence of dihydrouridine from the tRNA of hyperthermophiles. The rates of ring opening of dihydrouracil, dihydrothymine, and 1-N-methyldihydrouracil were measured at 100 degrees C and pH 6-9, as were the equilibrium constants for ring closure of the ureido acids to the dihydrouracils. The pH rate profiles for ring opening and ring closing were calculated from the data. Possible roles for dihydrouracils in the pre-RNA world are discussed.
journal_name
Biochemistryjournal_title
Biochemistryauthors
House CH,Miller SLdoi
10.1021/bi951577+subject
Has Abstractpub_date
1996-01-09 00:00:00pages
315-20issue
1eissn
0006-2960issn
1520-4995pii
bi951577+journal_volume
35pub_type
杂志文章相关文献
BIOCHEMISTRY文献大全abstract::Eukaryotic proteins with carboxyl-terminal CaaX motifs undergo three post-translational processing reactions-protein prenylation, endoproteolysis, and carboxymethylation. Two genes in yeast encoding CaaX endoproteases, AFC1 and RCE1, have been identified. Rce1p is solely responsible for proteolysis of yeast Ras protei...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi9923611
更新日期:2000-04-11 00:00:00
abstract::The role of histidine in catalysis by prostaglandin H synthase has been investigated using chemical modification with diethyl pyrocarbonate (DEPC), an agent that has been found to rather selectively derivatize histidine residues in proteins under mild conditions. Incubation of the synthase apoprotein with DEPC at pH 7...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00124a013
更新日期:1992-03-10 00:00:00
abstract::The lipid A disaccharide of the Escherichia coli envelope is synthesized from the two fatty acylated glucosamine derivatives UDP-N2,O3-bis[(R)-3-hydroxytetradecanoyl]-alpha-D- glucosamine (UDP-2,3-diacyl-GlcN) and N2,O3-bis[(R)-3-hydroxytetradecanoyl]-alpha-D-glucosamine 1-phosphate (2,3-diacyl-GlcN-1-P) [Ray, B. L., ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00406a017
更新日期:1988-03-22 00:00:00
abstract::The kinetics of ATP-induced Ca2+ uptake by vesicular dispersions of sarcoplasmic reticulum were determined with a time resolution of about 10 ms, depending on the temperature. Ca2+ uptake was initiated by the addition of ATP through the flash photolysis of P3-1-(2-nitrophenyl)-ethyl adenosine 5'-triphosphate utilizing...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00292a003
更新日期:1983-11-08 00:00:00
abstract::Calcium dynamics and its linked molecular interactions cause a variety of biological responses; thus, exploiting techniques for detecting both concurrently is essential. Here we describe a method for measuring the cytosolic Ca(2+) concentration ([Ca(2+)](i)) and protein-protein interactions within the same cell, using...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi200287x
更新日期:2011-05-31 00:00:00
abstract::The function of the GM2 activator protein is to act as a substrate-specific cofactor in the hydrolysis of GM2 ganglioside by beta-hexosaminidase A. Mutations in the gene encoding it result in the AB variant form of GM2 gangliosidosis. One such mutation, Cys138 Arg, results in the mutant protein being retained and degr...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi971211s
更新日期:1998-01-20 00:00:00
abstract::Previous work has indicated that following the rapid adenosine 5'-triphosphate (ATP) induced dissociation of the microtubule-dynein complex, the rate-limiting step in the ATPase cycle is product release [Johnson, K. A. (1983) J. Biol. Chem. 258, 13825-13832], which occurs at a rate of approximately 2-6 s-1. In this re...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00350a022
更新日期:1986-01-28 00:00:00
abstract::alpha-Glucosidase (EC 3.2.1.20) was purified to homogeneity from logarithmically growing cells of Saccharomyces carlsbergensis. The purification involved the following steps: (a) ammonium sulfate fractionation; (b) Sephadex G-100 chromatography; (c) DEAE-cellulose chromatography; and (d) hydroxylapatite chromatography...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00615a011
更新日期:1978-10-31 00:00:00
abstract::Fragile X syndrome, the most common cause of inherited mental retardation, is caused by the absence of the fragile X mental retardation protein (FMRP). The emerging picture is that FMRP is involved in repression of translation through a complex network of protein-protein and protein-RNA interactions. Very little struc...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi034909g
更新日期:2003-09-09 00:00:00
abstract::Recently, a new clathrin assembly protein (AP180) has been purified from coated vesicles of bovine brain (Ahle & Ungewickell, 1986). This protein has been shown to promote polymerization of clathrin into a homogeneous population of baskets under conditions where pure clathrin does not polymerize by itself. We have pur...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00416a040
更新日期:1988-08-09 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::The bacterial photosynthetic reaction center is the evolutionary ancestor of the Photosystem II reaction center. These proteins share the same fold and perform the same biological function. Nevertheless, the details of their molecular reaction mechanism differ. It is of significant biological and biochemical interest ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi802033k
更新日期:2009-02-17 00:00:00
abstract::Calcium is required for the substrate binding and for the chemical step of the interfacial catalytic turnover cycle of pancreatic phospholipase A2 (PLA2), but not for the binding of the enzyme to the interface. The role of calcium and other divalent cations (C) is analyzed for the effect on the substrate binding and k...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi9728607
更新日期:1998-09-08 00:00:00
abstract::We have used resonance energy transfer to read out the interactions of the alpha subunit of transducin (alpha T) with the transducin beta gamma subunit complex (beta gamma T) and to compare the rate of aluminum fluoride-induced alpha T activation, as reflected by the enhancement of the alpha T tryptophan fluorescence,...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00199a046
更新日期:1994-08-23 00:00:00
abstract::Despite significant progress in the past decade, questions still remain about the complete structural, dynamic, and thermodynamic effect of the cis-syn cyclobutane pyrimidine dimer lesion (hereafter called the thymine dimer) on double-stranded genomic DNA. We examined a 19-mer oligodeoxynucleotide duplex containing a ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi801417u
更新日期:2008-12-09 00:00:00
abstract::Lactose repressor protein, regulator of lac enzyme expression in Escherichia coli, maintains its structure and function at extremely low protein concentrations (<10(-)12 M). To examine the unfolding and dissociation of this tetrameric protein, structural transitions in the presence of varying concentrations of urea we...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi9900727
更新日期:1999-05-18 00:00:00
abstract::The ratio of the second-order rate constants for reduction of dihydroxyacetone phosphate (DHAP) and of the neutral truncated substrate glycolaldehyde (GLY) by glycerol 3-phosphate dehydrogenase (NAD (+), GPDH) saturated with NADH is (1.0 x 10 (6) M (-1) s (-1))/(8.7 x 10 (-3) M (-1) s (-1)) = 1.1 x 10 (8), which was u...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi8001743
更新日期:2008-04-22 00:00:00
abstract::A time-resolved microscope fluorimeter based on a synchroscan streak camera and a fast pulsed laser system has been developed to measure the fluorescence lifetime decay under the fluorescence microscope. This system allows one to measure the nanosecond fluorescence lifetimes of fluorophores in a small spot (0.8-6.3 mi...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00240a024
更新日期:1991-07-02 00:00:00
abstract::Heme-regulated eIF2alpha kinase [heme-regulated inhibitor (HRI)] plays a critical role in the regulation of protein synthesis by heme iron. The kinase active site is located in the C-terminal domain, whereas the N-terminal domain is suggested to regulate catalysis in response to heme binding. Here, we found that the r...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi060556k
更新日期:2006-08-15 00:00:00
abstract::Glycosylases specifically recognize and flip their target base out of the DNA helix into the enzyme's active site. Our simulations show that a partially flipped state, already present in free DNA carrying a T:G mispair, becomes the more probable state compared to the closed state after binding of thymine DNA glycosyla...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.8b00409
更新日期:2018-10-02 00:00:00
abstract::Nucleotide excision repair (NER) is a crucial pathway in the maintenance of genome stability requiring at least two dozen proteins. XPA and RPA have essential roles in the damage recognition step of NER. To better understand the mechanism of their interactions with DNA, we utilized equilibrium and stop-flow kinetic ap...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi011041q
更新日期:2002-01-08 00:00:00
abstract::Oligomerization of numerous G protein-coupled receptors has been documented, including the prototypic family B secretin receptor. The clinical significance of oligomerization of this receptor became clear with the recent observation that a misspliced form present in pancreatic cancer could associate with the wild-type...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi060494y
更新日期:2006-07-11 00:00:00
abstract::The fluorescence intensity of the two flavin prosthetic groups, FMN and FAD, in neuronal nitric oxide synthase (nNOS) was found to decay highly nonexponentially, being best described by four fluorescence lifetimes. This excited state heterogeneity is the result of multiple flavin quenching sites which are due to sever...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi981138l
更新日期:1998-12-15 00:00:00
abstract::The rapid expansion of the amount of genomic and structural data has provided many examples of enzymes with evolutionarily related active sites that catalyze different reactions. Functional comparisons of these active sites can provide insight into the origins of the enormous catalytic proficiency of enzymes and the e...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi060847t
更新日期:2006-08-15 00:00:00
abstract::Amyloid deposition of human islet amyloid polypeptide (hIAPP) in the islets of Langerhans is closely associated with the pathogenesis of type II diabetes mellitus. Despite substantial evidence linking amyloidogenic hIAPP to loss of β-cell mass and decreased pancreatic function, the molecular mechanism of hIAPP cytotox...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi300542g
更新日期:2012-09-04 00:00:00
abstract::Serine hydroxymethyltransferase (SHMT) catalyzes the reversible conversion of l-serine and tetrahydrofolate into glycine and 5,10-methylenetetrahydrofolate. This enzyme, which plays a pivotal role in one-carbon metabolism, is involved in cancer metabolic reprogramming and is a recognized target of chemotherapy interve...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.8b01074
更新日期:2018-12-26 00:00:00
abstract::RNA binding proteins play an important role in regulating alternative pre-mRNA splicing and in turn cellular gene expression. Many of these RNA binding proteins occur as gene families with members sharing a high degree of primary structure identity and domain organization yet have tissue-specific expression patterns a...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.8b00256
更新日期:2018-07-03 00:00:00
abstract::Sarcoplasmic phosphorylase phosphatase extracted from ground skeletal muscle was recovered in a high molecular weight from (Mr = 250000). This enzyme has been purified from extracts by anion-exchange and gel chromatography to yield a preparation with three major protein components of Mr 83000, 72000, and 32000 by sodi...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00566a019
更新日期:1980-12-09 00:00:00
abstract::The preferential interactions of proteins with solvent components were studied in concentrated aqueous solutions of the sulfate, acetate, and chloride salts of Mg2+, Ba2+, Ca2+, Mn2+ and Ni2+ [except for CaSO4, BaSO4, Mn-(OAc)2, and Ni(OAc)2], and results were compared with those of the Na+ salts. It was found that, f...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00320a004
更新日期:1984-12-04 00:00:00
abstract::Nicotinic acid phosphoribosyltransferase (NAPRTase; EC 2.4.2.11) forms nicotinic acid mononucleotide (NAMN) and PPi from 5-phosphoribosyl 1-pyrophosphate (PRPP) and nicotinic acid (NA). The Vmax NAMN synthesis activity of the Salmonella typhimurium enzyme is stimulated about 10-fold by ATP, which, when present, is hyd...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi9720134
更新日期:1998-03-24 00:00:00