Abstract：
:Steady-state kinetic studies of the bovine carbonic anhydrase B-catalyzed hydration of CO2, dehydration of HCO3-, and hydrolysis of p-nitrophenylacetate were made in glycerol/water solvents of increased viscosity in order that the effect of diffusion-control on the substrate association reactions could be determined. The minimum association rate constants (kmin = V/(Km[E0])) were obtained at low substrate concentrations. The esterase activity did not depend upon the solvent viscosity. However, both the CO2 hydration and HCO3- dehydration reactions depended upon the solvent viscosity consistent with partial diffusion control. Thus both chemical activation and diffusion control processes contribute to the observed kmin. In low-viscosity aqueous solutions both hydration and dehydration are largely controlled by chemical activation. However, at higher viscosities, equal to that found in the interior of the erythrocyte, both reactions are largely diffusion controlled. This result can be interpreted to mean that carbonic anhydrase is a highly evolved enzyme that has approached its maximum efficiency. The extent of diffusion control observed rules out H2CO3 as a significant reactant with the enzyme. Several models that yield minimum steric requirements for access of substrate to the active site are examined. Minimum steric constraints are less for the smaller CO2. The slower esterase reaction is not influenced by diffusion.
journal_name
Arch Biochem Biophysjournal_title
Archives of biochemistry and biophysicsauthors
Hasinoff BBdoi
10.1016/0003-9861(84)90494-6subject
Has Abstractpub_date
1984-09-01 00:00:00pages
676-81issue
2eissn
0003-9861issn
1096-0384pii
0003-9861(84)90494-6journal_volume
233pub_type
杂志文章abstract：:FHRE-Luc is a promoter reporter construct that is widely used to assess the activity of FoxO (forkhead box, class O) transcription factors. We here demonstrate that this promoter construct responds to exposure of HepG2 human hepatoma cells to known agonists of the aryl hydrocarbon receptor (AhR), 3-methylcholanthrene,...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2011.10.006
更新日期：2011-12-15 00:00:00
abstract：:Desulfovibrio vulgaris rubredoxin, which contains a single [Fe(SCys)4] site, is shown to be a catalytically competent electron donor to two enzymes from the same organism, namely, rubrerythrin and two-iron superoxide reductase (a.k.a. rubredoxin oxidoreductase or desulfoferrodoxin). These two enzymes have been implica...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.2001.2531
更新日期：2001-10-01 00:00:00
abstract：:Human cytochrome CYP3A4 is the most abundant of all the P450s in human liver and is involved in the metabolism of many environmental toxicants and drugs. Kinetic studies with CYP3A4 have been hampered due to low activity of this enzyme obtained from recombinant gene expression systems or difficulty in reconstituting a...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1995.1278
更新日期：1995-05-10 00:00:00
abstract：:Mitochondrial carbonic anhydrase has previously been quantitated in liver mitochondria; it was not detected in guinea pig kidney cortical mitochondria. Evidence of this enzyme in rat kidney cortical mitochondria is reported. Electron microscopy showed that intact mitochondria were free of other intracellular organelle...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(88)90457-2
更新日期：1988-01-01 00:00:00
abstract：:The short term response of the L-6 cell line of rat skeletal myoblasts to elevated extracellular iron concentrations was studied. It was found in all cases that iron as the nitrilotriacetate (NTA) chelate was effective at donating iron to the cells and at stimulating ferritin synthesis. After 48 h in 50 microM ferric ...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(83)90044-9
更新日期：1983-08-01 00:00:00
abstract：:Calcium ion is an uncompetitive inhibitor of the inorganic pyrophosphatases of bovine heart and rat liver mitochondria with respect to substrate MgPPi at pH 8.5 and a non-competitive inhibitor of the former enzyme at pH 7.2. The concentration of Ca2+ required to decrease the maximal velocities for both enzymes at pH 8...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(89)90486-4
更新日期：1989-09-01 00:00:00
abstract：:The keto form of oxaloacetate (OAA), a product of phosphoenolpyruvate carboxylase (PEPC) activity, can undergo various nonenzymatic conversions which make conventional methods of assaying the enzyme difficult, because the products may either act as inhibitors or go undetected. In studies with PEPC isolated from leaves...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(86)90502-3
更新日期：1986-08-01 00:00:00
abstract：:By exploiting its capacity for binding to DNA, the protease inhibitor alpha 1-antichymotrypsin has been isolated from human serum by ammonium sulfate fractionation and successive chromatography on QAE-Sephadex, DNA-cellulose, and Sephacryl S-300. This experimental procedure compares favorably with existing methods for...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(83)90034-6
更新日期：1983-08-01 00:00:00
abstract：:Thrombin induces platelet activation through a variety of intracellular mechanisms, including Ca(2+) mobilization. The protein of the exocytotic machinery SNAP-25, but not VAMPs, is required for store-operated Ca(2+) entry, the main mechanism for Ca(2+) influx in platelets. Hence, we have investigated the role of the ...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2007.04.038
更新日期：2007-09-01 00:00:00
abstract：:We studied the effect of KAR-2 on cytosolic Ca(2+) level in human neutrophils by using a fluorescent dye (Fura-2) trapped in the cells. KAR-2 is a semisynthetic bis-indole derivative that shares vinblastine anti-microtubular properties, but does not share the vinblastine antagonistic effect on calmodulin. Therefore KA...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2013.07.011
更新日期：2013-09-01 00:00:00
abstract：:We have previously shown that exposure of Clone 9 cells to hypoxia, cyanide, or azide results in an acute stimulation of glucose transport that is largely mediated by "activation" of glucose transporter (Glut1) sites preexisting in the plasma membrane. However, it is not known whether inhibition of oxidative phosphory...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1999.1320
更新日期：1999-08-15 00:00:00
abstract：:Through linking inducible cyclooxygenase (COX)-2 with microsomal prostaglandin E2 (PGE2) synthase-1 (mPGES-1), a Single-Chain Enzyme Complex (SCEC, COX-2-10aa-mPGES-1) was engineered to mimic a specific inflammatory PGE2 biosynthesis from omega-6 fatty acid, arachidonic acid (AA), by eliminating involvements of non-in...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2016.04.011
更新日期：2016-08-01 00:00:00
abstract：:While molecular adaptation to high temperature has been extensively studied, the effect of hydrostatic pressure on protein structure and enzymatic activity is still poorly understood. We have studied the influence of pressure on both the quaternary structure and enzymatic activity of the dodecameric TET3 peptidase fro...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2011.07.017
更新日期：2012-01-15 00:00:00
abstract：:The core protein of the large hyaline cartilage proteoglycan, aggrecan, is composed of six distinct domains: globular 1 (G1), interglobular, globular 2 (G2), keratan sulfate attachment, chondroitin sulfate (CS) attachment, and globular 3 (G3). Monoclonal antibodies that recognize epitopes in these domains were raised ...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(92)90421-r
更新日期：1992-11-01 00:00:00
abstract：:Saccharopine dehydrogenase catalyzes the NAD-dependent oxidative deamination of saccharopine to l-lysine and α-ketoglutarate. Lysine 99 is within hydrogen-bond distance to the α-carboxylate of the lysine substrate and D319 is in the vicinity of the carboxamide side chain of NADH. Both are conserved and may be importan...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2011.07.013
更新日期：2011-10-01 00:00:00
abstract：:P-Glycoprotein (Pgp) is an important transport enzyme composed of two homologous domains and transports a wide range of structurally diverse xenobiotics from the cell. Recent studies have indicated that allosteric interactions occur between the nucleotide binding domains and between the substrate binding domains of th...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.2000.2004
更新日期：2000-11-01 00:00:00
abstract：:Tritium-labeled 24(R)-hydroxyvitamin D3 and 24(S)-hydroxyvitamin D3 were chemically synthesized and the 1 alpha-hydroxylation of these compounds by chick kidney homogenates was studied. A marked stereospecific preference with regard to the orientation of the hydroxyl functionality on carbon-24 was noted: while the 24(...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(83)90115-7
更新日期：1983-09-01 00:00:00
abstract：:The neprilysin gene is composed of three distinct 5' noncoding exons which can be joined to the first coding exon to generate multiple mRNA species, all encoding the same protein. Genomic fragments containing upstream sequences of each of these three noncoding exons from the rat neprilysin gene were subcloned in the p...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1998.0855
更新日期：1998-10-01 00:00:00
abstract：:The extrahepatic expression of UDP-glucuronosyltransferases (UGTs) is important in the detoxification of a number of endogenous and exogenous compounds, including 5-hydroxytryptamine and morphine. Studies were designed to investigate the extrahepatic expression of human UGTs using RT-PCR techniques and to determine th...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1999.1155
更新日期：1999-05-01 00:00:00
abstract：:Cortactin is an F-actin binding protein that contributes to cytoskeleton remodelling. We identified five isoforms of mouse cortactin that differ in the number of tandem 37-amino acid repeats, named cortactin repeats. The transcription of minor isoforms with 4.5, 3.5 or 2.5 cortactin repeats was low in most adult tissu...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2004.04.015
更新日期：2004-07-01 00:00:00
abstract：:The rat enhancer of split- and hairy-related protein-2 (SHARP-2) is a basic helix-loop-helix transcription factor. The hepatic expression of SHARP-2 mRNA was investigated under various conditions. The level was decreased in the regenerating rat liver and malignant hepatoma cells. In contrast, the expression of SHARP-2...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2003.11.011
更新日期：2004-02-01 00:00:00
abstract：:The effects of pH, NaCl, and malate2- on the equilibrium between dimeric and higher-molecular-weight forms of NAD malic enzyme from Solanum tuberosum var. Chieftain have been analyzed by monitoring the kinetic changes associated with disaggregation [S. D. Grover and R. T. Wedding (1982) Plant Physiol. 70, 1169-1172]. ...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(84)90288-1
更新日期：1984-11-01 00:00:00
abstract：:The time-course kinetics of the cytochrome P-450-catalyzed dealkylations of the exogenous compounds benzphetamine, ethylmorphine, codeine, and 7-ethoxycoumarin were compared to the hydroxylation of the endogenous compound testosterone. Using liver microsomes from phenobarbital-induced rats, the time course of the deme...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(83)90249-7
更新日期：1983-07-15 00:00:00
abstract：:(+)-Menthofuran is an undesirable monoterpenoid component of peppermint (Mentha x piperita) essential oil that is derived from the alpha,beta-unsaturated ketone (+)-pulegone. Microsomal preparations, from the oil gland secretory cells of a high (+)-menthofuran-producing chemotype of Mentha pulegium, transform (+)-pule...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.2001.2378
更新日期：2001-06-15 00:00:00
abstract：:Altered iso-1- and iso-2-cytochromes c, with certain amino acid replacements, occur at diminished levels due to degradation in the yeast Saccharomyces cerevisiae. A subclass of the labile isocytochromes c are significantly protected from degradation by the presence of cytochromes a.a3 and c1, the physiological partner...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1998.0591
更新日期：1998-04-01 00:00:00
abstract：:Previous studies demonstrated that liver microsomes from untreated rats catalyze the omega, omega-1, and omega-2 hydroxylation of prostaglandins [K. A. Holm, R. J. Engell, and D. Kupfer (1985) Arch. Biochem. Biophys. 237, 477-489]. The current study examined the regioselectivity of hydroxylation of PGE1 and PGE2 by pu...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(88)90117-8
更新日期：1988-02-15 00:00:00
abstract：:The enzyme phenylalanine hydroxylase catalyzes the hydroxylation of excess phenylalanine in the liver to tyrosine. The enzyme is regulated allosterically by phenylalanine and by phosphorylation of Ser16. Hydrogen/deuterium exchange monitored by mass spectrometry has been used to gain insight into any structural change...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2013.03.006
更新日期：2013-07-15 00:00:00
abstract：:Atrial muscles of the heart are known to produce polypeptide hormones called atrial natriuretic factors (ANF) which have potent diuretic and hypotensive action. These hormones are synthesized as a larger protein precursor called pro atrial natriuretic factor or proANF which contains the biologically active ANF sequenc...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(89)90294-4
更新日期：1989-06-01 00:00:00
abstract：:Phosphate-dependent glutaminase is associated with the inner membrane of rat renal mitochondria. The orientation of this enzyme was characterized by comparing its sensitivity in isolated mitochondria and in mitoplasts to two membrane impermeable inhibitors. Mitoplasts were prepared by repeated swelling of mitochondria...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(85)90767-2
更新日期：1985-11-15 00:00:00
abstract：:Nanoceria were synthesized by discharging plasma at 800 V with a frequency of 30 kHz for 0-25 min using a pulsed unipolar power supply into solutions containing 1 or 2 mM of Ce(NO3)2. UV-Vis spectroscopy showed a characteristic absorbance maxima at 304-320 nm for the nanoceria with increase in the intensity of the pea...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2018.02.003
更新日期：2018-05-01 00:00:00
