Abstract：
:Biosynthesis of thyroxine in the thyroid gland involves a reaction between two diiodotyrosyl residues within the same molecule of thyroglobulin, a large, thyroid-specific glycoprotein. This reaction, generally referred to as the coupling reaction, is catalyzed in the thyroid by the heme-containing glycoprotein enzyme, thyroid peroxidase, also a thyroid-specific protein. The coupling reaction is, however, not specific for thyroid peroxidase; it is also efficiently catalyzed by other heme-containing peroxidases. Peroxidase-catalyzed coupling may also occur between a monoiodotyrosyl and a diiodotyrosyl residue in thyroglobulin to form the more potent thyroid hormone, 3',3,5-triiodothyronine. Under most conditions, thyroxine formation in the thyroid is greatly favored over that of 3',3,5-triiodothyronine. Two mechanisms have been proposed for the coupling reaction, a radical mechanism and an ionic mechanism. In this, and in the following paper, we present evidence favoring a radical mechanism. This view is bsed primarily on the observation that peroxidase-catalyzed coupling is markedly stimulated by substoichiometric concentrations of free diiodotyrosine (DIT). Evidence obtained in this and in the following paper leads us to conclude that the stimulatory effect of DIT on coupling involves peroxidase-catalyzed oxidation of the added DIT to a radical form. We propose that this stimulation involves a radical chain propagation mechanism. This implies that peroxidase-catalyzed coupling in the absence of DIT must also be a radical-mediated reaction.
journal_name
Arch Biochem Biophysjournal_title
Archives of biochemistry and biophysicsauthors
Taurog A,Dorris M,Doerge DRdoi
10.1006/abbi.1994.1474subject
Has Abstractpub_date
1994-11-15 00:00:00pages
82-9issue
1eissn
0003-9861issn
1096-0384pii
S0003-9861(84)71474-3journal_volume
315pub_type
杂志文章abstract：:A deficiency in microsomal glucose-6-phosphatase (G6Pase) activity causes glycogen storage disease type 1 (GSD-1), a clinically and biochemically heterogeneous group of diseases. It has been suggested that catalysis by G6Pase involves multiple components, with defects in the G6Pase catalytic unit causing GSD-1a and de...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1998.0849
更新日期：1998-10-01 00:00:00
abstract：:The mammalian aldehyde dehydrogenase-3 gene (ALDH3) exhibits several aspects of tissue-specific expression. Certain normal tissues, such as the cornea, constitutively express ALDH3 at very high levels. Other tissues, such as normal liver, do not express ALDH3. In liver, ALDH3 is inducible by polycyclic aromatic hydroc...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1998.0989
更新日期：1999-01-15 00:00:00
abstract：:Dihydrocaffeic acid, a dietary constituent and a microbial metabolite of flavonoids, is an antioxidant, but few biological effects have been examined. After its production by microflora in the colon, dihydrocaffeic acid is absorbed and found in plasma as a combination of free and metabolized forms. Excess solar UV rad...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2008.01.019
更新日期：2008-08-15 00:00:00
abstract：:Oligopeptidase A (OpdA) belongs to the M3A subfamily of bacterial peptidases with catalytic and structural properties similar to mammalian thimet-oligopeptidase (TOP) and neurolysin (NEL). The three enzymes have four conserved Tyr residues on a flexible loop in close proximity to the catalytic site. In OpdA, the flexi...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2010.05.025
更新日期：2010-08-15 00:00:00
abstract：:The role of the conserved sequence motif 301DDLTDP306 in the F0F1 ATP synthase beta subunit was assessed by mutagenic analysis in the Escherichia coli enzyme. Mutations gave variable effects on F1 sector activity, stability, and membrane binding to the F0 sector. Upon solubilization, F1 sectors of the betaD302E and be...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1998.0856
更新日期：1998-10-15 00:00:00
abstract：:Concentrations of GDP, which are expected to bind to the catalytic site and inhibit the autophosphorylation of succinyl-CoA synthetase (SCS) when NTP is used as a substrate, were found to increase the level of phosphoenzyme formed. The ability of GDP to do so is dependent upon the presence of a protein distinct from S...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1997.0313
更新日期：1997-11-01 00:00:00
abstract：:This article is an essay that discusses the concepts underlying the application of modern transition state theory to reactions in enzymes. Issues covered include the potential of mean force, the quantization of vibrations, the free energy of activation, and transmission coefficients to account for nonequilibrium effec...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章,评审
doi：10.1016/j.abb.2015.05.004
更新日期：2015-09-15 00:00:00
abstract：:Advances in management have resulted in a dramatic decline in mortality for individuals infected with human immunodeficiency virus (HIV). This decrease in mortality, initially the result of improved prophylaxis and treatment of opportunistic infections but later mediated by the use of highly-active antiretroviral ther...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章,评审
doi：10.1016/j.abb.2010.07.029
更新日期：2010-11-01 00:00:00
abstract：:An increased permeability of the intestinal barrier is proposed as a major event in the pathophysiology of inflammatory bowel diseases (IBD). Tumor necrosis alpha (TNFα) plays a central role in IBD pathogenesis, in part promoting tight function (TJ) barrier dysfunction. Food extracts enriched in (-)-epicatechin (EC) p...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2015.01.024
更新日期：2015-05-01 00:00:00
abstract：:Diabetic surgical patients are at risk for peri- and post-operative complications, which can be prevented by maintaining tight glycemic control during anesthesia. Control of blood sugar would decrease unwanted chemical reactions, such as protein glycation, minimizing tissue dysfunction. Methylglyoxal (MG) is a major c...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2010.04.001
更新日期：2010-06-01 00:00:00
abstract：:Recombinant CYP4F8 and CYP4F12 metabolize prostaglandin H2 (PGH2) analogs by omega2- and omega3-hydroxylation and arachidonic acid (20:4n-6) by omega3-hydroxylation. CYP4F8 was found to catalyze epoxidation of docosahexaenoic acid (22:6n-3) and docosapentaenoic acid (22:5n-3) and omega3-hydroxylation of 22:5n-6. CYP4F...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2005.07.003
更新日期：2005-09-15 00:00:00
abstract：:A type II ribosome-inactivating protein (RIP) was isolated from the bark tissue of Japanese elderberry (Sambucus sieboldiana) and named sieboldin-b. Sieboldin-b is a heterodimeric protein consisting of 27- and 33-kDa subunits and showed strong ribosome-inactivating activity in vitro but did not show in vivo toxicity. ...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1997.9927
更新日期：1997-04-15 00:00:00
abstract：:During the metabolism of 1,2-dimethylhydrazine (a colon carcinogen) in rats, methyl radicals (.CH3) are produced. To gain an insight into the nature of .CH3 interactions with biomolecules in vivo, we conducted in vitro studies using RNA as a model compound. RNA was incubated in a system where .CH3 was generated from t...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1993.1497
更新日期：1993-10-01 00:00:00
abstract：:Podocytes and their foot processes interlinked by slit diaphragms, constitute a continuous outermost layer of the glomerular capillary and seem to be crucial for maintaining the integrity of the glomerular filtration barrier. Purinergic signaling is involved in a wide range of physiological processes in the renal syst...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2020.108649
更新日期：2020-11-30 00:00:00
abstract：:Insulin has pleiotropic effects on sensitive cells, including the regulation of specific mRNA accumulation initiated by the binding of insulin to its plasma membrane receptor. Lectins, such as wheat germ agglutinin (WGA) and concanavalin A (Con A), are known to be insulin mimetic. It is thought that WGA and Con A inte...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(87)90086-5
更新日期：1987-04-01 00:00:00
abstract：:A 1.6-kb cDNA clone was isolated by screening a library prepared from chick corneal mRNA with a cDNA clone to bovine decorin. The cDNA contained an open reading frame coding for a M(r) 39,683 protein. A 19-amino-acid match with sequence from the N-terminus of core protein from the corneal chondroitin/dermatan sulfate ...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(92)90562-b
更新日期：1992-07-01 00:00:00
abstract：:In order to characterize cellular retinoic acid-binding protein (CRABP) from chick embryos, we resolved the [3H]RA-binding activity of embryo extracts by Mono Q anion-exchange chromatography. Fractions containing [3H]RA-binding proteins eluted in two peaks at 7 and 10 min with the latter showing 10-fold higher activit...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1996.0553
更新日期：1996-12-15 00:00:00
abstract：:alpha 1-Acid glycoprotein (alpha 1-AGP) is a glucocorticoid inducible gene product that is synthesized and secreted by certain rat hepatoma tissue culture (HTC) cell lines such as M1.54. Exposure to monensin, a Na+-K+ ionophore, causes a significant redistribution of alpha 1-AGP into two distinct fractions; immunoprec...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(86)90491-1
更新日期：1986-04-01 00:00:00
abstract：:Purification of the scrapie agent by methods using digestion with proteinase K yields a protein product, PrP-27-30, with an apparent mass of 27-30 kDa (D. C. Bolton et al. (1982) Science 218, 1309-1311; S. B. Prusiner et al. (1982) Biochemistry 21, 6942-6950). In contrast, a 33-37 kDa glycoprotein, HaSp33-37, was the ...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(87)90380-8
更新日期：1987-11-01 00:00:00
abstract：:An in vitro expression plasmid (pGRAP) that contained the cDNA coding for the rat mitochondrial aldehyde dehydrogenase precursor was constructed, mRNA was synthesized then translated, and the in vitro synthesized precursor of aldehyde dehydrogenase was used in an in vitro import assay. As expected the 19 amino acid si...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(89)90238-5
更新日期：1989-08-01 00:00:00
abstract：:Actinomycin D (act-D) anchors itself into DNA-base pairs by intercalation and thereby inhibits mRNA synthesis. It has been well established that act-D elicits apoptosis in various cell types involving endothelial cells. However, the regulatory mechanisms of actinomycin D-induced apoptotic cell death still remain uncle...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2004.03.028
更新日期：2004-05-15 00:00:00
abstract：:Bovine pancreatic trypsin inhibitor (BPTI) and tick anticoagulant peptide (TAP) are two structurally homologous proteins, which have been shown to exhibit distinct mechanisms of oxidative folding. We demonstrate here differences of their folding properties using the technique of disulfide scrambling. Two extensively u...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2005.02.031
更新日期：2005-05-01 00:00:00
abstract：:A radioimmunoassay was developed to assess the response of testicular HO-1 to agents known to increase the microsomal heme oxygenase activity. Treatment of rats with human chorionic gonadotropin (hCG) increased the microsomal heme oxygenase activity in rat testis. The following data suggest that the increase was speci...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(89)90569-9
更新日期：1989-01-01 00:00:00
abstract：:To evaluate the conformation of reduced HEL, the monoclonal antibodies HyC1 and HyC2, which recognize different conformational epitopes on native hen egg lysozyme (HEL), were used, and the kinetics of their interactions with native HEL, S-1,2-dicarboxyethylated HEL (DCE-HEL), and carboxymethylated Cys6 and Cys127 HEL ...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2009.11.024
更新日期：2010-02-15 00:00:00
abstract：:Treatment of streptozotocin (ST), tumor necrosis factor-alpha (TNF-alpha), and interleukin-1beta (IL-1beta) resulted in destroying insulin-secreting beta-cells of pancreatic islets and impairment of islet glucose oxidation and glucose-induced insulin secretion. IL-1beta and TNF-alpha inhibited insulin release and gluc...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1998.1004
更新日期：1999-02-15 00:00:00
abstract：:Csk is a protein tyrosine kinase that phosphorylates other protein tyrosine kinases of the Src family and down-regulates their activities. It is not known how Csk is regulated. We investigated the possibility that Csk is regulated through phosphorylation by examining if Csk can serve as an in vitro substrate for a pan...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1997.0156
更新日期：1997-07-15 00:00:00
abstract：:The catalytic activity of glyceraldehyde 3-phosphate dehydrogenase (GAPDH) decreased (almost linearly) as a function of increasing concentrations of tubulin; the total loss in activity was attained at a ratio of 1.2 to 1.8 tubulin dimer to GAPDH tetramer. Based on the inhibition data, a dissociation constant for the t...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1994.1385
更新日期：1994-09-01 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 St-20 and ST-40 cDNAs encode rat liver hydroxysteroid sulfotransferases (HS-ST) that are 90% identical in amino acid sequence but exhibit different substrate preferences for dehydroepiandrosterone (DHEA), androsterone (AD), and cortisol (CS). ST-40 is active for all three substrates, whereas ST-20 is mainly active...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1997.9979
更新日期：1997-05-15 00:00:00
abstract：:The structures of the sugar kinase/heat shock 70/actin superfamily of enzymes show that the active site is located in a deep cleft between two domains whose relative movement defines a domain closure conformational change thought to be involved in the catalytic and regulatory properties of members of the superfamily. ...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1997.0444
更新日期：1998-01-15 00:00:00
