Abstract：
:The phytoene desaturase CrtI from Rubrivivax gelatinosus catalyzes simultaneously a three- and four-step desaturation producing both neurosporene and lycopene. These carotenes are intermediates for the synthesis of spheroidene and spirilloxanthin, respectively. Two different mutation libraries for the crtI gene from R. gelatinosus were constructed to screen for modified enzymes which synthesize almost exclusively either neurosporene or lycopene. The resulting mutants carried between one and four amino acid exchanges and at least one of them affected the secondary protein structure by shortening or extending one of the helices. A prominent amino acid which was exchanged in the neurosporene or lycopene-forming desaturase was leucine 208. Enzyme kinetic studies were carried out with the L208 modified desaturase and the specificities for phytoene and neurosporene as substrates determined. Higher and lower values correlate well with the higher or lower potential for the synthesis of lycopene from neurosporene. TopPred analysis of the mutations of L208 indicated that the location is in a highly hydrophobic membrane-integrated region which is a good candidate for the substrate-binding site of the desaturase.
journal_name
Arch Biochem Biophysjournal_title
Archives of biochemistry and biophysicsauthors
Stickforth P,Sandmann Gdoi
10.1016/j.abb.2010.09.021subject
Has Abstractpub_date
2011-01-01 00:00:00pages
118-22issue
1eissn
0003-9861issn
1096-0384pii
S0003-9861(10)00413-3journal_volume
505pub_type
杂志文章abstract：:The role of chalcone synthase in the regulation of flavonoid biosynthesis during organogenesis of oat primary leaves has been investigated at the level of enzyme activity and mRNA translation in vitro. Chalcone synthase was purified about 500-fold. The apparent Km values were 1.5 and 6.3 microM for 4-coumaroyl-CoA and...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(86)90738-1
更新日期：1986-11-01 00:00:00
abstract：:Raspberries are a rich source of ellagitannins and anthocyanins. The aim of this work was to investigate whether raspberry consumption can improve vascular function and to understand which phenolic metabolites may be responsible for the effects. A 3 arm double-blind randomized controlled crossover human intervention t...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章,随机对照试验
doi：10.1016/j.abb.2018.05.016
更新日期：2018-08-01 00:00:00
abstract：:Geranylgeranyl diphosphate synthase supplies the essential acyclic precursor for Taxol biosynthesis in methyl jasmonate-induced Taxus canadensis suspension cell cultures. A cDNA encoding this prenyltransferase was cloned from an induced T. canadensis cell library. The recombinant enzyme expressed in yeast was confirme...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1998.0926
更新日期：1998-12-01 00:00:00
abstract：:In the Escherichia coli class Ia ribonucleotide reductase (RNR), the best characterized RNR, there is no spectroscopic evidence for the existence of the postulated catalytically essential thiyl radical (R-S(*)) in the substrate binding subunit R1. We report first results on artificially generated thiyl radicals in R1 ...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.2001.2658
更新日期：2002-01-01 00:00:00
abstract：:Methyl pyruvate was found to exert a dual effect on insulin release from isolated rat pancreatic islets. A positive insulinotropic action prevailed at low concentrations of D-glucose, in the 2.8 to 8.3 mM range, and at concentrations of the ester not exceeding 10.0 mM. It displayed features typical of a process of nut...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1996.0504
更新日期：1996-11-15 00:00:00
abstract：:Carotenoids possessing hydroxyl groups can be found in nature both as free xanthophylls and as carotenoid esters, i.e. acylated with fatty acids. A single carotenoid can be acylated with different fatty acids, resulting in a high number of possible structures of carotenoid esters. The analysis of carotenoid esters can...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章,评审
doi：10.1016/j.abb.2018.04.005
更新日期：2018-06-15 00:00:00
abstract：:M. Kuwajima, C. B. Newgard, D. W. Foster, and J. D. McGarry (1986, J. Biol. Chem. 261, 8849-8853) have concluded that the reason postprandial hepatic glycogenesis occurs primarily from gluconeogenic precursors rather than glucose is because glucokinase activity is insufficient to support the observed rates of glycogen...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(87)90648-5
更新日期：1987-02-15 00:00:00
abstract：:Nonspecific lipid transfer protein (sterol carrier protein2) has previously been proposed to function as (i) a catalyst for intracellular movement of newly synthesized phospholipid, (ii) a cofactor in the biosynthesis and metabolism of cholesterol, and (iii) a cofactor in the feedback inhibition of cholesterol synthes...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(85)90385-6
更新日期：1985-08-15 00:00:00
abstract：:A 1.1-kb Hp alpha I fragment of the Escherichia coli chromosome containing the gene for translation initiation factor 3 was employed as a probe in heterologous hybridization to chromosomal DNA from a variety of other procaryotes. Positive hybridization was observed to DNA derived from all gram-negative bacteria tested...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(84)90276-5
更新日期：1984-11-15 00:00:00
abstract：:Because of the severe limitations on growing large quantities of Drosophila affinidisjuncta in the laboratory, direct purification of alcohol dehydrogenase (ADH) from this species has proven impossible. As an alternative source of this enzyme, a cDNA encoding functional ADH was isolated from a newly constructed cDNA l...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(89)90503-1
更新日期：1989-09-01 00:00:00
abstract：:Cellobiose dehydrogenase (CDH), an extracellular hemoflavoenzyme produced by the cellulose-degrading cultures of Phanerochaete chrysosporium, oxidizes cellobiose to cellobionolactone. CDH has been purified to homogeneity by a five-step purification procedure. The homogeneous CDH is monomeric and has a relative molecul...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1993.1098
更新日期：1993-02-01 00:00:00
abstract：:The effects of testosterone propionate (TP) on the oxidative stress and mitochondrial function, as well as on mitochondria associated apoptotic signaling, were analyzed in the gastric mucosa in orchiectomized male rats. The present study showed that testosterone deficiency triggered apoptosis by damaging the mitochond...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2018.05.002
更新日期：2018-07-01 00:00:00
abstract：:The interactions between various dietary cancer chemopreventive phytochemicals in drug transporter functions are not well studied. In this study, the effects of genistein and resveratrol on the multidrug resistance protein 2 (MRP2) expression and the underlying molecular mechanisms were investigated using HepG2-C3 cel...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2011.06.004
更新日期：2011-08-15 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：:Sepsis is a life-threatening clinical syndrome defined as a deregulated host response to infection associated with organ dysfunction. Mechanisms underlying the pathophysiology of septic liver dysfunction are incompletely understood. Among others, the iron containing tetrapyrrole heme inflicts hepatic damage when relea...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2019.108075
更新日期：2019-09-15 00:00:00
abstract：:A marine snail digestive phospholipase A2 (mSDPL) was purified from delipidated hepatopancreas. Unlike known digestive phospholipases A2, which are 14 kDa proteins, the purified mSDPL has a molecular mass of about 30 kDa. It has a specific activity of about 180 U/mg measured at 50 degrees C and pH 8.5 using phosphatid...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2009.11.020
更新日期：2010-02-15 00:00:00
abstract：:Total liver poly(A+)-RNA isolated from untreated, and 3-methylcholanthrene-, trans-stilbene oxide-, and phenobarbital-treated rats has been translated in the rabbit reticulocyte lysate system in order to determine the effect of these xenobiotics on the level of translationally active DT-diaphorase mRNA. The in vitro t...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(84)90556-3
更新日期：1984-07-01 00:00:00
abstract：:Phenolic phytochemicals such as tannins, which are natural constituents of green tea, red wine, and other plant products, are considered to have cancer-preventive properties. An important endogenous mediator of tumorigenesis is the nuclear enzyme poly(ADP-ribose) polymerase 1 (PARP-1). PARP-1 synthesizes polymers of A...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2004.02.024
更新日期：2004-05-01 00:00:00
abstract：:Thromboxane A2 synthase (TXAS) binds to the endoplasmic reticulum membrane and catalyzes both an isomerization of prostaglandin H2 (PGH2) to form thromboxane A2 (TXA2) and a fragmentation of PGH2 to form 12-hydroxy-5,8,10-heptadecatrienoic acid (HHT) and malondialdehyde (MDA). TXAS is a non-classic cytochrome P450 in ...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/s0003-9861(03)00287-x
更新日期：2003-08-01 00:00:00
abstract：:If liver alcohol dehydrogenase were rate-limiting in ethanol metabolism, inhibitors of the enzyme should inhibit the metabolism with the same type of kinetics and the same kinetic constants in vitro and in vivo. Against varied concentrations of ethanol, 4-methylpyrazole is a competitive inhibitor of purified rat liver...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(84)90083-3
更新日期：1984-04-01 00:00:00
abstract：:Preparations of one-chain tissue plasminogen activator (tPA), usually a mixture of 65- and 63-kDa differentially glycosylated forms, contain variable amounts of two-chain tPA. There is no effective procedure currently available for removal of the two-chain contaminant from one-chain tPA preparations. In this report, a...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(91)90375-s
更新日期：1991-03-01 00:00:00
abstract：:Erythropoietin was purified to homogeneity from the culture medium of a baby hamster kidney cell line stably transfected with a human erythropoietin gene. A three-step procedure was used, which included affinity chromatography, ion-exchange chromatography, and reverse-phase chromatography. Purity of the protein was co...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(88)90135-x
更新日期：1988-09-01 00:00:00
abstract：:The intrinsic fluorescence of potato tuber pyrophosphate:fructose-6-phosphate 1-phosphotransferase (PFP) was used as an indicator of conformational changes due to ligand binding. Binding of the substrates and the allosteric activator fructose-2,6-bisphosphate was quantitatively compared to their respective kinetic eff...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/s0003-9861(03)00157-7
更新日期：2003-06-01 00:00:00
abstract：:Dpo4 is a representative model of Y-family DNA polymerase and is therefore one of the most intensively studied DNA polymerase. 6 mA, an epigenetic marker, plays important roles in regulation of various biological processes. However, its effects on DNA replication by Dpo4 is completely unknown. Here, we found that 6 mA...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2019.108120
更新日期：2019-10-30 00:00:00
abstract：:It has been proposed that negatively charged amino acids on the surface of reductase and positively charged amino acids on the surface of P450 mediate the binding of both proteins through electrostatic interactions. In this study, we used a site-directed mutagenesis approach to determine a role for two lysine residues...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.2000.2174
更新日期：2001-01-15 00:00:00
abstract：:Polycation binding to the negatively charged surface of chloroplast thylakoid membranes is known to cause an inhibition of photosystem I activity. It also interferes with the cation-dependent rearrangement of chlorophyll proteins in the thylakoid membrane. It was shown that added anions prevented or reversed the inhib...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(83)90503-9
更新日期：1983-04-01 00:00:00
abstract：:Optimal photosynthetic reaction centre (RC) and core antenna (LH1) levels in the purple bacterium Rhodobacter capsulatus require the puhC gene. Deletion of puhC had little effect on RC and LH1 assembly individually, but significantly inhibited the photosynthetic growth of RC+ LH1- strains, suggesting that maximal RC c...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2006.07.009
更新日期：2006-10-01 00:00:00
abstract：:The vesicle-to-micelle structural transitions that occurred in the interaction of sodium dodecyl sulfate with phosphatidylcholine vesicles were studied at the equilibrium by means of dynamic light scattering (at different scattering angles) and freeze-fracture electron microscopy techniques. The incorporation of surfa...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1999.1267
更新日期：1999-07-15 00:00:00
abstract：:CopA is a protein formed as part of a copper resistance operon in Pseudomonas syringae pv tomato, but CopA has also been identified from gene library screening as a potential lignin-oxidising enzyme. Few bacterial homologues for bacterial multi-copper laccases have been identified that can assist in lignin degradation...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2018.10.012
更新日期：2018-12-15 00:00:00
abstract：:Nitroxides stable radicals are unreactive toward most diamagnetic molecules, but readily undergo one-electron redox reactions with paramagnetic species such as free radicals and transition metals, thus serving as cell-permeable antioxidants. The cytotoxicity of juglone (5-hydroxy-1,4-naphthoquinone), like that of othe...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1994.1323
更新日期：1994-08-01 00:00:00
