Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Formyltetrahydrofolate synthetase from Clostridium thermoaceticum has been crystallized using the hanging-drop method from ammonium sulphate and PEG solutions. Crystals are trigonal, the space group is R32, a = 163 A, c = 259 A. A 4.2 A resolution data set has been collected. Analysis of the data using the self-rotation function shows that tetramers have approximate 222 symmetry and are positioned on a crystallographic 2-fold axis.
J Mol Biol 1993 Feb 20
PMID:Crystallization and preliminary crystallographic data for formyltetrahydrofolate synthetase from Clostridium thermoaceticum. 844 41

We have used the bar gene in combination with the herbicide Basta to select transformed rice (Oryza sativa L. cv. Radon) protoplasts for the production of herbicide-resistant rice plants. Protoplasts, obtained from regenerable suspension cultures established from immature embryo callus, were transformed using PEG-mediated DNA uptake. Transformed calli could be selected 2-4 weeks after placing the protoplast-derived calli on medium containing the selective agent, phosphinothricin (PPT), the active component of Basta. Calli resistant to PPT were capable of regenerating plants. Phosphinothricin acetyltransferase (PAT) assays confirmed the expression of the bar gene in plants obtained from PPT-resistant calli. The only exceptions were two plants obtained from the same callus that had multiple copies of the bar gene integrated into their genomes. The transgenic status of the plants was verified by Southern blot analysis. In our system, where the transformation was done via the protoplast method, there were very few escapes. The efficiency of co-transformation with a reporter gene gusA, was 30%. The T0 plants of Radon were self-fertile. Both the bar and gusA genes were transmitted to progeny as confirmed by Southern analysis. Both genes were expressed in T1 and T2 progenies. Enzyme analyses on T1 progeny plants also showed a gene dose response reflecting their homozygous and heterozygous status. The leaves of T0 plants and that of the progeny having the bar gene were resistant to application of Basta. Thus, the bar gene has proven to be a useful selectable and screenable marker for the transformation of rice plants and for the production of herbicide-resistant plants.
Plant Mol Biol 1993 Mar
PMID:Use of bar as a selectable marker gene and for the production of herbicide-resistant rice plants from protoplasts. 846 80

The structure-function study of hydroxysteoid dehydrogenases has stimulated the development of their chromatography, which in turn reveals more mechanisms of these enzymes. Due to the various membrane associations and mild hydrophobic nature of most of the enzymes studied up to now, hydrophobic interaction chromatography has played a crucial role in their purification, using media such as phenyl-Superose or Sepharose-PEG. At the same time, affinity chromatography, especially the dye-containing columns, proves very efficient for these dehydrogenases, as the latter utilizes adenylyl-containing cofactors. Elution by their specific ligand facilitates their purification. In this paper, the use of detergents in the purification of these enzymes is also reviewed. Hydroxysteroid dehydrogenase preparation is further improved by rapid purification which facilitates the elimination of protein microheterogeneity, caused in vitro by oxidation, reduction or partial proteolysis. This process was shown to increase the crystallizability of the enzymes [Lin et al., J. Cryst. Growth, 122 (1992) 242-245; Zhu et al., J. Mol. Biol., 234 (1993) 242-244]. The fast purification permitted a simpler procedure and better combination of various columns than conventional chromatography. This leads to even higher efficiency, yielding homogeneous and highly active preparations.
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PMID:Chromatography of hydroxysteroid dehydrogenases. 890 68

A gene which codes for a thermostable endo beta-1,3-glucanase (EC 3.2.1.39) from a Gram positive anaerobic thermophilic bacteria Clostridium thermocellum F7, was fused to 35S promoter and polyadenylation signal of Cauliflower Mosaic Virus (CaMV) strain Cabb B-D. This chimaeric gene fusion was introduced into Nicotiana plumbaguinifolia protoplasts using PEG-mediated DNA transfer method of transformation. Transient expression of the thermostable endo beta-1,3-glucanase was carried out in the protoplasts and was assayed at 70 degrees C pH 8.0, suggesting that the chimaeric gene fusion: (i) is correctly transcribed and translated in plant cells; (ii) the product of translation (the thermostable endo beta-1,3-glucanase protein) is easy to assay since most of the plants' enzymes have their optimal reaction temperature at 40-60 degrees C and at neutral or weak-acidic condition which is a characteristic of plant cells; (iii) can be used as a model for studying and understanding some of the mechanisms of plant defence systems at the enzyme protein level, in case of stress conditions.
Mol Gen Mikrobiol Virusol 1997
PMID:Expression of a bacterial endo beta-1,3-glucanase gene under the control of CAMV 35S promoter in Nicotiana plumbaguinifolia protoplasts. 904 96

Solid-phase organic synthesis is now a prevalent activity in drug discovery. In keeping with this keen interest is the need to develop reliable automated synthesis instrumentation as well as polymeric supports and linkers suitable for the full range of organic synthesis applications. In this paper, we review our activities in the development of new and enabling tools for automated chemical synthesis, including the following: (i) new solid supports such as ArgoGel (PS-PEG-based) and Argo-X203 (PS-based); and (ii) the Nautilus 2400 system, a fully closed and inert automated chemistry development workstation. Selected chemistry optimization and synthesis examples performed on the Nautilus and new solid supports will be described.
Mol Divers 1997
PMID:Automated chemical synthesis: from resins to instruments. 924 55

We investigated the effect of hemorrhagic shock and reinfusion on the cardiac function and contractility, plasma CK and CK-MB activity and lactate concentration, oxyradical-producing activity of polymorphonuclear leukocytes (PMNL-CL), cardiac chemiluminescence (LV-CL), antioxidant enzyme activity [superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-PX)] and malondialdehyde (MDA) concentration in anesthetized dogs to determine the role of oxyradicals in cardiac depression and cellular injury in hemorrhagic shock and reinfusion. The dogs were assigned into three groups: I (sham), 4 h duration; II (S + R), 2 h of shock followed by reinfusion for 2 h; III (SOD + S + R), as II but pretreated with PEG-SOD. Hemorrhagic shock was produced by withdrawal of blood to maintain the mean arterial pressure at 50 +/- 5 mm Hg. Cardiac function and contractility were depressed during hemorrhagic shock. Plasma CK, CK-MB and lactate increased during shock. Following reinfusion after 2 h of shock hemodynamic parameters and plasma lactate tended to return towards control values. Plasma CK and CK-MB, PMNL-CL and cardiac MDA, total-, Mn- and CuZn-SOD activity increased while LV-CL decreased. In spite of the increase in the antioxidant reserve, there was oxidative damage. Pretreatment with SOD attenuated the deleterious effects of shock and reinfusion on the cardiovascular function, plasma CK, and CK-MB, PMNL-CL, cardiac MDA, SOD, and LV-CL. Protection was incomplete for cardiovascular function and plasma CK and CK-MB. These results suggest that oxyradicals may partly be involved in the deterioration of cardiovascular function and cellular injury during hemorrhagic shock and reinfusion.
Mol Cell Biochem 1997 Nov
PMID:Cardiac depression and cellular injury in hemorrhagic shock and reinfusion: role of free radicals. 940 75

The relationship of imposed water activity a(w) (equilibrium relative humidity) with conventional water status parameters and proton spin-lattice relaxation time T1 of leaf water was studied in pearl millet and wheat. The water activities of different levels were created by equilibrating the leaves in varying concentrations of PEG-6000 solutions. With decreasing a(w), relative water content and T1 decreased linearly and other variables (leaf water potential and leaf water content) decreased exponentially upto a dehydration level of a(w) approximately 0.978 for pearl millet, 0.986 for drought susceptible wheat var. HD2329 and 0.975 for tolerant wheat var. C306. Below that level there was abrupt reduction in all parameters except T1 which registered an increase. The changes in short and long components of T1 with changes in a(w) have also have been discussed for pearl millet.
Cell Mol Biol (Noisy-le-grand) 1997 Dec
PMID:Relationship between NMR relaxation characteristics and water activity in cereal leaves. 948 44

Knowledge of bovine oocyte plasma membrane permeability characteristics at different developmental stages in the presence of cryoprotective agents (CPAs) is limited. The objective of this study was to determine the oolema hydraulic conductivity (Lp), cryoprotectant permeability (P[CPA]), and reflection coefficient (sigma) for immature (germinal vesicle stage, GV) and in vitro-matured (metaphase II, MII) bovine oocytes. Two commonly used cryoprotective agents, dimethyl sulfoxide (DMSO) and ethylene glycol (EG), were studied. Osmometric studies were performed using a micromanipulator connected to an inverted microscope at 22 +/- 2 degrees C. Each oocyte was immobilized via a holding pipette, and osmotically induced volume changes over time (dv/dt) were recorded. The Lp values for GV and MII oocytes in DMSO (L(p)DMSO) were 0.70 +/- 0.06 and 1.14 +/- 0.07 microm/min/atm (mean +/- SEM) and in EG (L(p)EG) were 0.50 +/- 0.06 and 0.83 +/- 0.07 microm/min/atm, respectively. Estimates of P(DMSO) for GV and MII oocytes were 0.36 +/- 0.03 and 0.48 +/- 0.03 microm/sec, and PEG values for GV and MII oocytes were 0.22 +/- 0.03, 0.37 +/- 0.03 microm/sec, respectively. The values for GV and MII oocytes in DMSO (sigma[DMSO]) were 0.86 +/- 0.03 and 0.90 +/- 0.04 and in EG (sigma[EG]) were 0.94 +/- 0.03 and 0.76 +/- 0.04, respectively. These data demonstrate that bovine oolema permeability coefficients to water and cryoprotectants change after in vitro maturation. Furthermore, the bovine oocyte P(DMSO) is higher than the P(EG). These results may provide a biophysical basis for developing criteria for choosing optimal CPAs and for minimizing damage during addition and removal of the CPAs. Additionally, these data support the hypothesis that different procedures may be required for optimal cryopreservation of different oocyte developmental stages.
Mol Reprod Dev 1998 Apr
PMID:Effect of developmental stage on bovine oocyte plasma membrane water and cryoprotectant permeability characteristics. 950 92

The glycolytic enzyme phosphoglycerate kinase (PGK) catalyzes phosphoryl transfer between 1,3-bis-phosphoglycerate and ADP to form 3-phosphoglycerate and ATP. During catalysis, a major hinge bending motion occurs which brings the N and C-terminal enzyme domains and their bound substrates together and in-line for phosphoryl transfer. We have crystallized Trypanosoma brucei PGK in the presence of the bisubstrate analog, adenylyl 1,1,5,5-tetrafluoropentane-1, 5-bisphosphonate, and solved the structure of this complex in two different crystal forms at 1.6 and 2.0 A resolution, obtained from PEG 8000 and ammonium phosphate solutions, respectively. These high resolution structures of PGK:inhibitor complexes are of particular interest for drug design since Trypanosoma brucei, the causative agent of African sleeping sickness, relies on glycolysis as its sole energy source. In both structures, the inhibitor is bound in a fully extended conformation with its adenosine moiety assuming exactly the same position as in ADP:PGK complexes and with its 5' phosphonate group occupying part of the 1,3-bis-phosphoglycerate binding site. The bisubstrate analog forces PGK to assume a novel, "inhibited" conformation, intermediate in hinge angle between the native structures of open and closed form PGK. These structures of enzyme-inhibitor complexes demonstrate that PGK has two distinct hinge points that can each be independently activated. In the "PEG" structure, the C-terminal hinge is partially activated while the N-terminal hinge point remains in an open state. In the "phosphate" structure, closure of the N-terminal hinge point is also evident. Finally and most unexpectedly, both complex structures also contain a 3 A shift of a helix that lies outside the flexible hinge region. We propose that a transient shift of this helix is a required element of PGK hinge closure during catalysis.
J Mol Biol 1998 Jun 26
PMID:A bisubstrate analog induces unexpected conformational changes in phosphoglycerate kinase from Trypanosoma brucei. 964 90

Crystallographic studies of ribosomal proteins from bacteria progressed rapidly during the last decade, though the structures of ribosomal proteins from other kingdoms have not yet been published. Here we describe crystals of archaeal ribosomal protein L1 from Methanococcus jannaschii. The protein crystals were grown in 10% PEG 10 K, 50 mM Hepes-HCl (pH 7.5) in hanging drops equilibrated against 33% PEG 10 K, 100 mM Hepes-HCl (pH 7.5). The crystals diffract to at least 2.5 A resolution and belong to the space group P1 with cell parameters a = 34.09 A, b = 39.39 A, c = 55.84 A, alpha = 83.65 degrees, beta = 80.38 degrees, gamma = 75.37 degrees.
Biochem Mol Biol Int 1998 Jun
PMID:Crystals of ribosomal protein L1 from a hyperthermophilic archaeon Methanococcus jannaschii. 967 56


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