scholarly journals Optimized heterologous expression of the human zinc enzyme glyoxalase I

1996 ◽  
Vol 314 (2) ◽  
pp. 463-467 ◽  
Author(s):  
Marianne ÖM ◽  
Bengt MANNERVIK
Keyword(s):  
Culture Medium ◽  
Functional Characterization ◽  
Zinc Salt ◽  
Glyoxalase I ◽  
Kinetic Properties ◽  
Coding Region ◽  
Expression Clone ◽  
High Level ◽  
Inhibition Studies

DNA coding for human glyoxalase I was isolated from a HeLa cell cDNA library by means of PCR. The deduced amino acid sequence differs from previously isolated sequences in that a glutamic acid replaces an alanine in position 111. This variant cDNA may represent the more acidic isoform of glyoxalase I originally identified at the protein level. An expression clone was constructed for high-level production of glyoxalase I in Escherichia coli. For optimal yield of the recombinant protein, silent random mutations were introduced in the cDNA coding region. Antisera against human glyoxalase I were used to select a high-level expression clone. This clone afforded 60 mg of purified enzyme per litre of culture medium. Addition of a zinc salt to the culture medium was essential to obtain an active enzyme and a stoicheiometric metal content. The functional characterization of the recombinant enzyme included determination of kinetic constants for methylglyoxal, phenylglyoxal and p-phenylphenylglyoxal, as well as inhibition studies. The kinetic properties of recombinant glyoxalase I were indistinguishable from those of the enzyme purified from human tissues.

scholarly journals What Role Might Non-Mating Receptors Play in Schizophyllum commune?

2021 ◽  
Vol 7 (5) ◽  
pp. 399
Author(s):  
Sophia Wirth ◽  
Daniela Freihorst ◽  
Katrin Krause ◽  
Erika Kothe
Keyword(s):  
Mating Type ◽  
Developmental Stages ◽  
Functional Characterization ◽  
Schizophyllum Commune ◽  
Growth Direction ◽  
Type Locus ◽  
Mating Type Locus ◽  
High Level ◽  
New Evidence

The B mating-type locus of the tetrapolar basidiomycete Schizophyllum commune encodes pheromones and pheromone receptors in multiple allelic specificities. This work adds substantial new evidence into the organization of the B mating-type loci of distantly related S. commune strains showing a high level of synteny in gene order and neighboring genes. Four pheromone receptor-like genes were found in the genome of S. commune with brl1, brl2 and brl3 located at the B mating-type locus, whereas brl4 is located separately. Expression analysis of brl genes in different developmental stages indicates a function in filamentous growth and mating. Based on the extensive sequence analysis and functional characterization of brl-overexpression mutants, a function of Brl1 in mating is proposed, while Brl3, Brl4 and Brl2 (to a lower extent) have a role in vegetative growth, possible determination of growth direction. The brl3 and brl4 overexpression mutants had a dikaryon-like, irregular and feathery phenotype, and they avoided the formation of same-clone colonies on solid medium, which points towards enhanced detection of self-signals. These data are supported by localization of Brl fusion proteins in tips, at septa and in not-yet-fused clamps of a dikaryon, confirming their importance for growth and development in S. commune.

scholarly journals Cloning and characterization of two glutathione S-transferases from a DDT-resistant strain of Anopheles gambiae

1997 ◽  
Vol 324 (1) ◽  
pp. 97-102 ◽  
Author(s):  
Hilary RANSON ◽  
La-aied PRAPANTHADARA ◽  
Janet HEMINGWAY
Keyword(s):  
Anopheles Gambiae ◽  
Resistant Strain ◽  
Sequence Similarity ◽  
Amino Acid Sequences ◽  
Class I ◽  
Kinetic Properties ◽  
Coding Region ◽  
High Sequence Similarity ◽  
Glutathione S Transferases ◽  
High Level

Two cDNA species, aggst1-5 and aggst1-6, comprising the entire coding region of two distinct glutathione S-transferases (GSTs) have been isolated from a 1,1,1-trichloro-2,2-bis-(p-chlorophenyl)ethane (DDT) resistant strain (ZANDS) of Anopheles gambiae. The nucleotide sequences of these cDNA species share 80.2% identity and their derived amino acid sequences are 82.3% similar. They have been classified as insect class I GSTs on the basis of their high sequence similarity to class I GSTs from Drosophila melanogaster and Musca domestica and they are localized to a region of an An. gambiae chromosome known to contain further class I GSTs. The genes aggst1-5 and aggst1-6 were expressed at high levels in Escherichia coli and the recombinant GSTs were purified by affinity chromatography and characterized. Both agGST1-5 and agGST1-6 showed high activity with the substrates 1-chloro-2,4-dinitrobenzene and 1,2-dichloro-4-nitrobenzene but negligible activity with the mammalian theta class substrates, 1,2-epoxy-3-(4-nitrophenoxy)propane and p-nitrophenyl bromide. Despite their high level of sequence identity, agGST1-5 and agGST1-6 displayed different kinetic properties. Both enzymes were able to metabolize DDT and were localized to a subset of GSTs that, from earlier biochemical studies, are known to be involved in insecticide resistance in An. gambiae. This subset of enzymes is one of three in which the DDT metabolism levels are elevated in resistant insects.

Difference of [Ca2+]i Movements in Platelets Stimulated by Thrombin and TRAP: the Involvement of αIIbβ3-Mediated TXA2 Synthesis

1998 ◽  
Vol 79 (06) ◽  
pp. 1184-1190 ◽  
Author(s):  
Yoshiaki Tomiyama ◽  
Shigenori Honda ◽  
Kayoko Senzaki ◽  
Akito Tanaka ◽  
Mitsuru Okubo ◽  
...  
Keyword(s):  
Platelet Aggregation ◽  
Fibrinogen Binding ◽  
Adp Release ◽  
The Difference ◽  
Txa2 Receptor Antagonist ◽  
High Level ◽  
Inhibition Studies ◽  
Peak Increase ◽  
Second Peak ◽  
Assay Conditions

SummaryThis study investigated the difference of [Ca2+]i movement in platelets in response to thrombin and TRAP. The involvement of αIIbβ3 in this signaling was also studied. Stimulation of platelets with thrombin at 0.03 U/ml caused platelet aggregation and a two-peak increase in [Ca2+]i. The second peak of [Ca2+]i, but not the first peak was abolished by the inhibition of platelet aggregation with αIIbβ3 antagonists or by scavenging endogenous ADP with apyrase. A cyclooxygenase inhibitor, aspirin, and a TXA2 receptor antagonist, BM13505, also abolished the second peak of [Ca2+]i but not the first peak, although these regents did not inhibit aggregation. Under the same assay conditions, measurement of TXB2 demonstrated that αIIbβ3 antagonists and aspirin almost completely inhibited the production of TXB2. In contrast to thrombin-stimulation, TRAP caused only a single peak of [Ca2+]i even in the presence of platelet aggregation, and a high level of [Ca2+]i increase was needed for the induction of platelet aggregation. The inhibition of aggregation with αIIbβ3 antagonists had no effect on [Ca2+]i change and TXB2 production induced by TRAP. Inhibition studies using anti-GPIb antibodies suggested that GPIb may be involved in the thrombin response, but not in the TRAP. Our findings suggest that low dose thrombin causes a different [Ca2+]i response and TXA2 producing signal from TRAP. Endogenous ADP release and fibrinogen binding to αIIbβ3 are responsible for the synthesis of TXA2 which results in the induction of the second peak of [Ca2+]i in low thrombin- but not TRAP-stimulated platelets.

Immediate implantation in a patient with chronic generalized parodontitis and apical granuloma

2019 ◽  
Vol 24 (2) ◽  
pp. 145-149
Author(s):  
A. I. Musienko ◽  
K. I. Nesterova
Keyword(s):  
Tooth Extraction ◽  
Tooth Root ◽  
Duration Of Treatment ◽  
Promising Direction ◽  
Aesthetic Result ◽  
Bone Atrophy ◽  
Alveolar Tissue ◽  
High Level ◽  
Immediate Implantation

Relevance. Rehabilitation of patients with moderate to severe generalized periodontitis is a leading problem in periodontology. It was the determination of the prospects for immediate implantation in patients with chronic periodontitis, combined with the pathology of the tooth root and maxillary sinus.Materials and methods. A group of 94 people with periodontitis and chronic odontogenic rhinosinus was observed who underwent sinus surgical treatment, tooth extraction and one-stage implantation with FRP growth factor according to the author's technology.Results. The method showed high efciency on the basis of assessing the clinical, aesthetic result and restoration of bone density after surgery.Conclusions. The developed technology is a promising direction, it allows to combine a high level of sanation of alveolar tissue with the advantages of immediate implantation, prevents bone atrophy, helps reduce the duration of treatment and the number of surgical and orthopedic interventions.

Methodical approaches to managing economic safety of tourism enterprises

2020 ◽  
pp. 160-164
Author(s):  
Leonid Tsubov ◽  
Oresta Shcherban
Keyword(s):  
Safety Management ◽  
Integrated Approach ◽  
Small Enterprise ◽  
Complex Nature ◽  
Efficient Management ◽  
Tourism Enterprises ◽  
High Level ◽  
Functional Components ◽  
Stimulation Control

The set of scientific-methodological tools to secure the mechanism of economic safety management of tourism entrepreneurship is examined as an aggregate of methods, tools, and conceptual activities directed at maintaining the high level of economic safety of tourism entrepreneurship. The features of managing the tourism enterprise and economic safety are analyzed. The basic valuation principles of the reliability and efficiency of the economic safety of the tourism enterprise are determined. The basic tasks of ensuring the economic safety of a small enterprise are outlined. The need to use the integrated approach that secures more opportunities to avoid threats and limits the danger of their emergence is emphasized. The most important principles for securing the economic safety of the tourism enterprise on the microeconomic level are described. Possible practical methods of risk management for the implementation of adopted decisions are proposed. The paper proves the fact that the complex nature of the management of the economic safety of the tourism enterprise and securing the sufficiently efficient management system of detecting and eliminating the threats are provided by the establishment of the management of the economic safety system of the tourism enterprise and its functional components. Research of the methodical approaches to the management of the tourism enterprises’ economic safety allows building and describing the functional structure of the mechanism of management of the tourist enterprise’s economic safety (it is formalized and described by 5 functions: determination of aims; planning; organization and adjusting; motivation and stimulation; control and monitoring).

scholarly journals Study of Well Waters from High-Level Natural Radiation Areas in Northern Vietnam

2021 ◽  
Vol 18 (2) ◽  
pp. 469
Author(s):  
Van-Hao Duong ◽  
Thanh-Duong Nguyen ◽  
Miklos Hegedus ◽  
Erika Kocsis ◽  
Tibor Kovacs
Keyword(s):  
Natural Radionuclide ◽  
World Health ◽  
Natural Radiation ◽  
Lifetime Cancer Risk ◽  
Northern Vietnam ◽  
Health Organization ◽  
High Level ◽  
Radiological Hazard Indices ◽  
Well Waters

The determination of natural radionuclide concentrations plays an important role for assuring public health and in the estimation of the radiological hazards. This is especially true for high level radiation areas. In this study, 226Ra, 228Ra and 238U concentrations were measured in well waters surrounding eight of the high-level natural radiation areas in northern Vietnam. The 226Ra, 228Ra and 238U activity concentrations vary from <1.2 × 10−3–2.7 (0.46), <2.6 × 10−3–0.43 (0.07) and <38 × 10−3–5.32 Bq/L (0.50 of median), respectively. 226Ra and 238U isotopes in most areas are in equilibrium, except for the DT-Thai Nguyen area. The calculated radiological hazard indices are generally higher than WHO (World Health Organization) recommendations. Average annual effective dose and excess lifetime cancer risk values due to drinking well water range from to 130 to 540 μSv/year and 7.4 × 10−6 to 3.1 × 10−5, respectively.

Colorimetric Determination of Aklomide (2-Chloro-4-Nitrobenzamide) in Poultry Feed

1969 ◽  
Vol 52 (3) ◽  
pp. 438-441
Author(s):  
Glenn M George ◽  
A C Daftsios ◽  
Joseph L Morrison
Keyword(s):  
Nitro Group ◽  
Poultry Feed ◽  
Colorimetric Determination ◽  
Average Recovery ◽  
Low Level ◽  
Color Development ◽  
Titanium Trichloride ◽  
High Level

Abstract The coccidiostat aklomide is extracted from feed with methanol and assayed colorimetrically by reduction of the nitro group to anamine with titanium trichloride and subsequent color development with t he Bratton-Marshall reaction. Thirteen laboratories studied the method collaboratively on two levels of medicated feed. Overall average recovery was 106.5% of the oretical for the low level and 104.5% of the oretical for the high level. The method is recommended for adoption as official first action

scholarly journals Revealing the constituents of Egypt’s oldest beer using infrared and mass spectrometry

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Mohamed A. Farag ◽  
Moamen M. Elmassry ◽  
Masahiro Baba ◽  
Renée Friedman
Keyword(s):  
Large Scale ◽  
Beer Brewing ◽  
Chemical Signatures ◽  
Chemical Determination ◽  
Materials Used ◽  
High Level ◽  
Beer Production ◽  
First Time ◽  
Detailed Chemical

Abstract Previous studies have shown that the Ancient Egyptians used malted wheat and barley as the main ingredients in beer brewing, but the chemical determination of the exact recipe is still lacking. To investigate the constituents of ancient beer, we conducted a detailed IR and GC-MS based metabolite analyses targeting volatile and non-volatile metabolites on the residues recovered from the interior of vats in what is currently the world’s oldest (c. 3600 BCE) installation for large-scale beer production located at the major pre-pharaonic political center at Hierakonpolis, Egypt. In addition to distinguishing the chemical signatures of various flavoring agents, such as dates, a significant result of our analysis is the finding, for the first time, of phosphoric acid in high level probably used as a preservative much like in modern beverages. This suggests that the early brewers had acquired the knowledge needed to efficiently produce and preserve large quantities of beer. This study provides the most detailed chemical profile of an ancient beer using modern spectrometric techniques and providing evidence for the likely starting materials used in beer brewing.

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