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Geny kodující acetyhydroxy syntázu u Streptomyces cinnamonensis a jejich regulační oblast:Mutace v katalytické podjednotce zjią»ující necitlivost k inhibici konečného produktu
Kyselková, Martina ; Kopecký, Jan ; Šigutová, Lucie ; Pospíšil, Stanislav ; Felsberg, Jürgen ; Spížek, Jaroslav ; Janata, Jiří
Reaction of acetohydroxy acid synthase (AHAS) is the key step in branched-chain amino acids biosynthesis. AHAS is feed-back inhibited by valin that binds its regulatory subunit. In Streptomyces cinnamonensis, production of a secondary metabolite, polyether antibiotic monensin A, is associated with valin biosynthesis via 2-oxoisovalerate. Thus, mutants with higher AHAS levels or AHAS insensitive to valin show increased monensin A production. Gene ilvB coding for the AHAS catalytic subunit of the S. cinnamonensis parental strain and four mutants resistant to valin analogues was cloned and sequenced. Nucleotide sequence of ilvB from the strain BVR-18 differed from the wild type in a single substitution C574A resulting in an amino acid change E139A. In the ACB-NLR-2 strain, a triplet AGC in the position 805-807 was deleted resulting in the deletion of Q217. A homology model of the catalytic subunit, created by a virtue of the known three-dimensional structure of the yeast AHAS catalytic subunits dimer, revealed that the mutation found in the BVR-18 was located in a loop at the subunit-subunit interface in a close proximity of the TPP binding site in the active centre. The Q217 deletion in the ACB-NLR-2 occurred in a helix distant from the catalytic site, and seemed to shorten it. AHAS assays in a crude cell extract from the S. cinnamonensis BVR-18 and ACB-NLR-2 strains showed not only the insensitivity to valin but even higher activities of both enzymes in the presence of 10 mM valine. Catalytic and regulatory subunits from the parental and mutant strains were separately expressed in E. coli and combined in vitro to reconstitute the holoenzyme. Properties of such in vitro prepared enzymes were tested. The ACBR-2 and NLR-3 strains with increased AHAS levels have no mutation in the AHAS catalytic subunit. The ilvB regulatory region of those two strains and of the parental strain was cloned and sequenced using the method of chromosome walking. A putative leader peptide and a transcription termination sequence were identified within this region indicating that ilvB expression is controlled by attenuation. However, neither the ACBR-2, nor the NLR-3 have any mutation in the ilvB regulatory region suggesting that some other regulatory mechanism may participate in ilvB expression.
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Analýza genového clusteru anthramycinových a lincosamidových antibiotik
Jelínková, Markéta ; Koběrská, Markéta ; Čermák, Lukáš ; Kopecký, Jan ; Janata, Jiří ; Spížek, Jaroslav
Lincomycin, produced by Streptomyces lincolnensis, is important, clinically used antibiotic. Its gene cluster consists of twenty-seven putative open reading frames with biosynthetic or regulatory functions and three resistance genes. Comparison of the chemical structure of the lincomycin and celesticetin indicates, that in the biosynthesis of celesticetin the whole propylproline branch is absent and proline is substrate of the penultimate step of biosynthesis, the condensation reaction. Second part of biosynthetic pathway including conversion of L-tyrosine to L-proline should be involved in the biosynthesis of functionally different anthramycin antibiotics. Thus it appears, that genetic information on lincomycin and anthramycin biosynthesis must also share common elements (genes), both biosynthetic and regulatory. The organization of transcription units was found. The analysis of the lincomycin biosynthetic gene transcripts in various cultivation stages revealed the genes with putative regulatory functions which are transcribed sooner. A set of probes based on the sequence of lincomycin biosynthetic cluster was used to search for analogous genes in celesticetin producer Streptomyces caelestis and three producers of anthramycin antibiotics: Streptomyces refuineus, Streptomyces albus and Streptosporangium sibiricum. Hybridization experiments proved presence of several analogues of genes coding for sugar moiety biosynthesis in S. caelestis and analogues of some genes coding for anthramycin antibiotics in different anthramycin producers. A rough restriction map of a part of celesticetin gene cluster presumably responsible for sugar moiety biosynthesis shows the gene arrangement to be very similar to that of lincomycin biosynthetic cluster.
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Metodika navrhování řasových fotobioreaktorů: matematické modelování hydrodynamického míchání a předpověď parametrů světelného režimu
Papáček, Š. ; Rálek, P. ; Kopecký, Jiří ; Masojídek, Jiří ; Štys, Dalibor ; Petera, K.
Computational fluid dynamics (CFD) and process simulation are important tools for the design and optimisation of biochemical processes. In this contribution, the photobioreactor design methodology based on CFD is proposed. A widely used CFD package (Fluent 6.1, by Fluent Inc.) performs a numerical approximation of microalgae trajectory (pathline) inside tubular photobioreactor. Consequently, prediction of the level of hydrodynamic mixing and corresponding light regime inside the photobioreactor with effective use of strong light by high-density algal culture is possible. In the first approach, the algal suspension is considered as a single-phase incompressible viscous Newtonian fluid, which fills the whole section of the photobioreactor photic zone. Coupling the cell trajectories with the corresponding light conditions, the light histories of single cells are obtained. These records contain complete information about light regime in photobioreactor. Computer simulations for various photobioreactor design parameters and operating conditions allow to establish the quantitative relation between variables representing design and operating parameters and light regime parameters. Thus the problem of optimal PBR design could be resolved.
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The application of bankruptcy and solvency models on companies in insolvency proceedings
Wenig, Julius ; Kolářová, Blanka (advisor) ; Kopecký, Jiří (referee)
This bachelor thesis elaborates the application of seven bankruptcy and three solvency models on six companies. All of the companies are in insolvency proceedings. The theoretical part concerns with description of the models. The practical part is focused on the results of the models applied on companies and rating information capability of the models. The purpose of the bachelor thesis is to evaluate successfulness of information capability of the models and assess the convenience of their usage.
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System changes in the Czech foreign trade and their influence on its structure
Kopecký, Jan ; Sato, Alexej (advisor) ; Laláková, Eva (referee)
Bachelor thesis consists of six chapters. In the first chapter the essential problems of economic transformation and characteristic features of the Czechoslovak economy are described. Monopoly of the Czechoslovak foreign trade and its abolition at the beginning of the nineties are specified in the second chapter. In the third section author deals with changes in exchange policy and the path towards convertibility. In the fourth and fifth chapters alterations to trade policy containing tariffs, quotas, instruments of trade policy based on conventional basis and state support of export are explained. In the last chapter the influence of transformation on the structure of the Czech foreign trade is graphically depicted and described.
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Energy volatility of the world economy and its impact on energy security of the Czech Republic
Kopecký, Jan ; Bič, Josef (advisor) ; Vondrušková, Barbora (referee)
Sustainable development of the human society is continuously dependent on energy resources. On one side, demand of energy resources still grows while, on the other hand, the availability of energy resources decreases. It is not determined only by decreasing reserves of non-renewable resources but also by other factors - economic, ecologic, technologic and by politics because possession of energy resources helps to strenghten economic power and makes it easier to enforce one's political interests. Thus it is crucial to be concerned with energy volatility of Europe (as a region) since solving this issue in Europe is directly connected with the Czech Republic which cannot deal with its energy volatility in an isolation on a national level.
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Analysis of the web sites of the branch of Informatics, the new design
Kopecký, Jaroslav ; Benáčanová, Helena (advisor) ; Nedomová, Lea (referee)
In the thesis, I deal with the problems of presentation of information provided on the web sites of the Faculty of Informatics and Statistics of The University of Economics, Prague. The work is focused on the appropriate presentation of information from both visual and structural aspects. Furthermore, I deal with the issues of electronic information sources analysis and quality evaluations. I result from a general theory of presentation and I proceed according to the selected analytical points. Emphasis is laid on in terms of briefness, lucidity, clarity and affability for users. The work, in its main articles, is oriented on satisfying the informational needs of students and applicants in their main interests. The aim of the thesis is to analyze the actual state and to improve the quality of the web presentation by providing a variety of proposals.
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Pojišťování úvěrových rizik v mezinárodním podnikání na komerční bázi
Kopecký, Jiří ; Taušer, Josef (advisor) ; Jandera, Tomáš (referee)
Úvěrové riziko je jedním z nejvýznamnějších rizik, kterému jsou mezinárodně činné subjekty při prodeji s odloženou splatností nuceny čelit. Práce popisuje vývoj úvěrového rizika v zemích Evropské unie a v USA a také zmiňuje možné příčiny tohoto vývoje. Dále jsou popsány a porovnány možnosti zajištění úvěrového rizika s důrazem na komerční pojištění pohledávek, které lze v současnosti v zemích střední a východní Evropy považovat za produkt s velkým růstovým potenciálem. V práci jsou identifikovány procesy konsolidace a internacionalizace probíhající na světovém i českém trhu pojištění pohledávek a také vývoj tržních podílů nejvýznamnějších pojišťoven včetně budoucích perspektiv. Na základě případové studie je popsána podstata pojištění pohledávek včetně postupů a pravidel pro likvidaci škody.
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Nosocomial Infections in an In-Patient Department
Kopecký, Jindřich Bc. ; Střítecký, Rudolf (advisor) ; Lešetický, Ondřej (referee)
Nozokomiální infekce jsou v současné době významnou příčinou vzrůstající morbidity a mortality ve všech zdravotnických zařízení. Neznalost či ignorance metod prevence nozokomiálních nákaz může vést k závažnému ohrožení zdraví a života pacienta a výraznému zvýšení nákladů na léčbu. Práce komplexně představuje problematiku nozokomiálních nákaz a jejich efektů na lůžkové zdravotnické zařízení. Pozornost je věnována charakteristice procesu šíření nákaz, popsání současného stavu ve sledování a prevenci nákaz a konečně popsání situace v jedné nemocnici okresního typu.
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Koncept spolupráce podniků a vysokých škol
Kopecký, Jan ; Žid, Norbert (advisor) ; Koucká, Jaroslava (referee)
Diplomová práce se zabývá vztahy mezi podniky a vzdělávacími institucemi týkajících se vzdělávání a budoucího uplatnění studentů na trhu práce. Cílem je navrhnout koncept spolupráce podniků a škol, který by komplexně tyto vztahy pokrýval. Práce definuje předpoklady fungování potřebných procesů v rámci firmy, které jsou ukryty v práci oddělení Human Resources. Na těchto základech práce definuje cíle firem pro spolupráci se školami a navrhuje programy a aktivity, které tuto spolupráci určují. Práce zároveň mapuje předpoklady na straně škol, přínosy a klíčové prvky spolupráce.
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