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1
Content available remote Synthetic biology in perspective
EN
Towards the end of the XXth century, genetics expanded its scope not only in the field of structure and mechanisms of heredity, owing to progress in nucleic acid research including efficient sequencing and reassembly methods, but in acquiring precise tools which enable construction of new forms of life. Synthetic biology marks a radical change in practices of genetic manipulation from random mutations followed by selection, to design of specific DNA transformations attainable by application of genetic engineering methods. Mastering enzymatic gene splicing procedures and chemical synthesis of polynucleotides allowed perceiving macromolecules of life as “parts” or “bricks” amenable to specification, cataloguing and also fit for applications commensurable with the rules of engineering. The purpose of synthetic biology is to apply defined macromolecular constructs (abstracted from living matter or synthetic) as modules for construction of devices, sensors or switches, which can ultimately be integrated into self-sustained systems. Target applications of synthetic biology products ranges from biotechnological manufacturing of energy, fuels, chemicals, food and pharmaceuticals, through marker sensors and diagnostic devices, to various classes of therapeutics like antibodies, vaccines, probiotic microbes or modified immune cells. Thus, synthetic biology becomes an integral part of the prospective switch from present industrial reality to circular bioeconomy, which is the greatest challenge facing humanity.
PL
Na przełomie stuleci genetyka zyskała, w wyniku dogłębnych badań nad kwasami nukleinowymi, nowe specyficzne narzędzia modyfikacji materiału genetycznego, nieporównywalnie skuteczniejsze od wykorzystywanych uprzednio przypadkowych mutacji z następczą selekcją. W wyniku rozwoju różnych form biotechnologii, korzystających z narzędzi inżynierii genetycznej wyłoniła się (najpierw w formie postulatywnej) biologia syntetyczna, zakładając wykorzystanie funkcjonalnych biomakromolekuł jako elementów zamiennych (cegiełek lub podzespołów) do projektowania i konstrukcji większych modułów, systemów a wreszcie organizmów, spełniających z góry zadane założenia metaboliczne. Zadaniem biologii syntetycznej jest zapewnienie dostępności (docelowo w skali procesów przemysłowych) układów biologicznych zdolnych do korzystnego przetwarzania energii (szczególnie solarnej), transformacji składników biomasy w niskoemisyjne paliwa, półprodukty chemiczne, biopolimery oraz składniki żywności i leków. Inne zastosowania biologii syntetycznej koncentrują się w obszarze ochrony zdrowia; projektowane obecnie konstrukty będą spełniać role markerów i sensorów dla diagnostyki, probiotyków dla profilaktyki oraz przeciwciał, szczepionek a nawet celowo reprogramowanych komórek (np. układu immunologicznego) dla terapii lub medycyny rekonstrukcyjnej.
2
Content available remote Jak najefektywniej oczyszczać ścieki przemysłowe z nadtlenku wodoru?
PL
Przeprowadzono analizę matematyczną by ocenić, czy zastosowanie optymalnego sterowania temperaturą w procesie rozkładu nadtlenku wodoru przez natywną katalazę Terminox Ultra jest uzasadnione. Oceny dokonano w oparciu o wskaźnik będący ilorazem czasów trwania procesu prowadzonego przy optymalnym profilu temperatury oraz w warunkach izotermicznych. Wykazano, że zastosowanie optymalnego sterowania temperaturą jest uzasadnione, gdy proces przebiega do osiągnięcia wysokich stopni przemiany oraz niskich aktywności enzymu. Dodatkowo wprowadzenie ograniczeń temperaturowych obniża wartość ocienianego wskaźnika. Przedstawiona analiza może być pomocna przy ekonomicznej ocenie procesów sterowanych optymalnie.
EN
A mathematical analysis is proposed to assess if the application of optimal temperature control (OTC) in the hydrogen peroxide decomposition process by Terminox Ultra catalase is justified. The estimation was performed on basis of the indicator expressed by a quotient of process duration under time-optimal temperature control and that for isothermal conditions (IC). It was found that the application of OTC is justified when the process under consideration is running up to attain a high conversion and low final enzyme activity. Additionally, the application of temperature constraints causes a decrease of the assessed indicator value. The framework proposed here can be helpful for the evaluation of economic aspects of optimally controlled processes.
EN
Considerable progress has been made in the past few years with industrial use of essential key intermediates for chemical and pharmaceutical industry. The increasing demand for obtaining chiral drugs in enantiomerically pure form makes it necessary to search for novel biocatalysts useful in the synthesis of amino acids, chiral amines, amino sugars and alcohols. According to the reaction mechanism, aminotransferases (ATs) have useful applications because of their capability of transfer of an amino group from a donor substrate to an acceptor, thus resulting in the synthesis of a wide variety of building blocks. This article reviews current biocatalytic approaches using microbial ATs in the synthesis of optically active products. Focus is also put on the engineering of ATs and their limitations in the industrial applications. Moreover this review covers biocatalytic approaches using ATs isolated from extreme environments.
EN
Biotransformations involve mainly microorganisms or individual enzymes applied to catalyze chemical reactions [1]. This field of science is particularly important, because it allows to obtain optically active compounds, which are valuable raw materials for pharmaceutical (Fig. 3, Fig. 6, Fig. 20, Fig. 21), wood and paper (Fig. 18), food (Fig. 4), textile (Fig. 12), cosmetic (Fig. 14) industries and environmental protection (Fig. 19). Oxidoreductases, in particular alcohol dehydrogenases (E.C.1.1.1.1, ADH) are valuable biocatalysts enabling to obtain enantiomerically pure products. These enzymes, commonly found in nature, catalyze both oxidation and reduction reactions [3]. Described dehydrogenases descend from mesophilic, psychrophilic and thermophilic microorganisms. The increasing application of thermophiles is due to their exceptional resistance against heat and organic solvents. The article describes and explains how microbial ADH’s interact with NAD+/NADH or NADP+/NADPH and present those enzymes which catalyze reactions with both forms of cofactors. The alcohol dehydrogenases from yeast are particularly commonly used [9–14]. Bacterial enzymes, among them ADH isolated from Thermoanaerobacter brockii [47–51], are widely distributed too. In addition, the literature describes a number of (R)-specific ADH’s from Lactobacillus kefir [40–42], L. brevis [45, 46], Leisofonia sp. [20] Pseudomonas fluorescens [23] and (S)- -specific ADH’s from Rhodococcus erythropolis [15, 16], Thermus sp. [30], Sulfolobus solfataricus [23, 28] and many others.
PL
Celem badań był rozdział kinetyczny mieszaniny racemicznej kwasu 2-butyryloksy-2-(etoksy-P-fenylofosfinylo)octowego na drodze biotransformacji z wykorzystaniem biokatalizatora całokomórkowego. Optycznie czyste produkty mogą znaleźć zastosowanie jako dyskryminatory chiralności oraz bloki budulcowe do syntezy związków biologicznie czynnych, takich jak leki czy środki ochrony roślin. Biokatalizatorem użytym w przeprowadzonej syntezie był szczep Penicillium oxalicum o potwierdzonych właściwościach lipolitycznych. Zbadano również wpływ dodatku oleju roślinnego na indukcję syntezy lipaz przez grzyby oraz na efektywność procesu biotransformacji. Zastosowanie induktora nie wpłynęło pozytywnie na szybkość procesu, zaobserwowano natomiast znaczące różnice w enancjoselektywności reakcji.
EN
The aim of the study was to resolve the racemic mixture of 2-butyryloxy-2-(ethoxy-P-phenylphosphinyl)acetic acid by kinetically controlled biotransformation with whole-cell biocatalyst – Penicillium oxalicum strain with confirmed lipolytic activity. Also effect of the vegetable oil addition on induction of fungal lipases synthesis and efficiency of the biotransformation process was examined. The use of inductors did not positively influenced the degree of substrate conversion, while significant differences were observed in the enantioselectivity of the reaction.
EN
Baker’s yeast Saccharomyces cerevisiae is quite commonly applied as a wholecell biocatalysts in biotransformations – reactions based on enzymatic transformations of chemical compounds. Yeast cells are easy in cultivation and use. They are usually used to catalyze such reactions as bioreduction or hydrolysis. The full sequencing of its genome accompanied with achievements of genetic engineering allowed to design new yeast strains characterized by high conversion yield and reaction selectivity. Genetically modified cells of Saccharomyces cerevisiae catalyze biotransformations, which lead to chiral building blocks important in pharmaceutical industry (especially those obtained by reduction of á- and â -oxoesters). „Designer yeast” is a new catalyst for Baeyer–Villiger oxidation. Recombinant yeast lipases have been discussed as useful means in biodiesel production because the microbiological method of producing of this kind of fuel has many advantages. There is a growing interest in application of modified yeast in biotransformation reactions. Modern directions to improve catalytic abilities of baker’s yeast include: the use of surface display technology of enzymes, optimization or increase in availability of cofactor required for bioreduction reactions or gene knock-out, which eliminates the activity of enzymes with conflicting and unwanted stereoselectivities. Commonly used technique is also overexpression of the desired protein or expression of heterologous enzymes in yeast cells.
8
Content available remote Perspektywy rozwoju biotechnologii przemysłowej w Unii Europejskiej
EN
White, or industrial, biotechnology is the application of biotechnology for the processing and production of chemicals, materials, and energy. White biotechnology uses enzymes and microorganisms to generate products in industrial sectors as diverse as pharmaceuticals and chemistry, food and feed, pulp and paper, textiles or detergents. This review gives an overview of the possible developments in the transition to bio-based production with a focus on the production of chemicals. Implementation of industrial biotechnology offers significant ecological advantages. Renewable agricultural crops are the preferential starting materials, instead of dwindling fossil resources such as crude oil and natural gas. This technology consequently has a beneficial effect on greenhouse gas emissions and at the same time supports the agricultural sector, delivering these raw materials. Moreover, industrial biotechnology frequently shows significant performance benefits compared to conventional chemical technology, such as a higher reaction rate, increased conversion efficiency, improved product purity, lowered energy consumption and significant decrease in chemical waste generation. The combination of these factors has led to the recent strong penetration of industrial biotechnology in all sectors of the chemical industry, particularly in fine chemicals but equally so for bulk chemicals such as plastics and fuels. The chemical industry in Europe, which contributes about 28% of the world demand for chemicals, has identified industrial biotechnology as a key emerging technology area. The biorefinery concept offers numerous possibilities to integrate the production of bio-energy and chemicals. This will also provide substantially higher value-added economic activities, besides promoting production in agriculture and forestry. Shifting the resource base for chemical production from fossil feedstocks to renewable raw materials provides exciting possibilities for the use of industrial biotechnology-based process tools. In a bio-based production, industrial biotechnology also interfaces with plant biotechnology (green biotechnology), where gene technology is applied to accelerate the process of plant breeding for crop improvement or for altering the composition of the feedstock for a desired product. The concept of Knowledge-Based Bio-Economy and the vision of bio-economy in Europe to 2030 presented in so called "Cologne Paper". [82] are also briefly outlined.
9
Content available remote Zastosowanie biotransformacji w syntezie optycznie czynnych laktonów
EN
Compounds with lactone moiety exhibit many biological acitivities (for example antimicrobial, antifeedant, cytostatic). One of the most attractive methods to obtain optically active lactones are regio- and stereoselective biotransformations. These together with mild reaction conditions are the main advantages of the processes compared to chemical synthesis of lactones. In this review examples of such biotransformations are presented. The lactones may be obtained via direct biotransformation of substrate or in chemoenzymatic synthesis. In the second case the enzymatic step is the key one, leading to optically pure or enriched intermediate which is further transformed into desired, optically active product. As the products of direct biotransformation, lactones can be formed from fatty acids like ricinoleic or vernolic acid [1, 2], aromatic compounds (benzoic acid, mandelic acid, catechol) [3] as well as in the result of lactonization of epoxyesters by enzymatic systems of fungi or plants. In the last case the biocalysts is the apple pulp or Jerusalem artichoke pulp [4-6]. Hydrolysis of amides and nitriles is also applied to the synthesis of lactones. Especially useful in this regard are microorganisms, which exhibit both enzymatic activities [7-9]. Microbial reduction of carbonyl group in ketoesters or ketoacids is also very useful method. The reduction may occur in ? or ? position, leading to ?- or ?-hydroxyacids which cyclize to the corresponding lactones [10-13]. Reduction of carbonyl group in ?-position is the first step of a synthesis of lactones with 7- or 8-membered rings [14-16]. The application of hydrolysis or transesterification processes catalyzed by hydrolytic enzymes, mainly lipases from Pseudomonas sp., also leads to enzymatically enriched lactones. The substrates may be ?-ketoesters, ?-hydroxyamides, meso-diols or meso-diesters [10, 17-19]. Among the oxidation reaction the most known is Baeyer-Villiger reaction in which cyclic ketones are directly oxidized to the lactones by enzymes called Baeyer-Villiger monooxygenases (BVMO) [20]. The reaction is highly regioselective and can be applied to the production of unsaturated lactones [23]. In this area of research genetically modified strains of Escherichia coli are applied [21, 24], although the wild strains are also used, for example to the production of ?-caprolactone from cyclohexanone [22]. Another reaction catalyzed by oxidoreductases is the oxidation of hydroxyl group to carbonyl or carboxyl one [25-27]. In this first case horse liver alcohol dehydrogenase (HLADH) found application in the oxidation of meso-diols to lactones. The ability of different fungal strains to the regioselective hydroxylation of unactivated carbon atom found an application to the synthesis of lactones with eudesmane and germacrane systems [28-30]. Resolution of racemates is an alternative strategy used to the synthesis of lactones in optically pure forms. This aim can be achieved by enzymatic cleavage of lactone ring catalyzed by lactonases. These enzymes of microbial origin belong to esterases and are often induced during the growth of microorganisms on cyclic ketones as the carbon sources [31, 32, 34]. Enzymatic resolution of pantolactone by lactonase from Fusarium oxysporum is an example of industrial biotransformation [33]. Lipases can also be applied to the enantioselective hydrolysis of lactone ring [35-37]. The other functional groups present in the molecule can also be converted during the resolution of racemic lactones [39-44]. The examples are hydrolysis of acetoxylactones or esterification of hydroxylactones.
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