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Thioredoxin and Glutaredoxin Systems

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ISBN: 9783038978367 / 9783038978374 Year: Pages: 280 DOI: 10.3390/books978-3-03897-837-4 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Science (General) --- Biology
Added to DOAB on : 2019-06-26 08:44:06
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Abstract

This Special Issue features recent data concerning thioredoxins and glutaredoxins from various biological systems, including bacteria, mammals, and plants. Four of the sixteen articles are review papers that deal with the regulation of development of the effect of hydrogen peroxide and the interactions between oxidants and reductants, the description of methionine sulfoxide reductases, detoxification enzymes that require thioredoxin or glutaredoxin, and the response of plants to cold stress, respectively. This is followed by eleven research articles that focus on a reductant of thioredoxin in bacteria, a thioredoxin reductase, and a variety of plant and bacterial thioredoxins, including the m, f, o, and h isoforms and their targets. Various parameters are studied, including genetic, structural, and physiological properties of these systems. The redox regulation of monodehydroascorbate reductase, aminolevulinic acid dehydratase, and cytosolic isocitrate dehydrogenase could have very important consequences in plant metabolism. Also, the properties of the mitochondrial o-type thioredoxins and their unexpected capacity to bind iron–sulfur center (ISC) structures open new developments concerning the redox mitochondrial function and possibly ISC assembly in mitochondria. The final paper discusses interesting biotechnological applications of thioredoxin for breadmaking.

Keywords

methionine --- methionine sulfoxide --- methionine sulfoxide reductase --- physiological function --- protein --- plant --- repair --- redox homeostasis --- signaling --- stress --- mitochondria --- thioredoxin --- iron–sulfur cluster --- redox regulation --- ALAD --- tetrapyrrole biosynthesis --- redox control --- thioredoxins --- posttranslational modification --- chlorophyll --- redox regulation --- thioredoxin --- ferredoxin-thioredoxin reductase --- chloroplast --- H2O2 --- redox signalling --- development --- regeneration --- adult stem cells --- metazoan --- cyanobacteria --- thioredoxin --- photosynthesis --- redox active site --- thioredoxin --- disulfide --- flavin --- NADPH --- X-ray crystallography --- SAXS --- methanoarchaea --- chilling stress --- cold temperature --- posttranslational modification --- regulation --- ROS --- thiol redox network --- thioredoxin --- thioredoxin --- Calvin-Benson cycle --- photosynthesis --- carbon fixation --- chloroplast --- macromolecular crystallography --- protein-protein recognition --- electrostatic surface --- Chlamydomonas reinhardtii --- thioredoxin --- glutaredoxin --- legume plant --- symbiosis --- redox homeostasis --- stress --- thioredoxin --- monodehydroascorbate reductase --- water stress --- protein oxidation --- antioxidants --- ascorbate --- glutathione --- wheat --- thioredoxin --- thioredoxin reductase --- baking --- redox --- dough rheology --- protein oxidation --- methionine oxidation --- methionine sulfoxide reductases --- oxidized protein repair --- ageing --- Chlamydomonas reinhardtii --- cysteine alkylation --- cysteine reactivity --- MALDI-TOF mass spectrometry --- thioredoxin --- X-ray crystallography --- Isocitrate dehydrogenase --- glutathionylation --- nitrosylation --- glutaredoxin --- Arabidopsis thaliana --- thioredoxins --- plastidial --- specificity --- function --- proteomic --- photosynthesis --- Calvin cycle --- n/a

Biological and Biogenic Crystallization

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ISBN: 9783038975212 Year: Pages: 106 DOI: 10.3390/books978-3-03897-522-9 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Science (General) --- Biology
Added to DOAB on : 2019-03-08 11:42:05
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The intention of the Special Issue ""Biological and Biogenic Crystallization"" was to create an international platform aimed at covering a broad field of results involving the crystallization of biological molecules, including virus and protein crystallization, biogenic crystallization including physiological and pathological crystallization taking place in living organisms (human beings, animals, plants, bacteria, etc.), and bio-inspired crystallization. Despite many years of research on biological and biogenic crystals, there are still open questions as well as hot and timely topics. This Special Issue contains seven articles that present a cross-section of the current research activities in the of field of biological and biogenic crystals. The authors of the presented articles prove the vibrant and topical nature of this field. We hope that this Special Issue will serve as a source of inspiration for future investigations, and will be useful for scientists and researchers who work on the exploration of biological and biogenic crystals.

Asymmetric and Selective Biocatalysis

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ISBN: 9783038978466 9783038978473 Year: Pages: 154 DOI: 10.3390/books978-3-03897-847-3 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Science (General) --- Chemistry (General)
Added to DOAB on : 2019-06-26 09:16:44
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This Issue contains one communication, six articles, and two reviews. The communication from Paola Vitale et al. represents a work where whole cells were used as biocatalysts for the reduction of optically active chloroalkyl arylketones followed by a chemical cyclization to give the desired heterocycles. Among the various whole cells screened (baker’s yeast, Kluyveromyces marxianus CBS 6556, Saccharomyces cerevisiae CBS 7336, Lactobacillus reuteri DSM 20016), baker’s yeast provided the best yields and the highest enantiomeric ratios (95:5) in the bioreduction of the above ketones. In this respect, valuable chiral non-racemic functionalized oxygen-containing heterocycles (e.g., (S)-styrene oxide, (S)-2-phenyloxetane, (S)-2-phenyltetrahydrofuran), amenable to be further elaborated on, can be smoothly and successfully generated from their prochiral precursors. Studies about pure biocatalysts with mechanistical studies, application in different reactions, and new immobilization methods for improving their stability were reported in five different articles. The article by Su-Yan Wang et al. describes the cloning, expression, purification, and characterization of an N-acetylglucosamine 2-epimerase from Pedobacter heparinus (PhGn2E). For this, several N-acylated glucosamine derivatives were chemically synthesized and used to test the substrate specificity of the enzyme. The mechanism of the enzyme was studied by hydrogen/deuterium NMR. The study at the anomeric hydroxyl group and C-2 position of the substrate in the reaction mixture confirmed the epimerization reaction via ring-opening/enolate formation. Site-directed mutagenesis was also used to confirm the proposed mechanism of this interesting enzyme. The article by Forest H. Andrews et al. studies two enzymes, benzoylformate decarboxylase (BFDC) and pyruvate decarboxylase (PDC), which catalyze the non-oxidative decarboxylation of 2-keto acids with different specificity. BFDC from Pseudomonas putida exhibited very limited activity with pyruvate, whereas the PDCs from S. cerevisiae or from Zymomonas mobilis showed virtually no activity with benzoylformate (phenylglyoxylate). After studies using saturation mutagenesis, the BFDC T377L/A460Y variant was obtained, with 10,000-fold increase in pyruvate/benzoylformate. The change was attributed to an improvement in the Km value for pyruvate and a decrease in the kcat value for benzoylformate. The characterization of the new catalyst was performed, providing context for the observed changes in the specificity. The article by Xin Wang et al. compares two types of biocatalysts to produce D-lysine L-lysine in a cascade process catalyzed by two enzymes: racemase from microorganisms that racemize L-lysine to give D,L-lysine and decarboxylase that can be in cells, permeabilized cells, and the isolated enzyme. The comparison between the different forms demonstrated that the isolated enzyme showed the higher decarboxylase activity. Under optimal conditions, 750.7 mmol/L D-lysine was finally obtained from 1710 mmol/L L-lysine after 1 h of racemization reaction and 0.5 h of decarboxylation reaction. D-lysine yield could reach 48.8% with enantiomeric excess (ee) of 99%. In the article by Rivero and Palomo, lipase from Candida rugosa (CRL) was highly stabilized at alkaline pH in the presence of PEG, which permitted its immobilization for the first time by multipoint covalent attachment on different aldehyde-activated matrices. Different covalent immobilized preparation of the enzyme was successfully obtained. The thermal and solvent stability was highly increased by this treatment, and the novel catalysts showed high regioselectivity in the deprotection of per-O-acetylated nucleosides. The article by Robson Carlos Alnoch et al. describes the protocol and use of a new generation of tailor-made bifunctional supports activated with alkyl groups that allow the immobilization of proteins through the most hydrophobic region of the protein surface and aldehyde groups that allows the covalent immobilization of the previously adsorbed proteins. These supports were especially used in the case of lipase immobilization. The immobilization of a new metagenomic lipase (LipC12) yielded a biocatalyst 3.5-fold more active and 5000-fold more stable than the soluble enzyme. The PEGylated immobilized lipase showed high regioselectivity, producing high yields of the C-3 monodeacetylated product at pH 5.0 and 4 °C. Hybrid catalysts composed of an enzyme and metallic complex are also treated in this Special Issue. The article by Christian Herrero et al. describes the development of the Mn(TpCPP)-Xln10A artificial metalloenzyme, obtained by non-covalent insertion of Mn(III)-meso-tetrakis(p-carboxyphenyl)porphyrin [Mn(TpCPP), 1-Mn] into xylanase 10A from Streptomyces lividans (Xln10A). The complex was found able to catalyze the selective photo-induced oxidation of organic substrates in the presence of [RuII(bpy)3]2+ as a photosensitizer and [CoIII(NH3)5Cl]2+ as a sacrificial electron acceptor, using water as oxygen atom source. The two published reviews describe different subjects with interest in the fields of biocatalysis and mix metallic-biocatalysis, respectively. The review by Anika Scholtissek et al. describes the state-of-the-art regarding ene-reductases from the old yellow enzyme family (OYEs) to catalyze the asymmetric hydrogenation of activated alkenes to produce chiral products with industrial interest. The dependence of OYEs on pyridine nucleotide coenzyme can be avoided by using nicotinamide coenzyme mimetics. In the review, three main classes of OYEs are described and characterized. The review by Yajie Wang and Huimin Zhao highlights some of the recent examples in the past three years that combine transition metal catalysis with enzymatic catalysis. With recent advances in protein engineering, catalyst synthesis, artificial metalloenzymes, and supramolecular assembly, there is great potential to develop more sophisticated tandem chemoenzymatic processes for the synthesis of structurally complex chemicals. In conclusion, these nine publications give an overview of the possibilities of different catalysts, both traditional biocatalysts and hybrids with metals or organometallic complexes to be used in different processes—particularly in synthetic reactions—under very mild reaction conditions.

Coordination Chemistry of Silicon

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ISBN: 9783038976387 Year: Pages: 225 DOI: 10.3390/books978-3-03897-639-4 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Science (General) --- Chemistry (General) --- Inorganic Chemistry
Added to DOAB on : 2019-03-08 11:42:05
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The chemistry of silicon has always been a field of major concern due to its proximity to carbon on the periodic table. From the molecular chemist's viewpoint, one of the most interesting differences between carbon and silicon is their divergent coordination behavior. In fact, silicon is prone to form hyper-coordinate organosilicon complexes, and, as conveyed by reports in the literature, highly sophisticated ligand systems are required to furnish low-coordinate organosilicon complexes. Tremendous progress in experimental, as well as computational, techniques has granted synthetic access to a broad range of coordination numbers for silicon, and the scientific endeavor, which was ongoing for decades, was rewarded with landmark discoveries in the field of organosilicon chemistry. Molecular congeners of silicon(0), as well as silicon oxides, were unveiled, and the prominent group 14 metalloid proved its applicability in homogenous catalysis as a supportive ligand or even as a center of catalytic activity. This book focuses on the most recent advances in the coordination chemistry of silicon with transition metals as well as main group elements, including the stabilization of low-valent silicon species through the coordination of electron donor ligands. Therefore, this book is associated with the development of novel synthetic methodologies, structural elucidations, bonding analysis, and also possible applications in catalysis or chemical transformations using related organosilicon compounds.

Keywords

silanetriols --- disiloxane tetrols --- silsesquioxanes --- condensation --- molecular cage --- platinum --- primary silane --- hydrido complex --- oxidative addition --- ligand-exchange reaction --- X-ray crystallography --- Si–Cl activation --- germylene --- digermene --- digermacyclobutadiene --- palladium --- cluster --- cyclic organopolysilane --- template --- bridging silylene ligand --- isocyanide --- hydrogen bonds --- silicon --- 2-silylpyrrolidines --- stereochemistry --- X-ray crystallography --- Baird’s rule --- computational chemistry --- excited state aromaticity --- Photostability --- dye-sensitized solar cell --- disilanylene polymer --- photoreaction --- surface modification --- TiO2 --- silylene --- germylene --- N-heterocyclic carbene --- oxidative addition --- siloxanes --- host-guest chemistry --- supramolecular chemistry --- main group coordination chemistry --- hydrogen bonding --- adsorption --- bond activation --- bonding analysis --- density functional theory --- distorted coordination --- molecular orbital analysis --- silicon surfaces --- disilene --- functionalization --- ?-electron systems --- silicon --- N-heterocyclic carbenes --- bromosilylenes --- silyliumylidenes --- dehydrobromination --- silicon cluster --- siliconoid --- nanoparticle --- computation --- silicon --- N-heterocyclic carbenes --- silyliumylidenes --- small molecule activation --- mechanistic insights --- organosilicon --- reductant --- N-Heterocyclic tetrylene --- salt-free --- germanium --- germanethione --- germathioacid chloride --- N-heterocyclic carbines --- ?-chloro-?-hydrooligosilane --- titanium --- ruthenium --- dehydrogenative alkoxylation --- cluster --- isomerization --- silicon --- siliconoid --- subvalent compounds --- AIM --- DFT --- intermetallic bond --- 29Si NMR spectroscopy --- X-ray diffraction

Biotechnological Applications of Phage and Phage-Derived Proteins

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ISBN: 9783039214419 / 9783039214426 Year: Pages: 236 DOI: 10.3390/books978-3-03921-442-6 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Technology (General) --- General and Civil Engineering
Added to DOAB on : 2019-12-09 11:49:15
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Phages have shown a high biotechnological potential with numerous applications. The advent of high-resolution microscopy techniques aligned with omic and molecular tools have revealed innovative phage features and enabled new processes that can be further exploited for biotechnological applications in a wide variety of fields. The high-quality original articles and reviews presented in this Special Issue demonstrate the incredible potential of phages and their derived proteins in a wide range of biotechnological applications for human benefit. Considering the emergence of amazing new available bioengineering tools and the high abundance of phages and the multitude of phage proteins yet to be discovered and studied, we believe that the upcoming years will present us with many more fascinating and new previously unimagined phage-based biotechnological applications.

Keywords

gene expression regulation --- molecular probe --- macromolecular interactions --- phage-host interaction --- bacteriophage --- endolysin --- Clostridium perfringens --- alpha-sheet --- cancerous tumors --- capsid dynamics --- drug delivery vehicles --- native gel electrophoresis --- neurodegenerative disease --- pathogenic viruses --- phage display --- landscape phage --- major coat protein --- nanomedicine --- diagnostics --- biosensors --- M13 bacteriophage --- biofilm --- porous structure --- filters --- self-assembly --- T7phage library --- sarcoidosis --- tuberculosis --- microarray --- immunoscreening --- R-type pyocin --- bacteriocin --- contractile injection systems --- Pseudomonas aeruginosa --- X-ray crystallography --- receptor-binding protein --- Shigella flexneri --- bacteriophage --- tailspike proteins --- O-antigen --- serotyping --- microtiter plate assay --- fluorescence sensor --- bacteriophages --- encapsulation --- niosomes --- transfersomes --- liposomes --- Staphylococcus aureus --- phage --- Enterococcus faecalis --- Streptococcus agalactiae --- culture enrichment --- bacteriophage --- diagnostics --- Listeria monocytogenes --- endolysin --- magnetic separation --- reporter phage --- endolysin --- Pal --- Cpl-1 --- safety --- toxicity --- immune response --- Streptococcus pneumoniae --- self-assembly --- nanotubular structures --- tail sheath protein --- bacteriophage vB_EcoM_FV3 --- Appelmans --- bacteriophage evolution --- bacteriophage recombination --- phage therapy --- Pseudomonas aeruginosa --- antibiotic resistance --- bacteriophages --- Myoviridae --- bacteriophage-derived lytic enzyme --- enzybiotics --- endolysin --- in vitro activity --- ESKAPE --- n/a

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