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Yeast Biotechnology

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ISBN: 9783038424437 9783038424420 Year: Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Biology
Added to DOAB on : 2017-06-28 09:30:16
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Yeasts are truly fascinating microorganisms. Due to their diverse and dynamic activities, they have been used for the production of many interesting products, such as beer, wine, bread, biofuels, and biopharmaceuticals. Saccharomyces cerevisiae (brewers’ or bakers’ yeast) is the yeast species that is surely the most exploited by man. Saccharomyces is a top choice organism for industrial applications, although its use for producing beer dates back to at least the 6th millennium BC. Bakers’ yeast has been a cornerstone of modern biotechnology, enabling the development of efficient production processes. Today, diverse yeast species are explored for industrial applications. This Special Issue is focused on some recent developments of yeast biotechnology, i.e., bioethanol, wine and beer, and enzyme production. Additionally, the new field of yeast nanobiotechnology is introduced and reviewed.

Non-conventional Yeast in the Wine Industry

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889450534 Year: Pages: 177 DOI: 10.3389/978-2-88945-053-4 Language: English
Publisher: Frontiers Media SA
Subject: Microbiology --- Science (General)
Added to DOAB on : 2017-07-06 13:27:36
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Saccharomyces cerevisiae strains that exhibit high ethanol tolerance and excellent fermentative ability are extensively used in winemaking as selected starters. However, a side-effect of the widespread use of these commercial starter cultures is the elimination of native microbiota, which might result in wines with similar analytical and sensory properties, depriving them from the variability, complexity and personality that define the typicality of a wine. Nonetheless, a way of balancing control and yeast population diversity during wine fermentation is the selection of non-Saccharomyces yeasts with optimal oenological traits. Therefore, a current trend in enology is the implementation of mixed- or multi-starters cultures, combining S. cerevisiae that remains the yeast species required for the completion of fermentation and non-Saccharomyces yeasts isolated from the native flora of grape juices. This research topic mainly deals with possible applications of different non-Saccharomyces yeast to wine production such as aroma production, ethanol reduction or biocontrol.Saccharomyces cerevisiae strains that exhibit high ethanol tolerance and excellent fermentative ability are extensively used in winemaking as selected starters. However, a side-effect of the widespread use of these commercial starter cultures is the elimination of native microbiota, which might result in wines with similar analytical and sensory properties, depriving them from the variability, complexity and personality that define the typicality of a wine. Nonetheless, a way of balancing control and yeast population diversity during wine fermentation is the selection of non-Saccharomyces yeasts with optimal oenological traits. Therefore, a current trend in enology is the implementation of mixed- or multi-starters cultures, combining S. cerevisiae that remains the yeast species required for the completion of fermentation and non-Saccharomyces yeasts isolated from the native flora of grape juices. This research topic mainly deals with possible applications of different non-Saccharomyces yeast to wine production such as aroma production, ethanol reduction or biocontrol.

Emerging Functions of Septins

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889452873 Year: Pages: 126 DOI: 10.3389/978-2-88945-287-3 Language: English
Publisher: Frontiers Media SA
Subject: Science (General) --- Biology
Added to DOAB on : 2018-02-27 16:16:44
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Together with the microfilament, microtubule and intermediate-filament networks, septins constitute an integral part of the eukaryotic cytoskeleton. Historically identified as proteins critical for septum formation in the budding yeast Saccharomyces cerevisiae, septin family GTPases are expressed and participate in the process of cytokinesis in most eukaryotes except higher plants. More than a dozen septin genes in mammals, together with various splice variants displaying tissue-specific expression patterns and flexible hetero-polymeric higher-order assembly achieve an unfathomable complexity superior to the other cytoskeletal components. Even though the initial studies in the septin field was restricted to their evolutionarily conserved role in cell division, strong expression of septins in the non-dividing cells of the brain generated great interest in understanding their role in neuronal morphogenesis and other aspects of cellular function. On one hand, recent developments indicate complex non-canonical roles for septins in diverse processes ranging from neuronal development to immune response and calcium signaling. On the other hand several lines of data including those from knockout models question the universal role for septins in animal cell cytokinesis. Mammalian hematopoietic cells seem to proliferate and efficiently undergo cytokinesis in the absence of pivotal septin proteins in a context-dependent manner. The lack of septin-dependence of hematopoiesis also opens the possibility of safely targeting septin-dependent cytokinesis for solid-tumor therapy. Thus the septin field is perfectly poised with novel roles for septins being discovered and the basic understanding on septin assembly and its canonical functions constantly revisited. The objective of this research topic was to provide an exclusive platform for discussing these rapid advances in the septin field. With a mixture of reviews and research articles encompassing diverse areas of septin research, ranging from the humble yeast model to human cancer, this ebook will be an interesting reading material for both experts as well as new comers to the septin field.

Keywords

septin --- cytokinesis --- Cilia --- mutation --- GTPase --- cytoskeleton --- yeast --- budding --- SOCE --- cancer

Recombinant protein expression in microbial systems

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889192946 Year: Pages: 102 DOI: 10.3389/978-2-88919-294-6 Language: English
Publisher: Frontiers Media SA
Subject: Environmental Sciences --- Biotechnology --- General and Civil Engineering --- Microbiology --- Science (General)
Added to DOAB on : 2015-12-10 11:59:07
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With the advent of recombinant DNA technology, expressing heterologous proteins in microorganisms rapidly became the method of choice for their production at laboratory and industrial scale. Bacteria, yeasts and other hosts can be grown to high biomass levels efficiently and inexpensively. Obtaining high yields of recombinant proteins from this material was only feasible thanks to constant research on microbial genetics and physiology that led to novel strains, plasmids and cultivation strategies. Despite the spectacular expansion of the field, there is still much room for progress. Improving the levels of expression and the solubility of a recombinant protein can be quite challenging. Accumulation of the product in the cell can lead to stress responses which affect cell growth. Buildup of insoluble and biologically inactive aggregates (inclusion bodies) lowers the yield of production. This is particularly true for obtaining membrane proteins or high-molecular weight and multi-domain proteins. Also, obtaining eukaryotic proteins in a prokaryotic background (for example, plant or animal proteins in bacteria) results in a product that lack post-translational modifications, often required for functionality. Changing to a eukaryotic host (yeasts or filamentous fungi) may not be a proper solution since the pattern of sugar modifications is different than in higher eukaryotes. Still, many advances in the last couple of decades have provided to researchers a wide variety of strategies to maximize the production of their recombinant protein of choice. Everything starts with the careful selection of the host. Be it bacteria or yeast, a broad list of strains is available for overcoming codon use bias, incorrect disulfide bond formation, protein toxicity and lack of post-translational modifications. Also, a huge catalog of plasmids allows choosing for different fusion partners for improving solubility, protein secretion, chaperone co-expression, antibiotic resistance and promoter strength. Next, controlling culture conditions like temperature, inducer and media composition can bolster recombinant protein production. With this Research Topic, we aim to provide an encyclopedic account of the existing approaches to the expression of recombinant proteins in microorganisms, highlight recent discoveries and analyze the future prospects of this exciting and ever-growing field.

DNA Replication Origins in Microbial Genomes

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889197798 Year: Pages: 115 DOI: 10.3389/978-2-88919-779-8 Language: English
Publisher: Frontiers Media SA
Subject: Microbiology --- Science (General)
Added to DOAB on : 2016-04-07 11:22:02
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DNA replication, a central event for cell proliferation, is the basis of biological inheritance. Complete and accurate DNA replication is integral to the maintenance of the genetic integrity of organisms. In all three domains of life, DNA replication begins at replication origins. In bacteria, replication typically initiates from a single replication origin (oriC), which contains several DnaA boxes and the AT-rich DNA unwinding element (DUE). In eukaryotic genomes, replication initiates from significantly more replication origins, activated simultaneously at a specific time. For eukaryotic organisms, replication origins are best characterized in the unicellular eukaryote budding yeast Saccharomyces cerevisiae and the fission yeast Schizosaccharomyces pombe. The budding yeast origins contain an essential sequence element called the ARS (autonomously replicating sequence), while the fission yeast origins consist of AT-rich sequences. Within the archaeal domain, the multiple replication origins have been identified by a predict-and-verify approach in the hyperthermophilic archaeon Sulfolobus. The basic structure of replication origins is conserved among archaea, typically including an AT-rich unwinding region flanked by several short repetitive DNA sequences, known as origin recognition boxes (ORBs). It appears that archaea have a simplified version of the eukaryotic replication apparatus, which has led to considerable interest in the archaeal machinery as a model of that in eukaryotes. The research on replication origins is important not only in providing insights into the structure and function of the replication origins but also in understanding the regulatory mechanisms of the initiation step in DNA replication. Therefore, intensive studies have been carried out in the last two decades. The pioneer work to identify bacterial oriCs in silico is the GC-skew analysis. Later, a method of cumulative GC skew without sliding windows was proposed to give better resolution. Meanwhile, an oligomer-skew method was also proposed to predict oriC regions in bacterial genomes. As a unique representation of a DNA sequence, the Z-curve method has been proved to be an accurate and effective approach to predict bacterial and archaeal replication origins. Budding yeast origins have been predicted by Oriscan using similarity to the characterized ones, while the fission yeast origins have been identified initially from AT content calculation. In comparison with the in silico analysis, the experimental methods are time-consuming and labor-intensive, but convincing and reliable. To identify microbial replication origins in vivo or in vitro, a number of experimental methods have been used including construction of replicative oriC plasmids, microarray-based or high-throughput sequencing-based marker frequency analysis, two-dimensional gel electrophoresis analysis and replication initiation point mapping (RIP mapping). The recent genome-wide approaches to identify and characterize replication origin locations have boosted the number of mapped yeast replication origins. In addition, the availability of increasing complete microbial genomes and emerging approaches has created challenges and opportunities for identification of their replication origins in silico, as well as in vivo and in vitro. The Frontiers in Microbiology Research Topic on DNA replication origins in microbial genomes is devoted to address the issues mentioned above, and aims to provide a comprehensive overview of current research in this field.

Wine Fermentation

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ISBN: 9783038976745 Year: Pages: 176 DOI: 10.3390/books978-3-03897-675-2 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Biotechnology --- Technology (General)
Added to DOAB on : 2019-04-05 11:07:22
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This book is a printed edition of the Special Issue Wine Fermentation that was published in Fermentation

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.

Fungal Infections in Immunocompromised Hosts

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ISBN: 9783038977162 Year: Pages: 212 DOI: 10.3390/books978-3-03897-717-9 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Microbiology --- Biology --- Science (General)
Added to DOAB on : 2019-04-05 10:34:31
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This book is a printed edition of the Special Issue Fungal Infections in Immunocompromised Hosts that was published in JoF

Keywords

Candida auris --- Aspergillus fumigatus --- antifungal resistance --- multidrug resistance --- mechanisms of antifungal resistance --- liver disease --- hepatic impairment --- invasive fungal infection --- antifungal agent --- antifungal drug --- toxicity --- Immunotherapy --- invasive aspergillosis --- Aspergillus fumigatus --- fungal infections --- innate immunity --- adaptive immunity --- cell therapy --- cytokine therapy --- taxonomy --- fungal nomenclature --- phylogenetics --- species complex --- invasive fungal infections --- mycoses --- immune reconstitution inflammatory syndrome --- fungal immunity --- prognostic risk model --- prediction models --- risk score --- invasive mold disease --- hematological malignancy --- risk assessment --- antifungal stewardship --- paracoccidioidomycosis --- HIV --- cancer --- lymphoma --- kidney transplant --- TNF inhibitors --- literature review --- MALDI-ToF MS --- yeast --- fungus --- AIDS --- IRIS --- cat-transmitted sporotrichosis --- immunocompromised hosts --- mycoses of implantation --- sporotrichosis --- Sporothrix brasiliensis --- Sporothrix schenckii --- subcutaneous mycoses --- invasive fungal infection --- non-culture-based diagnostics --- aspergillosis --- candidiasis --- Aspergillus PCR --- galactomannan --- lateral flow --- beta-d-glucan --- T2 Candida --- candidemia --- Candida meningoencephalitis --- (1?3)-?-d-glucan --- T2Candida --- PCR --- liposomal amphotericin B --- micafungin --- anidulafungin --- Aspergillus --- anti-fungal agents --- hematological malignancies

TRP Channels in Health and Disease

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ISBN: 9783039210824 / 9783039210831 Year: Pages: 266 DOI: 10.3390/books978-3-03921-083-1 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Medicine (General)
Added to DOAB on : 2019-06-26 08:44:07
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Almost 25 years ago, the first mammalian transient receptor potential (TRP) channel was cloned and published. TRP channels now represent an extended family of 28 members fulfilling multiple roles in the living organism. Identified functions include control of body temperature, transmitter release, mineral homeostasis, chemical sensing, and survival mechanisms in a challenging environment. The TRP channel superfamily covers six families: TRPC with C for “canonical”, TRPA with A for “ankyrin”, TRPM with M for “melastatin”, TRPML with ML for “mucolipidin”, TRPP with P for “polycystin”, and TRPV with V for “vanilloid”. Over the last few years, new findings on TRP channels have confirmed their exceptional function as cellular sensors and effectors. This Special Book features a collection of 8 reviews and 7 original articles published in “Cells” summarizing the current state-of-the-art on TRP channel research, with a main focus on TRP channel activation, their physiological and pathophysiological function, and their roles as pharmacological targets for future therapeutic options.

Keywords

ion channel --- TRPC --- small molecules --- calcium --- chemical probes --- TRPV1 --- TRPV2 --- TRPV3 --- TRPV4 --- mucosal epithelium --- ulcerative colitis --- inflammatory bowel disease --- TRPM4 channel --- cardiovascular system --- physiology --- pathophysiology --- TRPC6 --- elementary immunology --- inflammation --- calcium --- sodium --- neutrophils --- lymphocytes --- endothelium --- platelets --- human medulla oblongata --- cuneate nucleus --- dorsal column nuclei --- TRPV1 --- calcitonin gene-related peptide --- substance P --- TRP channels --- calcium signaling --- salivary glands --- xerostomia --- radiation --- inflammation --- transient receptor potential channels --- TRPC3 pharmacology --- channel structure --- lipid mediators --- photochromic ligands --- transient receptor potential --- TRPC3 --- mGluR1 --- GABAB --- EPSC --- Purkinje cell --- cerebellum --- toxicology --- TRP channels --- organ toxicity --- chemicals --- pollutants --- chemosensor --- TRPM7 --- kinase --- inflammation --- lymphocytes --- calcium signalling --- SMAD --- TH17 --- hypersensitivity --- regulatory T cells --- thrombosis --- graft versus host disease --- 2D gel electrophoresis --- AP18 --- HEK293 --- HSP70 --- MALDI-TOF MS(/MS) --- nanoHPLC-ESI MS/MS --- proteomics --- sulfur mustard --- TRPA1 --- TRPC channels --- diacylglycerol --- TRPC4 --- TRPC5 --- NHERF --- TRP channel --- TRPY1 --- Saccharomyces cerevisiae --- calcium --- manganese --- oxidative stress --- ion channels --- overproduction --- production platform --- protein purification --- Saccharomyces cerevisiae --- sensors --- transient receptor potential (TRP) channels --- yeast --- adipose tissue --- bioavailable --- menthol --- topical --- TRPM8 --- n/a

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