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The literature review presents modern data on the intracellular antioxidant protection in the respiratory tract. The induction of the enzyme synthesis of antioxidant system is described. The article details the characteristics of the intracellular forms of superoxide dismutases. The induction of the synthesis, catalytic loop and physiological function of superoxide dismutases are presented.

Polysialic acids are bioactive carbohydrates found in eukaryotes and some bacterial pathogens. The bacterial polysialyltransferases (PSTs), which catalyze the synthesis of polysialic acid capsules, have previously been identified in select strains of Escherichia coli and Neisseria meningitidis and are classified in the Carbohydrate-Active enZYmes Database as glycosyltransferase family GT-38. In this study using DNA sequence analysis and functional characterization we have identified a novel polysialyltransferase from the bovine/ovine pathogen Mannheimia haemolytica A2 (PSTMh). The enzyme was expressed in recombinant form as a soluble maltose-binding-protein fusion in parallel with the related PSTs from E. coli K1 and N. meningitidis group B in order to perform a side-by-side comparison. Biochemical properties including solubility, acceptor preference, reaction pH optima, thermostability, kinetics, and product chain length for the enzymes were compared using a synthetic fluorescent acceptor molecule. PSTMh exhibited biochemical properties that make it an attractive candidate for chemi-enzymatic synthesis applications of polysialic acid. The activity of PSTMh was examined on a model glycoprotein and the surface of a neuroprogenitor cell line where the results supported its development for use in applications to therapeutic protein modification and cell surface glycan remodelling to enable cell migration at implantation sites to promote wound healing. The three PSTs examined here demonstrated different properties that would each be useful to therapeutic applications. © 2013 Lindhout et al.

Summary Glycolysis is a fundamental metabolic pathway for glucose catabolism across biology, and glycolytic enzymes are among the most abundant proteins in cells. Their expression at such levels provides a particular challenge. Here we demonstrate that the glycolytic mRNAs are localized to granules in yeast and human cells. Detailed live cell and smFISH studies in yeast show that the mRNAs are actively translated in granules, and this translation appears critical for the localization. Furthermore, this arrangement is likely to facilitate the higher level organization and control of the glycolytic pathway. Indeed, the degree of fermentation required by cells is intrinsically connected to the extent of mRNA localization to granules. On this basis, we term these granules, core fermentation (CoFe) granules; they appear to represent translation factories, allowing high-level coordinated enzyme synthesis for a critical metabolic pathway., Graphical abstract, Highlights • Glycolytic mRNAs colocalize and are translated in RNA granules • The glycolytic mRNA granules are important when cells are fermenting • Glycolytic protein translation is likely coordinated in these translation factories • Therefore, “CoFe granules” are core fermentation factories for glycolytic proteins, Molecular biology; cell biology

Huge quantities of apple orchard waste (AOW) generated could be regarded as a promising alternative energy source for fuel and material production. Conventional and traditional processes for disposal of these wastes are neither economical nor environment friendly. Hence, sustainable technologies are required to be developed to solve this long-term existence and continuous growing problem. In light of these issues, this review pays attention towards sustainable and renewable systems, various value-added products from an economic and environmental perspective. Refined bio-product derived from AOW contributes to resource and energy demand comprising of biomethane, bioethanol, biofuels, bio-fertilizers, biochar, and biochemicals, such as organic acid, and enzymes. However, the market implementation of biological recovery requires reliable process technology integrated with an eco-friendly and economic production chain, classified management., Graphical Abstract

Submitted by Marilene Donadel (marilene.donadel@unioeste.br) on 2020-10-01T14:08:44Z No. of bitstreams: 1 Ricardo_Zanella_2020.pdf: 1545208 bytes, checksum: e16418c58f4e4fe8c9833a69258d9875 (MD5) Made available in DSpace on 2020-10-01T14:08:44Z (GMT). No. of bitstreams: 1 Ricardo_Zanella_2020.pdf: 1545208 bytes, checksum: e16418c58f4e4fe8c9833a69258d9875 (MD5) Previous issue date: 2020-06-08 The main objective of this work was the enzymatic synthesis of ethyl oleate ester from fungal lipases, which was produced by the strain Penicillium sumatrense isolated from castor leaves (Ricinus communis L., Euphorbiaceae), and applying rice husks and Sunflower Seeds Bran (FSG) as substrates in Solid State Fermentation (FES). The dosage of the enzymatic activity was determined by the titrimetric method, using olive oil as a substrate. To maximize the production of lipases, experimental plans were carried out with different proportions of substrates and inductors (glycerol). A catalytic activity value of 29.3 Ugss-1 was obtained in the optimum conditions (55% humidity, 25% FSG, 27 ºC) in 96 h of fermentation. The fermented material (lipase) obtained from the agro-industrial residue of rice husks and sunflower seed bran, was used in the studies of the synthesis of ethyl oleate in n-heptane, modifying the variables of temperature, enzymatic activity and molar ratio (RM, acid: alcohol). To evaluate the ester yield, the Lowry & Tinsley spectrometric method was applied and the statistical analyzes were performed using the Statistica 7.0 software. The best experimental conditions for the enzymatic synthesis of ethyl oleate were obtained with the ground substrate, molar ratio 1:6 (acid/alcohol), temperature 37 ºC and enzymatic activity of 60 Ugss-1, reaching out 100% conversion to ester in 5 hours of reaction. Este trabalho teve como objetivo principal, a síntese enzimática do éster oleato de etila, a partir de lipases fúngicas, produzidas pela cepa Penicillium sumatrense, isolada das folhas da mamona (Ricinus communis L., Euphorbiaceae), e utilizando casca de arroz (CA) e farelo de sementes de girassol (FSG) como substratos na Fermentação em Estado Sólido (FES). A dosagem da atividade enzimática foi determinada pelo método titulométrico, utilizando o azeite de oliva com substrato. Em busca da maximização na produção de lipases, foram realizados planejamentos experimentais com diferentes proporções de substratos e indutores (glicerol). Os resultados obtidos indicaram uma atividade catalítica 29,3 Ugss-1 nas condições ótimas de 55% de umidade, 25% de FSG, 27 ºC em 96 h de fermentação. O material fermentado (lipase), obtido a partir do resíduo agroindustrial das cascas de arroz e farelo de semente de girassol, foi empregado nos estudos da síntese do éster oleato de etila em n-heptano, modificando as variáveis de temperatura, atividade enzimática e razão molar (RM, ácido:álcool). Para avaliar o rendimento em éster, foi utilizado o método espectrométrico de Lowry & Tinsley e as análises estatísticas foram realizadas pelo software Statistica 7.0. As melhores condições experimentais para a síntese enzimática do éster oleato de etila foram obtidas com o substrato moído, razão molar 1:6 (ácido/álcool), temperatura de 37 ºC e atividade enzimática de 60 Ugss-1, atingindo 100% de conversão em éster em 5 horas de reação.

The stringent response enables metabolic adaptation of bacteria under stress conditions and is governed by RelA/SpoT Homolog (RSH)-type enzymes. Long RSH-type enzymes encompass an N-terminal domain (NTD) harboring the second messenger nucleotide (p)ppGpp hydrolase and synthetase activity and a stress-perceiving and regulatory C-terminal domain (CTD). CTD-mediated binding of Rel to stalled ribosomes boosts (p)ppGpp synthesis. However, how the opposing activities of the NTD are controlled in the absence of stress was poorly understood. Here, we demonstrate on the RSH-type protein Rel that the critical regulative elements reside within the TGS (ThrRS, GTPase, and SpoT) subdomain of the CTD, which associates to and represses the synthetase to concomitantly allow for activation of the hydrolase. Furthermore, we show that Rel forms homodimers, which appear to control the interaction with deacylated-tRNA, but not the enzymatic activity of Rel. Collectively, our study provides a detailed molecular view into the mechanism of stringent response repression in the absence of stress.

Bioactive peptides are the small protein fragments, which have many positive benefits to mankind. Bioactive peptides are organic compounds formed of amino acids covalently attached by peptide bonds. However, some of them may exist freely in nature but most bioactive peptides are encrypted into the parent protein structure, which can be extracted or produced through processes like enzyme synthesis, chemical synthesis or microbial synthesis. Selection of production method depends upon the source from used for extraction of bioactive peptides. There is a wide range of sources for bioactive peptides production ranging from food products to marine and animal resources. These food resources are known to produce most efficient and health beneficial bioactive peptides. Bioactive peptides can be categorized on the basis of functional capabilities. Bioactive peptides contribute significantly toward human health by affecting the cardiovascular, digestive, immune, nervous and endocrine systems. Bioactive peptides can be produced only in a limited quantity using natural resources, which are not sufficient to meet growing need of bioactive peptides. To tackle this mismatch synthetic bioactive peptides are produced using biotechnological tools and processes. Synthetic bioactive peptides not only meet the required demand but they are also much more efficient than the conventional bioactive peptides. In this context, the present chapter will highlight about bioactive peptides, their sources, production techniques, major uses and biotechnological applications.

Circular nucleic acids with cyclic structure can greatly improve their stability towards exonucleases, which may endow special functions due to their cyclic structure. Limited by detection technology and instruments in early stage, researchers have relatively few studies on circular nucleic acids. In recent years, various kinds of circular nucleic acids have been discovered with the progress of science and technology and shown many unique physiological regulation functions in living organisms. However, it is still not clear whether the smaller ring oligonucleotides (dozens of bases) exist in life and have the potential functions. Here, we summary the two main kinds of synthesis methods (enzyme synthesis and chemical synthesis) of circular nucleic acid (especially smaller ring oligonucleotides), and compare their advantages and disadvantages. We also review the structural characteristics of various circular functional oligonucleotides and their effects on specific biological activities, especially the regulation of gene functions, which may provide a new tool to explore the chemical biology of circular nucleic acids in biological systems.

The emergence of carbapenemase-producing Enterobacteriaceae (CPE) is a critical concern worldwide. In Italy, CPE isolates are very frequent, with the KPC enzyme types strongly predominant whereas the New Delhi metallo-β-lactamase (NDM) enzymes are extremely rare. Here we report the first detection of NDM-5-producing Escherichia coli sequence type 167 (ST167) isolates from two patients with urinary tract infection (Ec001 and Ec002 from urines), including one with colonisation (Ec003 from faeces) admitted to the same hospital 2 months apart in 2017. Minimum inhibitory concentrations (MICs) were determined by broth microdilution. The carbapenemase type was identified both by phenotypic and genotypic methods. Isolate genotypes were investigated by phylogenetic typing, multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). Next-generation sequencing (NGS) was used to obtain complete sequences of plasmids. The three E. coli isolates carried the blaNDM-5 gene, shared the same resistance phenotype and belonged to ST167. By PFGE, isolates showed the same profile, suggesting that they were the same strain. NGS revealed that the blaNDM-5 gene was located on a 99-kb multireplicon plasmid (designed pNDM-5-IT) with a peculiar scaffold constituted by four replicons of the IncF type (FIA, FIB and two copies of the FII replicon). pNDM-5-IT plasmid harboured multiple resistance and virulence determinants, including the arginine deaminase (ADI) cluster never found associated with plasmids before. Since NDM-5-producing E. coli ST167 has been regarded as a successful epidemic clone in China, the emergence of such a clone carrying a plasmid associated both with multiresistance and virulence could be a public-health threat.

Diauxic growth of Escherichia coli is driven by a host of internal, complex regulatory actions. In this classic scenario of cellular control, the cell employs a rational algorithm to modulate its metabolism in a competitive fashion. Cybernetic models of metabolism, whose development now spans three decades, were first formulated to describe regulation of cells in complex, multi-substrate environments. They modeled this scenario using the hypothesis that the formation of the enzymatic machinery is regulated to maximize a return on investment. While this assumption is made on the basis of logical arguments rooted in evolutionary principles, little effort has been taken to validate if enzymes are truly synthesized in the same fashion that is predicted by cybernetic variables. This work revisits the original cybernetic models describing diauxic growth and compares their predictions of enzyme synthesis control with time series gene expression data in microarray and qRT-PCR formats. Three separate studies are made for two different strains of E. coli. The first is for the growth of E. coli BW25113 on a mixture of glucose and acetate, whose gene expression changes are metered by microarray. Another is also for the sequential consumption of glucose and acetate but involves strain MG1655 and employs qRT-PCR. The final is for E. coli MG1655 on glucose and lactose. By demonstrating how cybernetic variables for induced enzyme synthesis mimic the behavior of transcriptional data, a strong argument for using cybernetic models is made. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:858-867, 2018.

"An experiment with liquid nitrogen gave anomalous results, I proposed proton-ordered ice had contracted to accommodate water molecules' irregular tetrahedral shape. Recent reports of ice XIc at 72 K, below the ferroelectric transition temperature, confirmed it. Temperature fluctuations on primordial Earth’s poles released ice XIc's latent energy as ~4 m infrared laser light. After reflection by ice in clouds and on Earth's surface, it energized deoxynucleotides, turning Darwin's warm tropical waters to DNA noodle soup. "tRNA analogues, transport DNAs lined proto-cell membrane pores with H-bonds. Laser light drove a ratchet pump mechanism, concentrating substrates and promoting synthetic reactions within. Replicate t-DNAs marked life's origin. They elude detection, chromosomal DNA masks ~2,000/cell. A report of DNA particles around the entry of sperm to ovum might be verified. Differentiation DNAs selecting tDNAs determine tissue cell diet and metabolism, c.f. mRNAs selecting tRNAs for protein synthesis. Adequate trace elements tDNAs employ govern survival. "Twenty-one flat protein hairpins bind 189 base-pairs forming a ring, nine rings complete a minion. Minions pack chromosomes and ensure error-free replication. Their roles as biological clocks and chips in the brain explain psychology. Computers modeled on them promise human-friendly intelligence. They control nine metabolic pathways, predating enzyme synthesis. Adequate trace element nutrition promises better mental and physical health and longevity, public assurance of their safety is vital. "ATP's Pi~Pi bond stores~4 m wavelength energy, e.g. sarcomeres form ½-wave resonant cavities for muscle contraction. Oscillating H-bond chains accelerate protons along adjacent minion tunnels fast enough to fuse with obstructing nuclei. Trapping the g-rays released could provide clean power, resolving global warming. My proposals restore the simplicity and public trust in science prevailing c 1900 AD, reinterpreting quantum weirdness and cosmology would redirect funds to conservation, humanitarian projects and diplomacy, ensuring a happy future."

Glycolysis represents the fundamental metabolic pathway for glucose catabolism across biology, and glycolytic enzymes are amongst the most abundant proteins in cells. Their expression at such levels provides a particular challenge. Here we demonstrate that the glycolytic mRNAs are localized to granules in yeast and human cells. Detailed live cell and smFISH studies in yeast show that the mRNAs are actively translated in granules, and this translation appears critical for the localization. Furthermore, this arrangement is likely to facilitate the higher level organisation and control of the glycolytic pathway. Indeed, the degree of fermentation required by cells seems intrinsically connected to the extent of mRNA localization to granules. On this basis, we have termed the granules, Core Fermentation (CoFe) granules. Therefore, glycolytic mRNA granules likely represent a conserved means to maintain high-level co-ordinated enzyme synthesis for a critical metabolic pathway.

Microbial cells need to adapt to changing environmental conditions to survive. There is an evolutionary advantage to grow fast; this requires high metabolic rates, and an efficient allocation of enzymatic resources. Here we study a general control theory called qORAC, developed previously, which allows cells to adaptively control their enzyme allocations to achieve maximal steady state flux. The control is robust to perturbations in the environment, but those perturbations themselves do not feature in the control. In this paper we focus on the archetypical pathway, the linear chain with reversible Michaelis-Menten kinetics, together with qORAC control. First we assume that the metabolic pathway is in quasi-steady state with respect to enzyme synthesis. Then we show that the map between steady state metabolite and enzyme concentrations is a smooth bijection. Using this information, we finally show that the unique (and hence flux-maximising) steady state of this system is locally stable. We provide further evidence that it may in fact be globally stable.

Microbial lipases are prominent biocatalysts able to catalyze a wide variety of reactions in aqueous and nonaqueous media. In this work, filamentous fungi isolated from leaves decomposed in an aquatic environment were screened for lipase production with hydrolytic activity and esterification. Agar plates with Tween 20 and Rhodamine B were used for selection, while submerged cultures with olive oil were subsequently used to select 38 filamentous fungi. Trichoderma harzianum, Fusarium solani, Trichoderma harzianum F5, and Penicillium sp. F36 were grown in six different culture media. F. solani presented the highest lipase production (2.37 U/mL) with esterification activity of 0.07 U/mL using medium composed of (g.L−1) KH2PO4 1.00, MgSO4 H2O 1.123, and CuSO4 0.06. Supplementation of this culture medium with organic nitrogen sources increased lipase production by 461.3% using tryptone and by 419.4% using yeast extract. Among the vegetable oils from the Amazon region, degummed cotton oil induced lipase production up to 8.14 U/mL. The lipase produced by F. solani F61 has great potential to application in conventional processes and biodiesel production by transesterification of vegetable oils, as well as food industries in the production of fatty acid esters by hydrolysis and esterification.

Trauma is the most common cause of mortality among individuals aged between 1 and 44 years and the third leading cause of mortality overall in the US. In this study, we examined the effects of trauma on the expression of genes in Drosophila melanogaster, a useful model for investigating genetics and physiology. After trauma was induced by a non-lethal needle puncture of the thorax, we observed the differential expression of genes encoding for mitochondrial uncoupling proteins, as well as those encoding for apoptosis-related and insulin signaling-related proteins, thus indicating muscle functional dysregulation. These results prompted us to examine the link between insulin signaling and mitochondrial dysfunction using in vivo nuclear magnetic resonance (NMR) with complementary electron paramagnetic resonance (EPR) spectroscopy. Trauma significantly increased insulin resistance biomarkers, and the NMR spectral profile of the aged flies with trauma-induced thoracic injury resembled that of insulin-resistant chico mutant flies. In addition, the mitochondrial redox status, as measured by EPR, was significantly altered following trauma, indicating mitochondrial uncoupling. A mitochondria-targeted compound, Szeto-Schiller (SS)-31 that promotes adenosine triphosphate (ATP) synthesis normalized the NMR spectral profile, as well as the mitochondrial redox status of the flies with trauma-induced thoracic injury, as assessed by EPR. Based on these findings, we propose a molecular mechanism responsible for trauma-related mortality and also propose that trauma sequelae in aging are linked to insulin signaling and mitochondrial dysfunction. Our findings further suggest that SS-31 attenuates trauma-associated pathological changes. 37 299 308

Methods for synthesizing arbitrary single-strand DNA (ssDNA) fragments are rapidly becoming fundamental tools for gene editing, DNA origami, DNA storage, and other applications. To meet the rising application requirements, numerous methods have been developed to produce ssDNA. Some approaches allow the synthesis of freely chosen user-defined ssDNA sequences to overcome the restrictions and limitations of different length, purity, and yield. In this perspective, we provide an overview of the representative ssDNA production strategies and their most significant challenges to enable the readers to make informed choices of synthesis methods and enhance the availability of increasingly inexpensive synthetic ssDNA. We also aim to stimulate a broader interest in the continued development of efficient ssDNA synthesis techniques and improve their applications in future research.