NamZ1 and NamZ2 from the oral pathogen Tannerella forsythia are peptidoglycan processing exo-β-N-acetylmuramidases with distinct substrate specificity

ABSTRACTThe Gram-negative periodontal pathogen Tannerella forsythia is inherently auxotrophic for N-acetylmuramic acid (MurNAc), which is an essential carbohydrate constituent of the peptidoglycan (PGN) of the bacterial cell wall. Thus, to build up its cell wall, T. forsythia strictly depends on the salvage of exogenous MurNAc or sources of MurNAc, such as polymeric or fragmentary PGN, derived from cohabiting bacteria within the oral microbiome. In our effort to elucidate how T. forsythia satisfies its demand for MurNAc, we recognized that the organism possesses three putative orthologs of the exo-β-N-acetylmuramidase BsNamZ from Bacillus subtilis, which cleaves non-reducing end, terminal MurNAc entities from the artificial substrate pNP-MurNAc and the naturally-occurring disaccharide substrate MurNAc-β-1,4-N-acetylglucosamine (GlcNAc). TfNamZ1 and TfNamZ2 were successfully purified as soluble, pure recombinant His6-fusions and characterized as exo-lytic β-N-acetylmuramidases with distinct substrate specificities. The activity of TfNamZ1 was considerably lower compared to TfNamZ2 and BsNamZ, in the cleavage of pNP-MurNAc and MurNAc-GlcNAc. When peptide-free PGN glycans were used as substrates, we revealed striking differences in the specificity and mode of action of these enzymes, as analyzed by mass spectrometry. TfNamZ1, but not TfNamZ2 or BsNamZ, released GlcNAc-MurNAc disaccharides from these glycans. In addition, glucosamine (GlcN)-MurNAc disaccharides were generated when partially N-deacetylated PGN glycans from B. subtilis 168 were applied. This characterizes TfNamZ1 as a unique disaccharide-forming exo-lytic β-N-acetylmuramidase (exo-disaccharidase), and, TfNamZ2 and BsNamZ as sole MurNAc monosaccharide-lytic exo-β-N-acetylmuramidases.IMPORTANCETwo exo-β-N-acetylmuramidases from T. forsythia belonging to glycosidase family GH171 (www.cazy.org) were shown to differ in their activities, thus revealing a functional diversity within this family: NamZ1 releases disaccharides (GlcNAc-MurNAc/GlcN-MurNAc) from the non-reducing ends of PGN glycans, whereas NamZ2 releases terminal MurNAc monosaccharides. This work provides a better understanding of how T. forsythia may acquire the essential growth factor MurNAc by the salvage of PGN from cohabiting bacteria in the oral microbiome, which may pave avenues for the development of anti-periodontal drugs. On a broad scale, our study indicates that the utilization of PGN as a nutrient source, involving exo-lytic N-acetylmuramidases with different modes of action, appears to be a general feature of bacteria, particularly among the phylum Bacteroidetes.

Effect of Gibberellic Acid (GA3) on the Yield Attributing Traits during a Cold Period in Rice

Gibberellic acid is an essential growth promoter that aids in the systematic plant growth. Studies on the impact of GA3 during cold period discovered a positive effect on the growth of rice plants. The current study evaluated the impact of various concentrations of GA3 on the yielding attributes of rice during cold stress in the rice varities, JGL 1804, BPT 5204, and RNR 15048. All the quantitative traits showed significant variation among the genotypes and treatments. Gibberellins applied at low concentrations during seedling stage (1, 2 or 3 gm/200 m2 of nursery area) revealed higher quantitative trait values compared to higher concnetartions (5 and 10 gm). Among all the three varities, RNR 15048 was found to be the best variety than the others in terms of yielding triats. Therefore, GA3 applied at a concentration of 1gm, 2gm or 3gm promotes the rice plant growth during cold periods and results in higher yield. Among these, 2 gm of GA3 for 200 m2 of nurcessary area was found to be the best in aiding the crop growth during cold phase.

Riboflavin instability is a key factor underlying the requirement of a gut microbiota for mosquito development

We previously determined that several diets used to rear Aedes aegypti and other mosquito species support the development of larvae with a gut microbiota but do not support the development of axenic larvae. In contrast, axenic larvae have been shown to develop when fed other diets. To understand the mechanisms underlying this dichotomy, we developed a defined diet that could be manipulated in concert with microbiota composition and environmental conditions. Initial studies showed that axenic larvae could not grow under standard rearing conditions (27 °C, 16-h light: 8-h dark photoperiod) when fed a defined diet but could develop when maintained in darkness. Downstream assays identified riboflavin decay to lumichrome as the key factor that prevented axenic larvae from growing under standard conditions, while gut community members like Escherichia coli rescued development by being able to synthesize riboflavin. Earlier results showed that conventional and gnotobiotic but not axenic larvae exhibit midgut hypoxia under standard rearing conditions, which correlated with activation of several pathways with essential growth functions. In this study, axenic larvae in darkness also exhibited midgut hypoxia and activation of growth signaling but rapidly shifted to midgut normoxia and arrested growth in light, which indicated that gut hypoxia was not due to aerobic respiration by the gut microbiota but did depend on riboflavin that only resident microbes could provide under standard conditions. Overall, our results identify riboflavin provisioning as an essential function for the gut microbiota under most conditions A. aegypti larvae experience in the laboratory and field.

Therapeutic and Biomedical Potentialities of Terpenoids – A Review

Terpenoids are the most diverse and largest class of chemicals of the innumerable plant-based compounds. Plants carry out a number of essential growth and production functions using terpenoid metabolites. In contrast, most terpenoids are used in the abiotic and biotic systems for complex chemical interactions and defense. Terpenoids derived from plants mostly used humans for pharmaceutical, food, and chemical industries in the past. However, recently biofuel products have been developed by terpenoids. The metabolism of high-quality terpenoids in plants and microbes is facilitated in synthetic biology by genomic resources and emerging tools. Further focus has been given to the ecological value of terpenoids for establishing effective pesticide control approaches and abiotic stress protection. The awareness of the diverse metabolic and molecular regulatory networks for terpenoid biosynthesis needs to be increased continuously in all these efforts. This review gives an overview and highlights current improvements in our understanding of the organization, regulation, and diversification of core and specialized terpenoid metabolic pathways and discusses the prominent therapeutic roles of terpenoids. This review provides an overview and highlights recent literature in our understanding about the biomedical and therapeutic importance of terpenoids, regulation as well as the diversion of core and specialized metabolized terpenoid pathways.

Plasma-Rich in Growth Factor and its Clinical Application

The potential use of growth factors in stem cell-based therapies for the repair and regeneration of tissues and organs offers a paradigm shift in regenerative medicine. Growth factors are critical signalling molecules that play an important role in tissue development and remodelling. Plasma Rich in Growth Factor (PRGF) is a biotechnological strategy for the harvesting of the active substances of platelets, including growth factors, from the patient’s blood. Because of their tremendous essential growth factor and bioactive agents, as well as their paracrine mechanisms, PRGF has been used as an efficacious option and adjuvant biological therapy in the repair and replacement of damaged organs. This article provides an overview of PRGF extraction and its properties and critically reviewed its clinical benefit and clinical trials in the treatment and regeneration of human organs. Regenerative medicine is a multi-billion-dollar industry with huge interest to clinicians, academics and industries, being considered as an emerging technology.

Editorial — Systems Biology Approach for Identification of Essential Growth Factors in Retinal Regeneration

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INVESTIGATION OF THE INFLUENCE OF UHF ELECTROMAGNETIC FIELD ON THE OUTPUT OF ROLLED GROATS OF WHEAT SPELT

Wheat spelt is a promising crop. A high food value and high-quality biochemical composition of grains make wheat spelt favorably remarkable for groats production. Preservation of the food value is an important task of food production, but regimes of grain processing must provide good culinary quality and consumption safety. The aim of our work is to study regimes of irradiation and humidification of wheat spelt grains, influencing the output and culinary quality of the ready product; development of recommendations as to production of rolled groats. There is studied an influence of different regimes of water-thermal processing on the total output of groats and rolled groats of the highest sort. The reliable connection between the output of rolled groats of the higher sort and duration of irradiation by the electromagnetic field of the ultrahigh frequency and grain humidification has been established. No essential connection as been established between humidification and the total output of groats. The duration increase of UHF-irradiation (>120–140 s) conditions the essential growth of dust middlings and decrease of rolled groats of the highest sort. The long-term irradiation (180 s) conditions the decrease of groats boiling duration by 17 % comparing with the short-term processing (20 s). The established influences of the factors are preconditions for transferring obtained technological solutions and their use under conditions of existing groats factories of different productivity

The nucleocytosolic O-fucosyltransferase Spindly affects protein expression and virulence in Toxoplasma gondii

Once considered unusual, nucleocytoplasmic glycosylation is now recognized as a conserved feature of eukaryotes. While in animals O-GlcNAc transferase (OGT) modifies thousands of intracellular proteins, the human pathogen Toxoplasma gondii transfers a different sugar, fucose, to proteins involved in transcription, mRNA processing and signaling. Knockout experiments showed that TgSPY, an ortholog of plant SPINDLY and paralog of host OGT, is required for nuclear O-fucosylation. Here we verify that TgSPY is the nucleocytoplasmic O-fucosyltransferase (OFT) by 1) complementation with TgSPY-MYC3, 2) its functional dependence on amino acids critical for OGT activity, and 3) its ability to O-fucosylate itself and a model substrate and to specifically hydrolyze GDP-Fuc. While many of the endogenous proteins modified by O-Fuc are important for tachyzoite fitness, O-fucosylation by TgSPY is not essential. Growth of Δspy tachyzoites in fibroblasts is modestly affected, despite marked reductions in the levels of ectopically-expressed proteins normally modified with O-fucose. Intact TgSPY-MYC3 localizes to the nucleus and cytoplasm, whereas catalytic mutants often displayed reduced abundance. Δspy tachyzoites of a luciferase-expressing type II strain exhibited infection kinetics in mice similar to wild type but increased persistence in the chronic brain phase, potentially due to an imbalance of regulatory protein levels. The modest changes in parasite fitness in vitro and in mice, despite profound effects on reporter protein accumulation, and the characteristic punctate localization of O-fucosylated proteins, suggest that TgSPY controls the levels of proteins to be held in reserve for response to novel stresses.

The nucleocytosolic O-fucosyltransferase Spindly affects protein expression and virulence in Toxoplasma gondii

Once considered unusual, nucleocytoplasmic glycosylation is now recognized as a conserved feature of eukaryotes. While in animals O-GlcNAc transferase (OGT) modifies thousands of intracellular proteins, the human pathogen Toxoplasma gondii transfers a different sugar, fucose, to proteins involved in transcription, mRNA processing and signaling. Knockout experiments showed that TgSPY, an ortholog of plant SPINDLY and paralog of host OGT, is required for nuclear O-fucosylation. Here we verify that TgSPY is the nucleocytoplasmic O-fucosyltransferase (OFT) by 1) complementation with TgSPY-MYC3, 2) its functional dependence on amino acids critical for OGT activity, and 3) its ability to O-fucosylate itself and a model substrate and to specifically hydrolyze GDP-Fuc. While many of the endogenous proteins modified by O-Fuc are important for tachyzoite fitness, O-fucosylation by TgSPY is not essential. Growth of Δspy tachyzoites in fibroblasts is modestly affected, despite marked reductions in the levels of ectopically-expressed proteins normally modified with O-fucose. Intact TgSPY-MYC3 localizes to the nucleus and cytoplasm, whereas catalytic mutants often displayed reduced abundance. Δspy tachyzoites of a luciferase-expressing type II strain exhibited infection kinetics in mice similar to wild type but increased persistence in the chronic brain phase, potentially due to an imbalance of regulatory protein levels. The modest changes in parasite fitness in vitro and in mice, despite profound effects on reporter protein accumulation, and the characteristic punctate localization of O-fucosylated proteins, suggest that TgSPY controls the levels of proteins to be held in reserve for response to novel stresses.

МОДЕЛИРОВАНИЕ ИЗМЕНЕНИЙ В ГЕОМЕТРИИ КРЫЛА ПРИ ИХ СОГЛАСОВАНИИ С ПАРАМЕТРАМИ СИЛОВОЙ УСТАНОВКИ

Development modifications of aircraft have become the main direction of development of transport category airplanes, including military transport (МTА). However, there are several ways to solve such tasks:– to leave the same area and other geometric parameters of the wing and the problem are solved by significant changes in the power plant;– change the wing area and the aerodynamic configuration with the same parameters of the power plant.Both these ways have their advantages, but their implementation raises a number of problematic issues:- excessive growth of the starting mass modification;- the deterioration of its takeoff and landing characteristics;- deterioration in fuel efficiency and other technical and economic indicators, which leads to a decrease in the competitiveness of the modification.The most effective is getting the new aircraft when an agreement is called, changes are already in the preliminary design phase of the modification.The article formed the scheme of approval of such changes, with the essential growth of the load capacity, range, and improved fuel efficiency of the designed modifications. A distinctive feature of the proposed scheme is that modification changes the geometry of the wing reduces the magnitude of its inductive reactance at a predetermined lifting force.A model of the influence of design changes in the geometry of the wing, such as the narrowing and the corners of the geometric twist of the local chord along the span, expressed via the coefficients of the ellipticity of the trapezoidal wing, to change the polars of the wing and its aerodynamic quality.Developed a step-by-step evaluation of the aerodynamic performance of the required values of the coefficients and , the magnitude of which is stipulated by the conditions of approval modifications to the wing and thrust characteristics of the power plant. This is an area , in which a possible implementation of the required increase in capacity modifications.The obtained results related to the modeling of changes in the geometry of the wing are an integral part of the scheme approval deep modifications in the wing and the power plant is required when creating modifications with enhanced performance.