Syngas Fermentation for the Production of Bio-Based Polymers: A Review

Increasing environmental awareness among the general public and legislators has driven this modern era to seek alternatives to fossil-derived products such as fuel and plastics. Addressing environmental issues through bio-based products driven from microbial fermentation of synthetic gas (syngas) could be a future endeavor, as this could result in both fuel and plastic in the form of bioethanol and polyhydroxyalkanoates (PHA). Abundant availability in the form of cellulosic, lignocellulosic, and other organic and inorganic wastes presents syngas catalysis as an interesting topic for commercialization. Fascination with syngas fermentation is trending, as it addresses the limitations of conventional technologies like direct biochemical conversion and Fischer–Tropsch’s method for the utilization of lignocellulosic biomass. A plethora of microbial strains is available for syngas fermentation and PHA production, which could be exploited either in an axenic form or in a mixed culture. These microbes constitute diverse biochemical pathways supported by the activity of hydrogenase and carbon monoxide dehydrogenase (CODH), thus resulting in product diversity. There are always possibilities of enzymatic regulation and/or gene tailoring to enhance the process’s effectiveness. PHA productivity drags the techno-economical perspective of syngas fermentation, and this is further influenced by syngas impurities, gas–liquid mass transfer (GLMT), substrate or product inhibition, downstream processing, etc. Product variation and valorization could improve the economical perspective and positively impact commercial sustainability. Moreover, choices of single-stage or multi-stage fermentation processes upon product specification followed by microbial selection could be perceptively optimized.

Enzymatic Regulation of Drought and Heat Stresses in Maize (Zea mays L.)

Unfavorable environmental conditions, whether towards increase or decrease direction, are a general feature of our planet ecosystem. Stress conditions fall into two categories, biotic including insects and diseases and abiotic including drought, salts, temperature, etc. Drought is described the most limiting factor that determine crop productivity, and under certain condition drought damages cannot be avoided. Plant have evolved a wide range of mechanisms to cope with extreme environmental conditions. However, most of these strategies depend partially or completely on antioxidant defense system through which plants can control the cell content of reactive oxygen and nitrogen species (ROS and RNS). There should be more attention to climate change, not only by developing tolerant species, but also to natural disasters that can be devastating, as happening nowadays.

Regulation of Dynamic Protein S-Acylation

Protein S-acylation is the reversible addition of fatty acids to the cysteine residues of target proteins. It regulates multiple aspects of protein function, including the localization to membranes, intracellular trafficking, protein interactions, protein stability, and protein conformation. This process is regulated by palmitoyl acyltransferases that have the conserved amino acid sequence DHHC at their active site. Although they have conserved catalytic cores, DHHC enzymes vary in their protein substrate selection, lipid substrate preference, and regulatory mechanisms. Alterations in DHHC enzyme function are associated with many human diseases, including cancers and neurological conditions. The removal of fatty acids from acylated cysteine residues is catalyzed by acyl protein thioesterases. Notably, S-acylation is now known to be a highly dynamic process, and plays crucial roles in signaling transduction in various cell types. In this review, we will explore the recent findings on protein S-acylation, the enzymatic regulation of this process, and discuss examples of dynamic S-acylation.

Compatibility of Beauveria bassiana and a Plant Secondary Metabolite: A Novel Modeling Approach to Invade Host Defense for Effective Control of Oligonychus afrasiaticus (McGregor) on Date Palms

Oligonychus afrasiaticus (McGregor) is an important pest causing substantial economic losses to date palm fruits (dates). The application of mycopathogens with plant secondary metabolites, which may proceed synergistically is thus essential to augment sustainable management strategy for O. afrasiaticus. In this regard, extensive laboratory experimentation involving compatibility, synergism, and host defense was performed to develop stable pest management option. The toxin-pathogen compatibility assay results revealed compatible interaction (biological index = 79–95) of B. bassiana ARSEF 8465 against each tested concentration of commercially available (+)-α-Pinene that provide the opportunity to further explore the time and concentration dependent mortality and defense related enzymatic regulation analysis. The time-mortality response assays that mainly comprised of various proportions of B. bassiana ARSEF 8465 and (+)-α-Pinene revealed that the sole application of B. bassiana ARSEF 8465 (LC50 = 19.16 mg/mL), and (+)-α-Pinene (3.41 mg/mL) found to be least lethal compared with joint applications (LC50 ranged from 1.32–7.06 mg/mL). The treatments complied under Scheme IV (80% (+)-α-Pinene: 20% B. bassiana ARSEF 8465 Conidia) led to strong synergistic interaction (joint toxicity = 755). In addition, synergistic interactions greatly induced enzymatic activities of the studied antioxidants (CAT and SOD), and defense-related enzymes (GST and AchE). We concluded that join application of B. bassiana ARSEF 8465 and (+)-α-Pinene is a promising option for controlling Oligonychus afrasiaticus populations.

Quality Control of Colostrum and Protein Calf Milk Replacers

Introduction. Improving technologies and providing young farm animals with high-quality feed are the primary tasks for successful reproduction and maintenance of dairy cattle. The research objective was to assess the quality characteristics of colostrum and milk replacers, as well as their technological prospects. Study objects and methods. The research featured colostrum, calf milk replacers (CMR), processing methods, and quality characteristics. The paper introduces an analysis of various sustainable processes of obtaining new CMRs. Results and discussion. The article describes colostrum: recommended intake for young calves, qualitative characteristics, and control methods. It focuses mostly on the microbiological characteristics of colostrum, as well as on its role in developing the immune system of calves and the prospects of enzymatic regulation of its functional properties. Enzymatic regulation is based on deep proteins hydrolysates and a highly active serine protease (alcalase). The authors studied variants of using various enzyme preparations and bacterial starter cultures for obtaining hydrolyzed and fermented colostrum, analyzed the main process indicators of milk replacers with intermediate moisture content, and tested various methods for assessing the fatty acid and protein composition of concentrated milk replacers. Production methods proved to have a significant impact on the indicators in question. Conclusion. Reproduction of the dairy herd genetic potential depends on the diet of the young farm animals, and so does the economy of agricultural production. Enzymatic processing of raw materials proved to be the most promising approach for obtaining products with improved functional properties. Deep colostrum hydrolysates can also be an important part of functional foods for children, athletes, in dietary foods, etc.

γ-Secretase Modulatory Proteins: The Guiding Hand Behind the Running Scissors

Described as the “proteasome of the membrane” or the “scissors in the membrane,” γ-secretase has notoriously complicated biology, and even after decades of research, the full extent of its regulatory mechanism remains unclear. γ-Secretase is an intramembrane aspartyl protease complex composed of four obligatory subunits: Nicastrin (NCT), Presenilin (PS), Presenilin Enhancer-2 (Pen-2), and Anterior pharynx-defective-1 (Aph-1). γ-Secretase cleaves numerous type 1 transmembrane substrates, with no apparent homology, and plays major roles in broad biological pathways such as development, neurogenesis, and cancer. Notch and the amyloid precursor protein (APP) and are undoubtedly the best-studied γ-secretase substrates because of their role in cancer and Alzheimer’s disease (AD) and therefore became the focus of increasing studies as an attractive therapeutic target. The regulation of γ-secretase is intricate and involves the function of multiple cellular entities. Recently, γ-secretase modulatory proteins (GSMPs), which are non-essential subunits and yet modulate γ-secretase activity and specificity, have emerged as an important component in guiding γ-secretase. GSMPs are responsive to cellular and environmental changes and therefore, provide another layer of regulation of γ-secretase. This type of enzymatic regulation allows for a rapid and fine-tuning of γ-secretase activity when appropriate signals appear enabling a temporal level of regulation. In this review article, we discuss the latest developments on GSMPs and implications on the development of effective therapeutics for γ-secretase-associated diseases such as AD and cancer.

The DEAD-box RNA helicase Ded1 from yeast is associated with the signal recognition particle (SRP), and its enzymatic activity is regulated by SRP21

ABSTRACTThe DEAD-box RNA helicase Ded1 is an essential yeast protein involved in translation initiation. It belongs to the DDX3 subfamily of proteins implicated in developmental and cell-cycle regulation. In vitro, the purified Ded1 protein is an ATP-dependent RNA binding protein and an RNA-dependent ATPase, but it lacks RNA substrate specificity and enzymatic regulation. Here we demonstrate by yeast genetics, in situ localization and in vitro biochemical approaches that Ded1 is associated with, and regulated by, the signal recognition particle (SRP), which is a universally conserved ribonucleoprotein complex required for the co-translational translocation of polypeptides into the endoplasmic reticulum lumen and membrane. Ded1 is physically associated with SRP components in vivo and in vitro. Ded1 is genetically linked with SRP proteins. Finally, the enzymatic activity of Ded1 is inhibited by SRP21 with SCR1 RNA. We propose a model where Ded1 actively participates in the translocation of proteins during translation. Our results open a new comprehension of the cellular role of Ded1 during translation.