Mevalonate, an important intermediate product of the mevalonate pathway, has a broad spectrum of applications. With the rapid growth of metabolic engineering and synthetic biology, mevalonate biosynthesis by microorganisms is feasible and holds great promise in the future. In this review, we summarize the applications of mevalonate and its derivatives and describe the biosynthesis pathways of mevalonate. The current status of mevalonate biosynthesis is also detailed with an emphasis on metabolic engineering strategies to enhance mevalonate production in typical industrial organisms, including Escherichia coli, Saccharomyces cerevisiae, and Pseudomonas putida, suggesting new insights for the efficient production of biosynthesized mevalonate.

The current new technology in the automotive sector depends on the primary energy source because the power source is from the secondary energy source. Besides, the interest in biofuels is increasing due to the weaknesses of fossil fuels that have been voiced for years. The feedstock is important in biodiesel production and its use in the engine. Mustard oil is non-edible, high mono-unsaturated fatty acid value, conveniences in cultivation conditions, and worldwide use that offer significant advantages to biodiesel producers. The presence of erucic acid, which forms the basis of mustard biodiesel, makes itself felt in the prevention of the fuel-food debate, its effect on biodiesel fuel properties, and its relationship to engine performance and exhaust emissions. Along with the minuses of mustard biodiesel in kinematic viscosity and oxidation ability, the problems experienced in engine performance and exhaust emissions compared to diesel fuel offer new studies to policymakers, industrialists and researchers. Accordingly, this review focuses on the recent finding in fuel properties, engine performance and emission characteristic of mustard seed biodiesel as well as its types, geographical distribution, and biodiesel production. It can be stated that this study will be an important supplementary reference to the above-mentioned groups.

The issue of environmental pollution has been worsened by the emergence of new contaminants whose morphology is yet to be fully understood . Several techniques have been adopted to mitigate the pollution effects of these emerging contaminants, and bioremediation involving plants, microbes, or enzymes has stood out as a cost-effective and eco-friendly approach. Enzyme-mediated bioremediation is a very promising technology as it exhibits better pollutant degradation activity and generates less waste. However, this technology is subject to challenges like temperature, pH, and storage stability, in addition to recycling difficulty as it is arduous to isolate them from the reaction media. To address these challenges, the immobilization of enzymes has been successfully applied to ameliorate the activity, stability, and reusability of enzymes. Although this has significantly increased the uses of enzymes over a wide range of environmental conditions and facilitated the use of smaller bioreactors thereby saving cost, it still comes with additional costs for carriers and immobilization. Additionally, the existing immobilization methods have their individual limitations. This review provides state-of-the-art information to readers focusing on bioremediation using enzymes. Different parameters such as: the sustainability of biocatalysts, the ecotoxicological evaluation of transformation contaminants, and enzyme groups used were reviewed. The efficacy of free and immobilized enzymes, materials and methods for immobilization, bioreactors used, challenges to large-scale implementation, and future research needs were thoroughly discussed.

Shellfish are a leading cause of allergies worldwide, affecting about one-tenth of the general population. The sarcoplasmic calcium-binding protein, also known as allergen Pen m 4, is an important factor in shrimp allergies. Our objective was to assess the most effective techniques for producing a recombinant Pen m 4 protein as a potential tool for diagnosing shrimp allergies. In this study, for the first time, we produced a functional recombinant Pen m 4 protein in a eukaryotic system, Pichia pastoris, and analyzed it against Escherichia coli-produced equivalents in enzyme-linked immunosorbent and reverse-phase protein microarray assays. A dual tag system based on the maltose-binding protein was successfully used to increase the yield of Pen m 4 by 1.3-2.3-fold in both bacteria and yeast, respectively. Immunological characterization showed that N-glycosylation is neither crucial for the folding of Pen m 4 nor its recognition by specific IgE. However, the Ca2+-depletion assay indicated a dependence on calcium ion presence in blood samples. Results demonstrate how a comparative analysis can elucidate essential allergen manufacturing points. In conclusion, E. coli-produced Pen m 4 protein fused with the maltose-binding protein should be the preferred option for further studies in Penaeus monodon allergy diagnostics.

Chinese Hamster Ovary cells have been widely used as host cells for production of recombinant therapeutic molecules. Cell line development is a decisive step, which must be carried out with an efficient process. In particular, degree of selection stringency is an important parameter for identification of rare, high-producing cell lines. In the CHOZN® CHO K1 platform, selection of top-producing clones is based on puromycin resistance, whose expression is driven by Simian Virus 40 Early (SV40E) promoter. In this study, novel promoters have been identified to drive expression of selection marker. Decrease of transcriptional activity compared to SV40E promoter was confirmed by RT-qPCR. Selection stringency was increased, as seen by decreased surviving rate of transfected mini-pools and longer recovery duration of transfected bulk pools. Several promoters led to a 1.5-fold increase of maximum titer and a 1.3-fold increase of mean specific productivity of the monoclonal antibody over the clone generation. Expression level was maintained stable over long term cultivation. Finally, productivity increase was confirmed on several monoclonal antibodies and fusion proteins. Lowering the strength of promoter for expression of selective pressure resistance is an efficient strategy to increase selection stringency, which can be applied on industrial CHO-based cell line development platforms.

Soil salinity interferes with plant growth and development. Bacillus genus has been used to increase the growth and productivity of a wide variety of crops by alleviating the effects of salt stress. A total of thirty two Bacillus isolates were obtained from maize rhizosphere, and their plant growth-promoting (PGP) traits and biocontrol activities were tested. Bacillus isolates displayed varying degrees of PGP properties-the production of extracellular enzymes, indole acetic acid, hydrogen cyanide, phosphate solubilization, biofilm formation, and antifungal potential against several fungal pathogens. The phosphate-solubilizing isolates belong to B. safensis, B. thuringiensis, B. cereus, and B. megaterium species. Each Bacillus isolate demonstrated different levels of antifungal activity against the fungal pathogens tested. Biofilm production by some salt-tolerant isolates significantly increased at elevated levels of NaCl (p < 0.05). The strains B. safensis B24, B. halotolerans B7/B18, B. subtilis B26, and B. thuringiensis B10 significantly increased the length of root (by 32.7-38.2%) and shoot (by 19.5-29.8%) of maize (p < 0.05). Maize plants treated with some Bacillus strains displayed significantly greater chlorophyll content with an increase of 26.7-32.1% (p < 0.05). Among PGP properties, enhanced biofilm formation played a more important role in maize growth under higher salinity. These salt-tolerant biofilm-forming strains could be efficiently used as bio-inoculant for maize under salinity stress.