Unfavorable Growth Research Articles

Flagella disruption in Bacillus subtilis increases amylase production yield

BackgroundBacillus subtilis is a Gram-positive bacterium used as a cell factory for protein production. Over the last decades, the continued optimization of production strains has increased yields of enzymes, such as amylases, and made commercial applications feasible. However, current yields are still significantly lower than the theoretically possible yield based on the available carbon sources. In its natural environment, B. subtilis can respond to unfavorable growth conditions by differentiating into motile cells that use flagella to swim towards available nutrients.ResultsIn this study, we analyze existing transcriptome data from a B. subtilis α-amylase production strain at different time points during a 5-day fermentation. We observe that genes of the fla/che operon, essential for flagella assembly and motility, are differentially expressed over time. To investigate whether expression of the flagella operon affects yield, we performed CRISPR-dCas9 based knockdown of the fla/che operon with sgRNA target against the genes flgE, fliR, and flhG, respectively. The knockdown resulted in inhibition of mobility and a striking 2–threefold increase in α-amylase production yield. Moreover, replacing flgE (required for flagella hook assembly) with an erythromycin resistance gene followed by a transcription terminator increased α-amylase yield by about 30%. Transcript levels of the α-amylase were unaltered in the CRISPR-dCas9 knockdowns as well as the flgE deletion strain, but all manipulations disrupted the ability of cells to swim on agar.ConclusionsWe demonstrate that the disruption of flagella in a B. subtilis α-amylase production strain, either by CRISPR-dCas9-based knockdown of the operon or by replacing flgE with an erythromycin resistance gene followed by a transcription terminator, increases the production of α-amylase in small-scale fermentation.

Robust 3D Copper Foam Functionalized with Gold Nanoparticles as Anode for High-Performance Potassium Metal Batteries.

As a possible anode for the next generation of electrochemical energy storage batteries, potassium metal has attracted a great deal of attention in recent years. However, potassium metal batteries suffer from poor stability and low coulombic efficiency due to unfavorable dendrite growth and severe volume expansion of potassium metal anodes during charge and discharge processes. Here, a strategy is developed to inhibit dendrite growth, reduce volume expansion and improve the stability of the potassium metal anode by using three-dimensional (3D) copper foam chemically loaded with a thin layer of uniform gold particles (Au/Cu) as the anode substrate. As the host of potassium deposition for forming K/Au/Cu foam anode, such a 3D copper foam with large specific surface area can reduce the potassium deposition current density. The gold particles on the Cu foam surface with a good affinity to potassium can reduce the potassium deposition overpotential, provide deposition sites and realize uniform and dense deposition. As a result, a stable cycle of more than 500 cycles is achieved by using such a K/Au/Cu foam anode. A full cell with K/Au/Cu foam anode and Prussian blue cathode delivers much better coulombic efficiency, cycle stability and low-temperature performance when compared to that without gold deposition anode (K/Cu). Both the experimental characterization for material structure/morphology/composition and theoretical DFT calculations are carried out for fundamental understanding of the performance enhancement mechanism. The main advantages of this 3D K/Au/Cu foam are its potassiophilicity and less volume expansion during charge/discharge processes, which can reduce or eliminate the potassium dendrite growth through forming favorable and stable solid electrolyte interface.

Interplay between Solid Tumors and Tumor Microenvironment.

Over the past few decades, basic studies aimed at curing patients with cancer have been constantly evolving. A myriad of mechanistic studies on physiological changes and related factors in tumor growth and metastasis have been reported. Recently, several studies have been considerate to how tumors adapt to unfavorable environments, such as glucose deprivation, oxidative stress, hypoxic conditions, and immune responses. Tumors attempt to adapt to unfavorable environments with genetic or non-genetic changes, the alteration of metabolic signals, or the reconfiguration of their environment through migration to other organs. One of the distinct features in solid tumors is heterogeneity because their environments vary due to the characteristics of colony growth. For this reason, researchers are paying attention to the communication between growing tumors and neighboring environments, including stromal cells, immune cells, fibroblasts, and secreted molecules, such as proteins and RNAs. During cancer survival and progression, tumor cells undergo phenotype and molecular changes collectively referred to as cellular plasticity, which result from microenvironment signals, genetics and epigenetic alterations thereby contributing to tumor heterogeneity and therapy response. In this review, we herein discuss the adaptation process of tumors to adverse environments via communication with neighboring cells for overcoming unfavorable growth conditions. Understanding the physiology of these tumors and their communication with the tumor environment can help to develop promising tumor treatment strategies.

Green 2D simonkolleite/zinc based nanostructures for superior antimicrobial and photocatalytic applications

The problem of organic contamination in water, unfavorable microbial growth on food products and antibiotic resistance against human pathogenic microbes has piqued interest around the world. The goal of this research is to see how effective green 2D Simonkolleite/Zinc based nanostructures (SM-Zn NS) against various human pathogenic (bacterial and fungal strains) and their photo degradation activity. Fine 2D Nanosheets of SM-Zn NS were observed by field emission scanning electron microscopy (FESEM). X-ray diffraction validated the crystalline structure of SM-Zn NS. The disc diffusion method was used to demonstrate the bactericidal effect of SM-Zn NS. On various bacterial strains, including Microcuccus luteus (Ml), Basilus subtilis (Bs), Staph aureus (Ba), Basilus pumilus (Bp), E. coli, Pseudomonas aeruginosa (Pa), Staph epidermidis, and Bordetetella bronchiseptica (Bb), at different concentrations of SM-Zn NS (10 μg/mL, 20 μg/mL) and standard drug (Ciprofloxacin 1 mg/mlL). The antifungal activity of SM-Zn NS was demonstrated using the disc diffusion method. Aspergillus terreus, Aspergillus fumigatus, Aspergillus flavus, and Candida albican were tested using a single concentration of SM-Zn NS 20 μg/mL and the standard drug (Terbisil) 1 mg/ml. The results showed that green SM-Zn NS have significant and higher bactericidal as well as fungicidal effects against various human pathogens. Excess Cl− concentration responsible for formation of new defect energy level due to oxygen vacancies and the formation of the heterojunction between valance band and conduction band increased the photocatalytic properties of SM-Zn NS by reducing band gap which resulted in higher photocatalytic degradation efficiency. According to the findings, green SM-Zn NS can be used effectively in environmental remediation applications, as well as can effectively address the future medical concerns.

Biofilm eradication ability of phage cocktail against Listeria monocytogenes biofilms formed on food contact materials and effect on virulence-related genes and biofilm structure

Listeria monocytogenes is a foodborne pathogen that can form biofilms in food processing facilities even under unfavorable growth environment. This study aimed to evaluate the biofilm eradication ability of Listeria-specific bacteriophage (phage) cocktail (LMPC01+02+03) against L. monocytogenes young (1 day) and mature (3 days) biofilms formed on food contact materials (FCMs: polyethylene, polypropylene, and stainless steel) at 4, 15, and 30 °C. In addition, virulence-related genes and biofilm structure parameters of the phage-treated biofilms were investigated. The biofilm eradication ability of the phage cocktail was evaluated on 96 well and MBEC plate, and the results revealed that a multiplicity-of-infection (MOI) 100 of the phage cocktail exhibited the ability of eradicate biofilms. Using MOI 100, the phage cocktail treatment on the biofilms formed on FCMs for 8 h reduced over 2 log CFU/cm2 of the young biofilms, and approximately 1 log CFU/cm2 of the mature biofilms. In addition, the phage treatment against the biofilms resulted in a significant up-regulation of two genes (flaA and motB), and up/down-regulation or no changes in three genes (hlyA, prfA, and actA). Confocal and scanning electron microscopy images revealed the loss of the biofilm matrix after the phage treatment, and quantitative analysis revealed a reduction in the structural parameters of the biofilm, except the microcolonies at the substratum level, which increased. These results suggested that MOI 100 of the phage cocktail (LMPC01+02+03) was an effective tool for eradicating L. monocytogenes biofilms formed on FCMs, and it is essential to develop a countermeasure to eradicate the biofilm remaining after phage treatment.

Different Treatment Modalities of Maxillary Protraction in Cleft Lip and Palate Patients: A Literature Review

Cleft lip and palate is the most common cranio-facial defect with patients displaying unfavorable growth pattern of the cranio-facial complex. When such a deficiency in growing subjects, is left untreated, can lead to severe functional, aesthetic, breathing and psychological problems. To treat patients with cleft lip and palate, early orthopedic correction is considered to be advantageous. This can be applied through a tooth-anchored protraction facemask, bone-anchored protraction facemask or even the application of direct force via intra-oral inter-maxillary elastics anchored in mini-plates between the maxilla and the mandible.

Exploring South African Pacific oyster mariculture potential through combined Earth observation and bioenergetics modelling

The combined use of satellite-derived environmental data and a dynamic energy budget (DEB) model to determine Pacific oyster growth potential was adapted for the South African marine environment. Study areas consisted of the West Coast (high-chlorophyll, low temperature) and the South Coast (variable chlorophyll, higher temperature) ecoregions. Chlorophyll-a and sea surface temperature products from the Moderate Resolution Imaging Spectroradiometer (MODIS) were used to simulate yearly growth for 18 years. Average growth performance at the end of the culture period was mapped and compared for prominent sectors. Industry-relevant growth indicators, “days to reach commercial weight” and “optimal culture period length” were also established.High growth potential was found in eastern nearshore sectors of the South Coast, particularly Plettenberg Bay, where oysters reached a median total weight (TW) of 271 g within 9 months. Other sectors in the region yielded Large commercial size within 150 days. However, South Coast growth hotspots were found to be highly variable, with transient unfavourable growth conditions leading to low flesh mass relative to TW. Growth potential was favourable in northern sectors of the West Coast, where oysters reached a median TW of up to 148 g in 9 months, Large commercial size within 200 days, and contained high flesh mass relative to TW.Current oyster production sites were not found to be optimal for growth. Higher-growth sites coincide with areas in economic decline or with high levels of poverty. However, due to constraints of applying DEB models over large spatial scales, these results are considered preliminary and await in situ verification, as well as a spatial multi-criteria analysis, before investment and development.

Both entry to and exit from diapause arrest in Caenorhabditis elegans are regulated by a steroid hormone pathway.

ABSTRACTDiapause arrest in animals such as Caenorhabditis elegans is tightly regulated so that animals make appropriate developmental decisions amidst environmental challenges. Fully understanding diapause requires mechanistic insight of both entry and exit from the arrested state. Although a steroid hormone pathway regulates the entry decision into C. elegans dauer diapause, its role in the exit decision is less clear. A complication to understanding steroid hormonal regulation of dauer has been the peculiar fact that steroid hormone mutants such as daf-9 form partial dauers under normal growth conditions. Here, we corroborate previous findings that daf-9 mutants remain capable of forming full dauers under unfavorable growth conditions and establish that the daf-9 partial dauer state is likely a partially exited dauer that has initiated but cannot complete the dauer exit process. We show that the steroid hormone pathway is both necessary for and promotes complete dauer exit, and that the spatiotemporal dynamics of steroid hormone regulation during dauer exit resembles that of dauer entry. Overall, dauer entry and dauer exit are distinct developmental decisions that are both controlled by steroid hormone signaling.

Catch crop mixtures have higher potential for nutrient carry-over than pure stands under changing environments

Winter catch crops are grown to scavenge nutrients over a period of unfavorable growth conditions and to conserve nutrients for subsequent release to the following main crop. Since environmental conditions have a strong impact on the growth and nutrient capture in roots and shoots of individual catch crop species, we anticipated that mixtures will be more durable and efficient in nutrient capture due to compensatory effects among component species. We tested this hypothesis and determined the nitrogen and phosphorus accumulation in the shoots and roots of four catch crop species grown in pure vs. mixed stands at two sites for two or three years. Element concentrations were determined in the root and shoot biomass of each species and used to calculate the nutrient pool fixed in the root or shoot biomass. A qPCR-based technique was applied to quantify the root biomass of individual species based on species-specific DNA sequences. Despite considerable variation across environments, the overall plant biomass of white mustard (Sinapis alba), lacy phacelia (Phacelia tanacetifolia) and bristle oat (Avena strigosa) was similar and higher than that of Egyptian clover (Trifolium alexandrinum). While pure stands varied 6- to 24-fold in shoot biomass depending on environmental conditions, the variation was only ~3-fold for catch crop mixtures, with less pronounced variation in the root biomass. In general, the root biomass was comparable to the shoot biomass in each species. Roots contributed 26–46% of the nitrogen and 36–48% of the phosphorus to the total accumulation of these nutrients in the catch crop biomass, thus emphasizing the importance of plant roots as belowground nutrient pool for potential carry-over of nutrients to the subsequent crop. Although the mixture was mostly dominated by two of the four species, namely mustard and phacelia, it captured similar or even larger amounts of nutrients than the best-performing pure stand under any growth condition. This was the case for shoot- and for root-bound nutrients. Our results indicate that catch crop mixtures have higher durability than pure cultures to environmental variations. The amount of nitrogen captured by the mixture meets the average postharvest nitrogen that is left over by a wide range of cash crops, thus emphasizing that catch crop mixtures represent an efficient nutrient management tool in crop rotations.

Multi-segmented maxillary ortho-surgical treatment in Class II patients with maxillary protrusion and open bite: a concise systematic review

Introduction: Anterior open bite is the lack of vertical contact or negative overbite between the anterior teeth of the upper and lower arches when the posterior teeth are in occlusion. Its etiology is multifactorial, including heredity, oral habits, unfavorable growth patterns, and increased lymphatic tissue along with mouth breathing and functional oral matrices. The characteristics of individuals with anterior open bite include excessive gonial, mandibular, and occlusal plane angles, mandibular small body, and ramus increased lower anterior facial height, decreased upper anterior facial height, retrusive jaw, Class II tendency, divergent cephalometric planes, lingual position, and inadequate lip seal. Objective: To carry out a concise systematic review of multi-segmented maxillary ortho-surgical treatment in class II patients with maxillary protrusion and open bite. Methods: Experimental and clinical studies (case reports, retrospective, prospective and randomized) with qualitative and/or quantitative analysis were included, following the rules of the systematic review-PRISMA. A total of 289 articles were initially found and, after selection, 17 articles were used to compose this study. Results and conclusion: Significant improvement in anterior occlusion can be expected in most patients when maxillary or mandibular surgery is used for Class II open bite correction. However, there will be individual patients in whom there will be considerable post-treatment changes in the anteroposterior and vertical dimensions. Although individual morphology needs to be taken into account, it appears that both short-term and long-term stability are likely to be greater after Le Fort I surgery compared to bilateral sagittal split osteotomy.

How does multiannual plastic mulching in strawberry cultivation influence soil fungi and mycotoxin occurrence in soil?

The production of mycotoxins is often interpreted as fungal response to cope with unfavorable growth conditions induced by toxic substances, environmental and biological factors. Soil covers influence soil environment, which consequently can change the abundance and composition of microbial communities. We investigated how plastic coverage (PC) influence soil fungi and mycotoxin occurrence (deoxynivalenol, nivalenol and zearalenone) compared to the traditional straw coverage (SC) in dependence of soil depth and time in a 3-year field experiment in strawberry cultivation. In total, 300 soil samples, resulting from two treatments, three soil layers, and ten sampling dates (n = 5), were analyzed for mycotoxins and ergosterol (proxy for soil fungal biomass) with liquid chromatography high resolution mass spectrometry and high-performance liquid chromatography with UV-detection, respectively. The modified microclimate under PC had no significant influence on fungal biomass, whereas SC promoted fungal biomass in the topsoil due to C-input. Mycotoxins were detected under both cover types in concentrations between 0.3 and 21.8 µg kg−1, mainly during strawberry establishment period and after fungicide application. Deoxynivalenol had the highest detection frequency with 26.3% (nivalenol: 8.3%, zearalenone: 8.7%). This study confirmed the in situ production of mycotoxins in soil, which seems mainly triggered by field treatment (fungicide application) and plant growth stage (establishment period) rather than on mulching type. Further investigations are necessary to better understand the influence of different agricultural practices and soil types on the production and fate of mycotoxins.

Prelamination of the Radial Forearm Free Flap Using Free Full-Thickness Eyelid Skin Grafts: A New Approach for Intraoral Defect Reconstruction.

Free flap transfer for reconstruction of intraoral defects is a common procedure in oral and maxillofacial surgery. For tumor-related defects, the radial forearm flap is widely used for soft tissue restoration. However, transfer of free skin grafts to the donor site region is often required for wound closure after free flap harvesting, resulting in esthetic disturbances due to shrinkage of the grafted skin, attendant scarring, or mismatches in skin texture or color. Furthermore, free flap transfer may result in hair follicle transfer into the oral cavity, causing unfavorable intraoral hair growth in adult men in particular. Free flap prelamination can help reduce the potential disadvantages of free flaps, in terms of both flap design and size and donor site morbidity. For surgical treatment of oral cancer in middle-aged and elderly patients, eyelid dermatochalasis may present as a comorbidity leading to esthetic impairments or, in cases involving the upper eyelid, even a reduced field of view. In these cases, bilateral blepharoplasty can reduce the excess eyelid skin. The present study is the first to attempt to use excised skin after bilateral blepharoplasty as full-thickness skin grafts for radial forearm free flap prelamination. This approach combined surgical therapy of eyelid dermatochalasis with free flap prelamination, thereby avoiding the need to harvest free skin grafts from other anatomically healthy regions to close the donor site defect and preventing the accompanying disadvantages. The reconstruction results and clinical outcomes of patients revealed that radial forearm free flap prelamination using bilateral free full-thickness eyelid skin grafts was an easy and feasible method for intraoral defect reconstruction. In particular, this approach could avoid intraoral hair growth and additional skin grafting from other healthy anatomical regions, yielding good esthetic and functional results at the flap's recipient and donor sites.

Pressureless sintering of HfB2-based ceramics as control rod materials: Synergistic effects of the sintering additive and solid solution

The effects of sintering additives (Boron and SiC) and solid solution (TiB2) on the densification of HfB2-based ceramics, processed by pressureless sintering, were investigated for potential applications as advanced control rod materials. The addition of B was found to improve the densification properties of HfB2 through removal of the oxygen contamination yet incurred unfavourable grain growth. SiC was able to further enhance the densification through a grain pinning effort, improving the microstructure. In combination with oxygen impurity removal by the addition of B, the solid solution of Ti into HfB2 contributed to further improving the densification by reducing the particle size of HfB2 powder, further promoting diffusion during sintering. The grain size of SiC phase was also reduced through the refinement of HfB2 powder via solid solution. The deployment of B and SiC sintering additives, alongside TiB2 solid solution, during pressureless sintering was found to be beneficial in the preparation of high density HfB2-based ceramics, increasing microstructure density and enhancing mechanical properties.

The regional growth and unemployment effects of Engineering & Technology and Economics education in Poland

Using annual time series for the period 2000-2019, this article analyses educational effects of the Engineering & Technology and Economics fields of study for Poland. It was found that the long-term education effects (in levels) are in favour of the former, both in terms of regional output growth and reduction in the number of unemployed. The short-term effects (in the first indicated differences) on both regional growth and unemployment are negative, regardless of the field of study. As both fields of study have unfavourable growth effects in the first differences, it indicates insufficient quality of investments in the human capital.

Polysaccharide Hydrogels for the Protection of Dairy-Related Microorganisms in Adverse Environmental Conditions.

Adverse environmental conditions are severely limiting the use of microorganisms in food systems, such as probiotic delivery, where low pH causes a rapid decrease in the survival of ingested bacteria, and mixed-culture fermentation, where stepwise changes and/or metabolites of individual microbial groups can hinder overall growth and production. In our study, model probiotic lactic acid bacteria (L. plantarum ATCC 8014, L. rhamnosus GG) and yeasts native to dairy mixed cultures (K. marxianus ZIM 1868) were entrapped in an optimized (cell, alginate and hardening solution concentration, electrostatic working parameters) Ca-alginate system. Encapsulated cultures were examined for short-term survival in the absence of nutrients (lactic acid bacteria) and long-term performance in acidified conditions (yeasts). In particular, the use of encapsulated yeasts in these conditions has not been previously examined. Electrostatic manufacturing allowed for the preparation of well-defined alginate microbeads (180–260 µm diameter), high cell-entrapment (95%) and viability (90%), and uniform distribution of the encapsulated cells throughout the hydrogel matrix. The entrapped L. plantarum maintained improved viabilities during 180 min at pH 2.0 (19% higher when compared to the free culture), whereas, L. rhamnosus appeared to be less robust. The encapsulated K. marxianus exhibited double product yields in lactose- and lactic acid-modified MRS growth media (compared to an unfavorable growth environment for freely suspended cells). Even within a conventional encapsulation system, the pH responsive features of alginate provided superior protection and production of encapsulated yeasts, allowing several applications in lacto-fermented or acidified growth environments, further options for process optimization, and novel carrier design strategies based on inhibitor charge expulsion.

Morphological and Anatomical Profile of Cassia occidentalis (L.) Species Grown in the Republic of Moldova

Abstract The current research deals with the morpho-anatomical characteristics of Cassia occidentalis (L.) (Coffee senna plant), grown in the steppe climate conditions of the Republic of Moldova. This study was performed according to investigated organ in vegetative periods of 2019-2021 years. Morphological and anatomical indices of organs with diagnostic role in identifying species and those with adaptive potential to the action of unfavorable growth factors, have been elucidated. These indices were evaluated in the light of data already reported by other researchers. This morpho-anatomical research has revealed new aspects to support some anatomical features already outlined, but less confirmed in the studies of the last decades and will serve as landmarks for a real clarity of the integral microstructural picture of the C. occidentalis species.

ATP-binding cassette transporters in nonmodel plants.

Knowledge about plant ATP-binding cassette (ABC) proteins is of great value for sustainable agriculture, economic yield, and the generation of high-quality products, especially under unfavorable growth conditions. We have learned much about ABC proteins in model organisms, notably Arabidopsis thaliana; however, the importance of research dedicated to these transporters extends far beyond Arabidopsis biology. Recent progress in genomic and transcriptomic approaches for nonmodel and noncanonical model plants allows us to look at ABC transporters from a wider perspective and consider chemodiversity and functionally driven adaptation as distinctive mechanisms during their evolution. Here, by considering several representatives from agriculturally important families and recent progress in functional characterization of nonArabidopsis ABC proteins, we aim to bring attention to understanding the evolutionary background, distribution among lineages and possible mechanisms underlying the adaptation of this versatile transport system for plant needs. Increasing the knowledge of ABC proteins in nonmodel plants will facilitate breeding and development of new varieties based on, for example, genetic variations of endogenous genes and/or genome editing, representing an alternative to transgenic approaches.

Effects of Prednisolone Derivative and Panaxydol: Biosurfactants on Cell Wall Integrity of Acne-Causing Resistant Bacteria.

Acne is one of the most common dermatological skin problem caused due to inflammation of the skin, leading to unfavorable growth of Propionibacterium acnes. It is a slow growing anaerobic, gram-positive bacterium that releases chemotactic factors and leads to the complex pathogenicity of acne. There are several acne treatments/therapies available, but topical therapy is usually the first choice for mild to moderate acne, and as the severity of the acne increases, the treatment modalities fail. There are many acne treatment options available, but topical therapy is best suited for mild - to - moderate skin problems, and then as the seriousness of the acne grows, the therapeutic approaches fall short. Biosurfactants are surfactants produced from plants or animals; Saponins are plant derived non-ionic biosurfactants which have steroidal and triterpenic glycosides distributed largely in plant kingdom. Numerous studies conducted by scientists have established the antimicrobial activity of and are considered more advantageous over synthetic precursors as they are eco-friendly, cheap and non-toxic. The present study was undertaken to investigate the antibacterial activity of saponins (bio-surfactants) characterized using mass spectroscopy against acne-causing bacteria. The discharge of cellular components including protein and UV-sensitive materials in the cell-free supernatant was provoked by saponin, confirming the cellular and membrane disturbances.. Furthermore, various morphological changes on the bacterial cell surface structure by Transmission electron microscopy and scanning electron microscopy revealed the disruption of the cell integrity leading to death. Results confirmed presence of non-ionic surfactants primarily affecting the disruption and destruction to the bacteria which indicates that saponins are efficient components with great potential applications in various pharmaceutical preparations. Effects of Prednisolone derivative and Panaxydol: Biosurfactants on cell wall integrity of Acne-Causing Resistant Bacteria.

Atomic-scale regulation of anionic and cationic migration in alkali metal batteries

The regulation of anions and cations at the atomic scale is of great significance in membrane-based separation technologies. Ionic transport regulation techniques could also play a crucial role in developing high-performance alkali metal batteries such as alkali metal-sulfur and alkali metal-selenium batteries, which suffer from the non-uniform transport of alkali metal ions (e.g., Li+ or Na+) and detrimental shuttling effect of polysulfide/polyselenide anions. These drawbacks could cause unfavourable growth of alkali metal depositions at the metal electrode and irreversible consumption of cathode active materials, leading to capacity decay and short cycling life. Herein, we propose the use of a polypropylene separator coated with negatively charged Ti0.87O2 nanosheets with Ti atomic vacancies to tackle these issues. In particular, we demonstrate that the electrostatic interactions between the negatively charged Ti0.87O2 nanosheets and polysulfide/polyselenide anions reduce the shuttling effect. Moreover, the Ti0.87O2-coated separator regulates the migration of alkali ions ensuring a homogeneous ion flux and the Ti vacancies, acting as sub-nanometric pores, promote fast alkali-ion diffusion.

Cloning of Acetoacetyl-CoA reductase and Polyhydroxybutyrate synthase genes from the local isolate Bacillus aryabhattai 6N-NRC into Escherichia coli

Polyhydroxybutyrate (PHB) is the most known degradable biopolymer, produced by some genera of bacteria under unfavorable growth conditions. Isolation and cloning of acetoacetyl-CoA reductase (phbB) and polyhydroxybutyrate synthase (phbC) genes from local isolate previously identified as Bacillus aryabhattai 6N-NRC (GenBank accession no. MH997667.1) was achieved. Suitable primers designed for the phbB and phbC PCR approach were used to clone the phbB and phbC genes. The phbB and phbC genes were successfully isolated, cloned and the PCR amplicon 744 bp and 1089 bp corresponding to phbB and phbC genes were identified, cloned with the pET-29a (+) carrying the phbB and phbC genes, transformed and expressed in Escherichia coli BL21. The amplification of the phbB and phbC genes using specific primers of pET-29a (+) plasmid was performed. The open reading frame of phbB sequence was found to be 99.06% identical to the sequence of acetoacetyl-CoA reductase of B. aryabhattai (GenBank accession no. CP024035.1), while the open reading frame of phbC sequence was found to be 87.18% identical to the sequence of polyhydroxybutyrate synthase of B. aryabhattai (Gen Bank accession no. CP024035.1) after DNA sequencing. The analysis of the recombinant proteins from E. coli BL21 recombinant colony by tricine-polyacrylamide gel electrophoresis clarified that the expressed phbB and phbC genes in E. coli BL21 strain showed distinct bands of intensity 26.3 KD and 37.5 KD, respectively.