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Three compounds with diuretic potential were identified from the 95% ethanol extract of

The oleaginous yeast Yarrowia lipolytica is widely used for the production of both bulk and fine chemicals, including organic acids, fatty acid-derived biofuels and chemicals, polyunsaturated fatty acids, single-cell proteins, terpenoids, and other valuable products. Consequently, it is becoming increasingly popular for metabolic engineering applications. Multiple gene manipulation tools including URA blast, Cre/LoxP, and transcription activator-like effector nucleases (TALENs) have been developed for metabolic engineering in Y. lipolytica. However, the low efficiency and time-consuming procedures involved in these methods hamper further research. The emergence of the CRISPR/Cas system offers a potential solution for these problems due to its high efficiency, ease of operation, and time savings, which can significantly accelerate the genomic engineering of Y. lipolytica. In this review, we summarize the research progress on the development of CRISPR/Cas systems for Y. lipolytica, including Cas9 proteins and sgRNA expression strategies, as well as gene knock-out/knock-in and repression/activation applications. Finally, the most promising and tantalizing future prospects in this area are highlighted.

As fungus-like protists, thraustochytrids have been increasingly studied for their faster growth rates and high lipid content. In the 1990s, thraustochytrids were used as docosahexaenoic acid (DHA) producers for the first time. Thraustochytrids genera, such as Thraustochytrium, Schizochytrium, and Aurantiochytrium have been developed and patented as industrial strains for DHA production. The high DHA yield is attributed to its unique and efficient polyketide-like synthase (PKS) pathway. Moreover, thraustochytrids possess a completed mevalonate (MVA) pathway, so it can be used as host for terpenoid production. In order to improve strain performance, the metabolic engineering strategies have been applied to promote or disrupt intracellular metabolic pathways, such as genetic engineering and addition of chemical activators. However, it is difficult to realize industrialization only by improving strain performance. Various operation strategies were developed to enlarge the production quantities from the laboratory-scale, including two-stage cultivation strategies, scale-up technologies and bioreactor design. Moreover, an economical and effective downstream process is also an important consideration for the industrial application of thraustochytrids. Downstream costs accounts for 20-60% of the overall process costs, which represents an attractive target for increasing the cost-competitiveness of thraustochytrids, including how to improve the efficiency of lipid extraction and the further application of biomass residues. This review aims to overview the whole lipid biotechnology of thraustochytrids to provide the background information for researchers.

In recent years, a variety of genetic tools have been developed and applied to various filamentous fungi, which are widely applied in agriculture and the food industry. However, the low efficiency of gene targeting has for many years hampered studies on functional genomics in this important group of microorganisms. The emergence of CRISPR/Cas9 genome-editing technology has sparked a revolution in genetic research due to its high efficiency, versatility, and easy operation and opened the door for the discovery and exploitation of many new natural products. Although the application of the CRISPR/Cas9 system in filamentous fungi is still in its infancy compared to its common use in E. coli, yeasts, and mammals, the deep development of this system will certainly drive the exploitation of fungal diversity. In this review, we summarize the research progress on CRISPR/Cas9 systems in filamentous fungi and finally highlight further prospects in this area.

The overuse of N fertilizer by rice growers triggers excessive greenhouse gas (GHG) emission, leading to the environmental and climatic problem. However, growers will probably suffer loss in profits if they reduce the use of N fertilizer under the existing technology condition. The payment in market-based or government-driven way may overcome the potential barrier. For the appropriate carbon trading market is absent, the government-driven program will play a role in the payment. Three key issues in the designed program are the price of the payment, the participation rate of rice growers, and the variation of items associated with the social welfare. Due to the difficulty in estimating the economic value, prices of the payment can be set according to shadow prices. This paper applies the parametric directional output distance function to derive shadow prices of CO2 for 308 rice growers in Shanghai from 2008&ndash, 2015. Average shadow prices range from RMB 1130 to 3769 yuan/ton (or US 163 to 618 $/ton). Taking the year of 2015 as sample, this paper predicts the participation rate (97.08%) of rice growers with the aim of 10% N fertilizer reduction and the specific price of the payment (7.47 yuan/kg). Moreover, this paper discusses on the variation of factors linked with the social welfare, and derive two important relationships from it. In detail, the relationship between the yield of the rice and the reduction of the N fertilizer should be balanced, the relationship between the improvement on the profit of rice growers (or the participation rate) in the program and the payment by the government should also be balanced.

In recent years, eukaryotic microorganisms have been widely applied to offer many solutions for everyday life and have come to play important roles in agriculture, food, health care, and the fine-chemicals industry. However, the complex genetic background and low homologous recombination efficiency have hampered the implementation of large-scale and high-throughput gene editing in many eukaryotic microorganisms. The low efficiency of homologous recombination (HR) not only makes the modification process labor-intensive but also completely precludes the application of many otherwise very useful genome editing techniques. Thus, increasing the efficiency of HR is clearly an enabling technology for basic research and gene editing in eukaryotic microorganisms. In this review, we summarize the current strategies for enhancing the efficiency of HR in eukaryotic microorganisms (particularly yeasts and filamentous fungi), list some small molecules and candidate genes associated with homologous and non-homologous recombination, and briefly discuss the further development prospects of these strategies.

Microalgae are arguably the most abundant single-celled eukaryotes and are widely distributed in oceans and freshwater lakes. Moreover, microalgae are widely used in biotechnology to produce bioenergy and high-value products such as polyunsaturated fatty acids (PUFAs), bioactive peptides, proteins, antioxidants and so on. In general, genetic editing techniques were adapted to increase the production of microalgal metabolites. The main genome editing tools available today include zinc finger nucleases (ZFNs), transcriptional activator-like effector nucleases (TALENs), and the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas nuclease system. Due to its high genome editing efficiency, the CRISPR/Cas system is emerging as the most important genome editing method. In this review, we summarized the available literature on the application of CRISPR/Cas in microalgal genetic engineering, including transformation methods, strategies for the expression of Cas9 and sgRNA, the CRISPR/Cas9-mediated gene knock-in/knock-out strategies, and CRISPR interference expression modification strategies.

In order to speed up the power grid engineering 3-D design, strengthen project costs management and control, it is urgent to carry out the research on charging standard for power grid engineering 3-D design, providing guidance for power grid engineering 3-D design. Based on the pilot project of power grid engineering 3-D design, design work day calculation model was constructed, forming a 3-D design charging method covering power grid engineering projects’ every stage. In the future, the 3-D design fee can be adjusted reasonably according to 3-D design work maturity, to improve engineering technology and technical management work.

Sophora davidii Franch. is a multipurpose shrub with significant economic and ecological importance in karst mountainous regions of southeastern China. These mountainous ecosystems are associated with altitudinal gradients that can lead to major morphological and genetic differences in the species. We examined the morphological and genetic variation of this species at six sites with different altitudes (600 m–1950 m asl). Significant morphological variations (p

Plant hormones are a class of organic substances which are synthesized during the plant metabolism. They have obvious physiological effect on plant growth at very low concentrations. Generally, plant hormones are mainly divided into 5 categories: auxins, cytokinins, ethylene, gibberellins (GAs) and abscisic acid (ABA). With the deepening of research, some novel plant hormones such as brassinosteroid and salicylates have been found and identified. The plant hormone products are mainly obtained through plant extraction, chemical synthesis as well as microbial fermentation. However, the extremely low yield in plants and relatively complex chemical structure limit the development of the former 2 approaches. Therefore, more attention has been paid into the microbial fermentative production. In this commentary, the developments and technological achievements of the 2 important plant hormones (GAs and ABA) have been discussed. The discovery, producing strains, fermentation technologies, and their accumulation mechanisms are first introduced. Furthermore, progresses in the industrial mass scale production are discussed. Finally, guidelines for future studies for GAs and ABA production are proposed in light of the current progress, challenges and trends in the field. With the widespread use of plant hormones in agriculture, we believe that the microbial production of plant hormones will have a bright future.

Constructing competitive ability evaluation model of electrical equipment enterprise is significance for enterprises to find their own advantages and disadvantages, and adopt differential improvement strategy to improve competitiveness. Evaluation index system of competitive ability of electrical equipment enterprises in china is puts forward creatively in this paper, which covering scale and performance, customer and service, brand and image, strategy and culture, operation and management, innovation and growth these second level indicators, whose index weight were determined by Key Successful Factors method. Through the case study, it is found that SGCC's electrical equipment business is at the leading level in China, but there is still a gap compared with the ABB and SIEMENS such international first-class enterprises.