Objective: Inspired by the principle of bionics, both anionic and cationic peptides with adhesive properties are designed and analyzed the effect of their mixing on adhesion to lay the foundation for the development of new bionic adhesive materials. Methods: The structural characteristics of mussel foot protein 5 (Mfp5) and cement precursor protein of the phragmatopoma californica 3 (Pc3) were analyzed, according to which the anionic and cationic peptides with adhesion properties were designed and screened. The adhesive force and adsorption capacity of these peptides were tested by tensile strength testing machine, atomic force microscope (AFM) and Quartz crystal microbalance (QCM). Furthermore, their underlying adhesion mechanisms were analyzed in terms of their compositions and interactions. Results: The anionic and cationic peptides with the purity of over 95% were synthesized using the solid phase peptide synthesis method. The tensile test showed that the adhesive forces of anionic and cationic peptides increased with the extension of curing time, with the highest value reaching 174.04 kPa and 180.11 kPa, respectively. In addition, the adhesive force of the mixed anionic and cationic peptides was significantly enhanced compared to their own adhesive forces, and the adhesive force of their mixture mixed in equal proportions reached 347.81 kPa. The QCM results showed that the adsorption capacity of cationic peptide, and the mixture of both anionic and cationic peptides on gold (Au) surface reached 82.67 ng/cm2 and 151.53 ng/cm2, respectively. The average microscopic adhesions of anionic and cationic peptides detected by AFM were 5.43 nN and 4.95 nN, respectively, while the average microscopic adhesion of their mixture mixed in equal proportions reached 18.54 nN. Conclusion: The anionic and cationic peptides designed based on mussel and Phragmatopoma californica had certain adhesion properties, which could be significantly increased by electrostatic force mediated complex condensation. Therefore, our study provides a basis for the development of new bionic adhesion materials.
The 2020 edition of the Chinese Pharmacopoeia proposed new quality control standards for recombinant human interferon α-2b, increased the analysis and detection of related proteins and clarified the upper limit of related proteins. However, the related proteins are only slightly different from recombinant human interferon α-2b in structure, and it is difficult to remove them by conventional separation methods. A reversed phase chromatographic purification process of recombinant human interferon α-2b was established in this paper to separate recombinant human interferon α-2b from related proteins. First, the reversed-phase chromatographic packing and the concentration of acetonitrile in the eluent and the loading amount were screened and optimized. Next, the reversed-phase chromatographic separation and purification process of recombinant human interferon α-2b was determined, which include chromatographic packing: HPLCONE-10C18C3 (300 ?, 10 μm); elution conditions: 0.1% TFA-48% acetonitrile aqueous solution equivalent elution; loading amount: no more than 1.6 times of column volume; detection wavelength: 210 nm. Second, the scale up test was carried out. The results showed that the prepared recombinant human interferon α-2b stock solution, with high activity and purity greater than 99%, met the quality control standards of the 2020 edition of the Chinese Pharmacopoeia. The process has the advantages of good separation results, low cost, simple preparation technology and easy commercial production, which provides a valuable reference for the production enterprises of interferons and other biological macromolecular drugs.
11α,17α-dihydroxy progesterone is an important intermediate of steroid hormone drugs and its biosynthesis is mainly produced by microbial transformation of 17α-hydroxyprogesterone. In order to explore the transformation ability of different microorganisms to 17α-hydroxyprogesterone, 11 strains with steroid hydroxylation ability were selected. Through the whole-cell biotransformation experiment, Colletotrichum lini SF-307 with the strongest transformation ability was obtained. Then, the optimal composition of the fermentation medium was determined by a single-factor experiment and orthogonal design. The most suitable fermentation medium was determined: 15 g/L soluble starch, 1.8 g/L ammonium chloride, 0.6 g/L magnesium chloride, and 3 g/L corn pulp. After optimization, the only product 11α, 17α-dihydroxy progesterone was produced by C. lini SF-307. When the substrate was fed at 0.5 g/L with the addition of 1% (V/V) ethanol for co-solubilization, the substrate conversion was 93.2% and the highest concentration was 224.1 mg/L at 56 h, which was increased by 61.1% compared to the original. The results showed that C. lini SF-307 was a new strain of 17α-hydroxyprogesterone hydroxylation. The fermentation optimization can significantly enhance selectivity of 17α-hydroxyprogesterone conversion products and shorten the transformation period. This study is of great significance to the industrial production of 11α,17α-dihydroxy progesterone.
Escherichia coli expression system is widely used as the expression host of recombinant heterologous proteins because of its high expression level, short cycle, low cost and many other advantages. According to statistics, more than 30% of the recombinant protein drugs and 50% of the recombinant proteins were obtained by using E. coli as the expression host. The misfolding or unfolding of proteins and the formation of inclusion bodies are the main obstacles to the wider application of E. coli expression systems. Therefore, it is of great significance to explore the strategy of soluble expression of recombinant proteins in E. coli system. In this paper, the reasons and mechanisms of insoluble expression of recombinant proteins in E. coli expression system and some key factors affecting the solubility of recombinant proteins in E. coli expression system were reviewed. Based on the various steps of expression of foreign proteins in E. coli, the current strategies to promote efficient and soluble expression of proteins in E. coli expression system were summarized, with the aim to provide a reference for further expanding the application of E. coli expression system in the soluble expression of recombinant heterologous proteins.
HIV-1 broadly neutralizing antibodies (HIV-1 bNAbs) are a class of antibodies that can neutralize most of the circulating strains. The study of HIV-1 bNAbs can provide candidates for anti-AIDS drugs and guide vaccine design, and meanwhile HIV-1 bNAbs is an important indicator for evaluating the efficacy of HIV-1 vaccines. HIV-1 bNAbs can be obtained through traditional screening techniques, such as hybridoma technology, Epstein-Barr virus transformation, and the display library technology. In recent years, with the development of single-cell cloning and sorting technologies, the screening efficiency and antibody specificity of HIV-1 bNAbs have significantly improved. Combined screening methods and novel screening technologies, such as LIBRA-seq and bioinformatics-assisted screening techniques, can unify antibody sequences and functional information, providing technical support for HIV-1 bNAb screening and vaccine design. In addition, these screening techniques and methods for HIV-1 can also be used for the screening of bNAbs against other viruses, providing useful insights into vaccine design and antiviral drug development. This article reviews the widely used screening techniques and latest advances in HIV-1 bNAbs, providing a reference for the screening of HIV-1 or other viruses’ bNAbs in the future.
Therapeutic antiviral drugs, neutralizing antibody and preventive vaccines have been proven to be the most effective control measures towards emerging and reemerging viruses with high pathogenicity and infectivity like SARS-CoV-2. However, the experiments involving live viruses must be carried out in biosafety level 3 (BSL-3) or BSL-4 facilities. To facilitate the evaluation of these antiviral products, the pseudovirus system has been developed based on the human immunodeficiency virus (HIV)/vesicular stomatitis virus (VSV) packaging system, as well as expression plasmids carrying envelope proteins to perform the function of attachment and fusion similar to the wild-type virus. Membrane-associated RING-CH (MARCH) E3 ubiquitin ligase proteins have been reported to downregulate the envelope proteins and significantly affect the yield and infection efficiency of pseudoviruses. This review summarizes the current progress in the effect of engineering MARCH-resistant envelop proteins by lysine modification on the production of pseudoviruses. Apparently, increased expression level from the surfaces of packaging cells and improved processing of the envelope protein in the packaging cells will greatly promote the development of antiviral drugs, antibody screening, vaccine research, and receptor recognition.
The rapid development of synthetic biology has promoted the biosynthesis of various complex chemicals in microbial cell factories. However, there are still many problems such as low yield and low production efficiency. Genetically encoded biosensors can sense the fluctuation of intracellular and extracellular metabolite concentration and external environment, and produce measurable signal output or regulate gene expression level in metabolic pathway. Biosensors have aroused widespread attention among synthetic biologists because of their advantages of low cost, simple operation and reproducibility. At present, genetically encoded biosensors have become an important part of synthetic biology and metabolic engineering, and also a powerful tool for metabolic dynamic regulation and ideal phenotype evolution/screening in microbial cell factories. Therefore, the composition and operating principle of genetically encoded biosensors are summarized first, and then, the latest application research of genetically encoded biosensors in dynamic regulation and high-throughput screening of microbial metabolism is emphatically introduced. Finally, the main challenges faced in the design and construction of genetically encoded biosensors are explored, and the future development prospects are discussed.
Saccharomyces cerevisiae is a common strain used in the field of bioethanol production. This paper reviews recent progress of comparative studies on S. cerevisiae genomic sequences in improving the accuracy of gene functional annotation, discovering molecular variation among different strains, providing potential target genes for genetic breeding, as well as revealing interspecific genetic evolution of yeasts, and exploring the correlation between genotypes and phenotypes. Moreover, yeast genetic breeding for bioethanol production to meet the requirements of industrial production was further discussed, and some insightful views on the bioresource mining of the genome of Saccharomyces cerevisiae with the increasing number of genome-sequenced strains, its important value, and research prospects were also provided.
Plant-derived terpenoids exhibit pharmacological activities such as anti-inflammatory and antioxidant effects, and inhibition of tumor cell proliferation, making them widely used in medicine. In recent years, microbial cell factories have gained significant attention for the synthesis of terpenoids. Efficient terpenoid synthesis in microorganisms requires regulation and optimization of metabolic athways. Subcellular compartmentalization is a common regulatory strategy that plays an essential role in constructing microbial cell factories. Subcellular compartmentalization of metabolic pathways enhances the concentration of enzyme and substrate, inhibits the transfer of metabolic flux towards by-products, reduces accumulation of toxic intermediates, and enables efficient terpenoid synthesis. Although the research on the synthesis of terpenoids using compartmentalization has been carried out, there is currently limited information summarizing its application in microbial cell factory construction. Therefore, this review summarizes the physiological characteristics of various organelles and their applications in regulating terpenoid synthesis. It also discusses the development of regulatory strategies, existing problems, and prospects of subcellular compartmentalization, aiming to provide references for the efficient biosynthesis of terpenoids.
Aromatic L-amino acid decarboxylase (AADC)’s role in living organisms is to decarboxylate aromatic L-amino acids into aromatic monoamines, and pyridoxal 5'-phosphate (PLP) is an essential coenzyme for its catalytic function. AADCs transform aromatic L-amino acids to aromatic monoamines, mainly including dopamine, serotonin, tyramine, and tryptamine. These aromatic monoamines are neurotransmitters that maintain normal physiological functions in living organisms and are also important precursors involved in the synthesis of some compounds. Futhermore, they can also be used as active ingredients in drugs to participate in the treatment of many human diseases, with promising applications. As the enzymes necessary for the biosynthesis of aromatic monoamines, AADCs have attracted more researches’ attention, and great progress has also been made in the biosynthesis of aromatic monoamines based on AADCs. Here several major AADCs are reviewed to provide references for better applications of AADCs in the biosynthesis of aromatic monoamines.
Objective: Based on the regional differences in the development of China’s pharmaceutical manufacturing industry, this paper aims to understand and grasp the rules and development trends of the division of labor of the industry by analyzing the regional division of labor in various provinces and regions, and provide decision-making basis and feasible suggestions for constructing a feasible path for high-quality development of China’s biomedical industry. Methods: Based on the available relevant indicators of the pharmaceutical manufacturing industry from 2010 to 2020 and from the perspective of regional economics, we analyzed the regional division of labor and agglomeration of China’s pharmaceutical manufacturing industry using quantitative indicators such as concentration ration and location quotient. Results: From 2010 to 2020, we observed an overall upward trend in industrial concentration in the Beijing-Tianjin-Hebei region, the Yangtze River Delta region, the Guangdong-Hong Kong-Macao Greater Bay Area, and the Chengdu-Chongqing region, showing a high degree of industrial agglomeration. The overall location entropy and scale concentration in the eastern provinces of China showed an increasing trend, with a relatively good performance of regional agglomeration effect. The location entropy showed a relatively stable development and a decreasing trend in the central provinces of China and in the western and northeastern provinces of China, respectively. The pharmaceutical manufacturing industry is expected to become a secondary leading specialized sector in Jiangsu and Shandong provinces in the future, and is an optional leading specialized sector in Beijing, Jiangxi, Hubei, and Sichuan provinces. Conclusion: The pharmaceutical manufacturing industry has become a pillar industry in the economic development of some regions in China. It has showed a gradually emerging trend of industrial agglomeration, and differentiation of the regional division is obvious in the eastern, central, and western regions. It is expected that China’s biopharmaceutical industry chain division and specialized development can be achieved, and its high-quality development can be promoted through strategic planning, top-level design, system supply, and service management at the national level.
Synthetic biology, which involves the design and engineering of microorganisms to make them capable of performing novel functions for scientific research, medicine, industry and other fields, has promoted the development of economy and society. With the rapid development of synthetic biotechnology, highly harmful pathogens existing in nature may become objects to be synthesized. The transformation of known pathogens through biotechnology will have an unpredictable impact on human hosts, which is more dangerous than natural pathogens. These circumstances add to the biosecurity elements that need our attention when we adhere to the overall concept of national security. By reviewing the biosafety risks and key points in the areas of known viral synthetic biology, known bacterial synthetic biology, known viral enabling safety risks, known bacterial enabling safety risks, and unknown pathogen synthetic biology in recent years, and focusing both the international cutting-edge scientific and technological (S&T) achievements and advanced S&T development concepts, some biosafety response strategies and scientific suggestions were put forward, which would provide advisory suggestions for the healthy development of synthetic biology and think tank references for decision-makers of national biosafety policies.
