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Asymmetric reductive amination is one of the most important reactions in the preparation of chiral amine pharmaceutical intermediates. Different kinds of enzymes have been applied to the synthesis of chiral amines Among them, the development of reductive amination reactions catalyzed by NAD(P)H-dependent oxidoreductases is attractive, as it would permit a one-step transformation of prochiral ketones into chiral amines with high optical purity. In this review, the recent advances in enzyme structure, catalytic mechanism, protein engineering and the application in reductive amination reactions of NAD(P)H-dependent oxidoreductases, including imine reductase, amino acid dehydrogenase, opine dehydrogenase and reductive aminase, are summarized.Epigenetic nucleoside modifications are critical for the stability and translational efficiency of messenger RNA. Depending on the organism, developmental stage, and tissue/organ investigated, the location and abundance of these nucleoside modifications may differ, which in turn influence the splicing event, half-life time of mature mRNA, as well as translation efficiency. Among the approximately 170 RNA nucleoside modifications, only a handful are found in mRNAs. The low abundance and high organ specificity make it a challenging work to study the role of each specific mRNA nucleoside modification. However, with the technical advances in recent years, including meRIP, great progress has been achieved, especially on the function of m⁶A and m⁵C epigenetic markers in eukaryotes. This review summarizes recent progress on nucleoside modifications of messenger RNAs, on their distribution on transcripts and their role in regulating growth anddevelopment. We also discuss the technical bottleneck and key issues for future investigation.Natural silks, produced by spiders and silkworms, are excellent materials with marvelous mechanical properties, biocompatibility and biodegradability, and widely used in the fields of textile, optics, electronics, biomedicine and environmental engineering. So far, there are many spinning methods to improve the mechanical properties of artificial fibers, such as wet spinning, dry spinning, and electrospinning. However, the performance of most artificial fibers is still inferior to natural silks. It is important to understand the correlations between hierarchical structures and performance in the field of artificial spinning. This review introduces the formation of natural silks, the relationship between the mechanical properties of silks and the hierarchical structure, the research progress in artificial spinning, and the application of silks.As an ancient and huge family of membrane proteins, ATP-binding cassette transporter (ABC transporter) plays an important physiological role in most organisms. https://www.selleckchem.com/products/bms-927711.html Herein, we introduce the research progress in ABC transporters on the aspects of structural characteristic, transport mechanism and physiological functions. We also focus on the application of ABC transporters in the field of synthetic biology in recent years. Finally, we propose future research needs.Mycoplasma hyopneumoniae is the pathogen of porcine enzootic pneumonia (PEP). Due to difficulties in studying the pathogenesis of M. hyopneumoniae for blockage on the establishment of gene operation platform and immature animal model, mycoplasmologists still make progress in understanding the interaction between M. hyopneumoniae and host. In this paper, we review the adhesion and damage of M. hyopneumoniae to host cells, the inflammatory response and immune response of host stimulated by M. hyopneumoniae. Meanwhile, we propose research directions of the pathogenesis of M. hyopneumoniae in the future. This review can provide references for the follow-up study on the interaction between M. hyopneumoniae and host, and provide theoretical basis for effective vaccine and drug development.Exosomes are a class of small extracellular vesicles. The lipid double-layer membrane envelops bioactive molecules including proteins and nucleic acids, which is transported throughout the body through the body fluid. Previous studies have indicated that exosomes play significant roles in viral infection. Viruses need to complete the life cycle in the host cells and release nascent virions, which partially coincides with the production and secretion of exosomes. On one hand, viruses hijack exosomes, and load their components into exosomes to escape from the host immune response and promote the replication. On the other hand, the host seizes exosomes to deliver antiviral factors to resist viral infection. The purpose of this review is to provide new insights into relevant research by discussing the roles of exosomes in viral infection from the perspective of both viruses and hosts.In order to achieve better tumor treatment, researchers have designed dual and multiple responsive smart nanocarriers in the tumor microenvironment. Among them, the research based on acid-sensitive dual-responsive nanocarriers is the most extensive and common one. Intelligent nanocarriers have initially achieved long circulation in body, effective accumulation in tumor cells, and controlled drug release in tumor microenvironment, with increased anti-tumor effect of drug and reduced damage to normal tissues. However, there are still many problems to be solved in current research, such as high price, complicated nanocarriers structure, and unclear mechanisms of drug delivery in the body, all hampering nanocarriers from clinical applications. This article introduces the progress of nanocarriers in recent years from the dual responsive aspects including acid-temperature, acid-magnetism, acid-redox, acid-enzyme, acid-light and acid-ultrasound, to provide reference for further clinical application of nanomedicine.The incidence of heart failure (HF) increases significantly as people age. HF remains a major concern in public health. Although remarkable achievements have been made to treat heart failure in recent years, the survival rate of patients is still very low and the prognosis is poor. The mortality rate within 5 years after the diagnosis of heart failure is up to 50%. If we can quickly and effectively diagnose heart failure and reasonably stratify according to the risk, it will provide a solid foundation for clinicians to formulate treatment plans. Biomarkers play an important role in the diagnosis, curative effect evaluation and prognosis of heart failure. Heart failure is a complex disease in which various pathophysiological processes are involved over time. When heart failure occurs, neuroendocrine system is activated. With the increase of blood volume and ventricular wall pressure, ventricular myocytes secrete NT-proBNP/BNP. Therefore, NT-proBNP/BNP can be used as a biomarker for diagnosis and prognosis of heart failure.