蛋白酶及其抑制剂关键活性位点研究进展

蛋白酶广泛存在于生物体中,参与分解蛋白质,维持生物体正常的生命活动。蛋白酶抑制剂通过与蛋白酶活性位点结合调控靶蛋白酶活性,从而影响蛋白质代谢。蛋白酶及其抑制剂关键氨基酸的突变,可以影响其生理功能、稳定性、催化活性、抑制特异性等。通过挖掘自然界蛋白酶及其抑制剂的各种突变体,分析它们的关键活性位点,并运用蛋白质工程手段改造和设计活性更强、稳定性更高、特异性更好、环境更友好、成本更低的蛋白酶及其抑制剂,已成为当前的热点研究之一。文中对近年来蛋白酶及其抑制剂关键活性位点研究进行了简要综述,以期深化人们对蛋白酶及其抑制剂活性作用机制的认识,并为蛋白酶及其抑制剂的生物学活性改造研究提供理论参考。     

Anatomy of a hypersensitive site

The 600-bp accessible region at the activated PHO5 promoter in S. cerevisiae has become a paradigm for hypersensitive sites. In this review, we summarize the various experimental strategies used to characterize chromatin at the active promoter and point out their virtues and their limitations. We describe the properties of chromatin at the active PHO5 promoter and what we currently know about the transition from the inactive to the active state. The implications for generating a hypersensitive region in chromatin are discussed.     

Chemical Constituents and Biological Activities of Piper as Anticancer Agents: A Review

Cancer has become the primary cause of death worldwide, and anticancer drugs are used to combat this disease. Synthesis of anticancer drugs has limited success due to adverse side effects has made compounds from natural products with minimal toxicity gain much popularity. Piper species are known to have a biological effect on human health. The biological activity is due to Piper species rich with active secondary metabolites that can combat most diseases, including cancer. This review will discuss the phytochemistry of Piper species and their anticancer activity. The identification and characterization of ten active metabolites isolated from Piper species were discussed in detail and their anticancer mechanism. These metabolites were mainly found could inhibit anticancer through caspase and P38/JNK pathways. The findings discussed in this review support the therapeutic potential of Piper species against cancer due to their rich source of active metabolites with demonstrated anticancer activity.     

中国昆虫资源研究开发现状

昆虫具有种类多、数量大等特点,是一类非常丰富的可再生资源,昆虫体内含有丰富的蛋白质、油脂和人体所需要的游离氨基酸以及一些具有药用价值的活性物质,因此具有较高的开发和利用价值。此文综述了近几年对昆虫资源的研究以及开发利用现状。     

植物提取物及其活性成分抑制细菌生物被膜的研究进展北大核心CSCD

大量研究报道生物被膜细菌对抗生素的耐药性是浮游菌的10–1 000倍,据报道细菌生物被膜是80%以上细菌感染的罪魁祸首,对医疗保健领域构成了严峻的挑战。植物提取物及其活性成分对细菌生物被膜有明显的抑制作用,包括减少生物被膜量、生物被膜活菌数以及清除已经成熟的生物被膜等。该文对这些有效的植物提取物及其活性成分进行了总结,并分析了其抗细菌生物被膜的作用机制。旨在为防治细菌生物被膜感染的植物类药物的开发提供参考。     

A review of the world's active seabird restoration projects

Within the past several decades, seabird populations have been actively restored in locales where they were reduced or extirpated. Chick translocation, acoustic vocalization playbacks, and decoys are now used widely to lure breeding seabirds to restoration sites. In this first worldwide review of seabird restoration projects we evaluate the factors affecting project success or failure and recommend future directions for management. We identified 128 active restoration projects that were implemented to protect 47 seabird species in 100 locales spanning 14 countries since active restoration methods were pioneered in 1973. Active seabird restoration can achieve conservation goals for threatened and endangered species, and for species affected by anthropogenic impacts (e.g., oil spills, invasive species, fisheries). It also can be used to relocate populations from undesired breeding locales to more favorable locations, and to establish multiple breeding locations to reduce risks posed by catastrophic events. Active restoration can help to restore ecological processes, as large seabird colonies function to cycle marine nutrients to terrestrial ecosystems and create habitats for commensal species. Active restoration is especially appropriate where the original causes of decline are no longer working to suppress colony establishment and growth. Successful restoration efforts require careful planning and long-term commitments. We introduce the different forms of active seabird restoration techniques, review their utility for different seabird species, and use case studies to suggest how to optimize this technique to restore seabird species globally. Wildlife managers can use this review to guide their seabird restoration projects in the planning, implementation, and monitoring stages; tailor their restoration to seabird-specific life histories; and identify areas for further research to improve restoration utility in the future. © 2011 The Wildlife Society.     

抗菌肽抗肿瘤作用的研究进展

抗菌肽是生物体抵御外界病原体侵袭时产生的一类保守的小分子多肽,是生物体内先天免疫防御机制的重要组分。抗菌肽可以选择性杀伤肿瘤细胞,而对正常细胞损害较小,已作为化、放疗药物潜在的替代品被广泛研究和开发。从抗菌肽对不同肿瘤细胞选择性作用机制、抗菌肽药物设计的发展及应用前景等方面进行综述。     

Killer toxins of clinically important yeasts

The review deals with some theoretical and applied aspects of the capacity of yeasts for synthesizing toxins. Similarly to antibiotic formation in micellar fungi and actinomycetes and the synthesis of bactericins in prokaryotes, yeast cells also have their mechanism of protection from other microorganisms. The substances, essentially of the same nature, synthesized by yeast are known for more than 30 years as mycocins or killer toxins. They are proteins or glycoproteins, active mainly against yeast microorganisms. Mycocins are not active against bacteria and protozoa exhibiting only fungicidal or fungistatic action. The formation of mycocins may be determined by nucleus or plasmid DNA. In this review information on killer toxins produced by clinically important yeasts of the genera Candida, Cryptococcus and Rhodotorula is systematized.     

Synthesis of pharmaceutically active compounds containing a disubstituted piperidine framework

The synthesis of pharmaceutically active compounds bearing a disubstituted piperidine framework is reviewed. Due to their frequent occurrence in pharmaceutical research, functionalized piperidines and the synthetic methodologies used for their preparation are of considerable topical interest. The present review focuses on the synthetic pathways used for the preparation of disubstituted piperidines and also briefly covers the activity and/or usage of the same.     

Chitosan-based polyelectrolyte complexes: a review

The review focuses on the formation of polyelectrolyte chitosan complexes with biologically active compounds and prospects of use thereof. The possibility of obtaining low-molecular-weight, water-soluble batches of chitosan, which differ in their degree of acetylation, is discussed, with emphasis on their use for binding nucleic acids into complexes.     

Membrane mechanisms of excretion of physiologically active substances by bacteria (review)

The review covers the evidence on the mechanisms of regulation of intracellular concentrations of low-molecular weight physiologically active substances, as well as of other intermediate or end metabolites by means of their excretion from bacterial cells. These processes can be considered as a particular level of metabolic regulation that can be called "membrane regulation".     

Study of cholinesterases of different origin by the method of inhibitor analysis (variation of structure of phosphoryl and leaving parts of dialkoxyphosphates)

Analytical review is performed of literature data on inhibitor analysis of structure of cholinesterases from different animals (vertebrates, insects, molluscs) by studying rate of their interaction with 190 dialkoxyphosphates of 54 homologous series with regularly changed structure of their phosphoryl group. The presented data are discussed from the point of view of comparative biochemistry and in the light of current concepts of structure of cholinesterase active center in animals at different levels of evolutionary development.     

Recent patents on the synthesis and application of silica nanoparticles for drug delivery

Drug delivery systems are designed to improve therapy efficacy as well as patient compliance. This could be accomplished by specifically targeting a medication intact to its active site, therefore reducing side-effects and enabling high local drug concentrations. Silica nanoparticles have gained ground in the biomedical field for their biocompatibility and biodegradability, being themselves inert and stable, thus enabling a variety of formulation designs for application in the pharmaceutical industry. This paper is a review of the recent patents on the applications of silica nanoparticles for drug delivery and their preparation. The review will focus on the different techniques available to obtain silica nanoparticles with variable morphology and their drug targeting applications, providing an overview of silica particles synthesis described in the literature.     

The Development of Pseudocapacitor Electrodes and Devices with High Active Mass Loading

Pseudocapacitive materials are used for supercapacitor applications due to their exceptionally high capacitance and low cost. Good capacitive performance of the pseudocapacitive materials at high active mass loadings is vital for the development of the next generation of supercapacitor devices. This review describes recent advances in materials and nanotechnologies, which allows the development of advanced pseudocapacitive devices with high active mass. An important breakthrough is the discovery of novel dispersing and capping agents for the colloidal processing of nanoparticles. Particularly important are novel co‐dispersants that exhibit enhanced adsorption on materials of different types, such as inorganic nanoparticles, carbon nanotubes, and graphene. Conceptually new strategies are designed to fabricate coated particles. Recent innovations pave the way for the development of multifunctional redox‐active dopants‐dispersants and dopants‐oxidants to manufacture conductive polymer composites. Among the most important advances in nanotechnology is the development of template methods and heterocoagulation techniques for composite manufacturing. The progress in the design of novel surface modification techniques and materials, discovery of advanced anchoring groups, and development of liquid–liquid extraction allows agglomerate‐free processing of nanomaterials and composites. This review describes fundamental aspects of novel technologies and their applications in the manufacturing of pseudocapacitive devices for energy storage.     

Application of reporter strains for screening of new antibiotics

Screening for new antibiotics remains an important area of biology and medicine. Elucidation of the antibiotic mechanism of action is an indispensable part for this type of research. Preferentially, it should be carried out quickly and cost-effectively, on the stage of primary screening. In this review we describe application of reporter strains for rapid classification of antibiotics by their mechanisms of action, without prior purification of active compounds and determination of their chemical structure.     

Investigation of cholinesterases of different origin by the method of inhibitor analysis (variation of structure of phosphoryl part of alkoxyalkylthiophosphonates)

Analytical review of literature data is carried out on inhibitor analysis of structure of cholinesterases in various animals (vertebrates, insects, and molluscs) by studying their interaction with 68 alkoxyalkylthiophosphonates of 10 homologous series with regularly changed structure of phosphoryl part. The presented data are discussed in the comparative-enzymological aspect of current concepts of structure of active center of cholinesterases.     

The longest micron; transporting poxviruses out of the cell

The large size of poxvirus virions (approximately 250-300 microm) makes them dependent on active transport for intracellular movement during infection. Several recent papers have reported the utilization of the microtubule network by poxviruses during viral egress and their use of conventional kinesin for intracellular transport. This review looks at recent reports of poxvirus intracellular transport for virion egress and their interaction with the microtubule network.