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Lactacystin
Lactacystin is an organic compound naturally synthesized by bacteria of the genus ''Streptomyces'' first identified as an inducer of neuritogenesis in neuroblastoma cells in 1991.Omura S, Fujimoto T, Otoguro K, Matsuzaki K, Moriguchi R, Tanaka H, Sasaki Y. (1991). Lactacystin, a novel microbial metabolite, induces neuritogenesis of neuroblastoma cells: S. Omura, et al. ''J. Antibiot.'' 44(1):113-6. The target of lactacystin was subsequently found to be the proteasome on the basis of its affinity for certain catalytic subunits of the proteasome by Fenteany and co-workers in 1995. The proteasome is a protein complex responsible for the bulk of proteolysis in the cell, as well as proteolytic activation of certain protein substrates. Lactacystin was the first non-peptidic proteasome inhibitor discovered and is widely used as a research tool in biochemistry and cell biology. The transformation product of lactacystin clasto-lactacystin β-lactone (also known as omuralide) covalently modi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proteasome
Proteasomes are essential protein complexes responsible for the degradation of proteins by proteolysis, a chemical reaction that breaks peptide bonds. Enzymes that help such reactions are called proteases. Proteasomes are found inside all eukaryotes and archaea, and in some bacteria. In eukaryotes, proteasomes are located both in the nucleus and in the cytoplasm. The proteasomal degradation pathway is essential for many cellular processes, including the cell cycle, the regulation of gene expression, and responses to oxidative stress. The importance of proteolytic degradation inside cells and the role of ubiquitin in proteolytic pathways was acknowledged in the award of the 2004 Nobel Prize in Chemistry to Aaron Ciechanover, Avram Hershko and Irwin Rose. The core 20S proteasome (blue in the adjacent figure) is a cylindrical, compartmental protein complex of four stacked rings forming a central pore. Each ring is composed of seven individual proteins. The inner two rings a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Satoshi Ōmura
is a Japanese biochemist. He is known for the discovery and development of hundreds of pharmaceuticals originally occurring in microorganisms. In 2015, he was awarded the Nobel Prize in Physiology or Medicine jointly with William C. Campbell for their role in the discovery of avermectins and ivermectin, the world's first endectocide and a safe and highly effective microfilaricide. It is believed that the large molecular size of ivermectin prevents it from crossing the blood/aqueous humour barrier, and renders the drug an important treatment of helminthically-derived blindness. Early life and education Satoshi Ōmura was born in Nirasaki, Yamanashi Japan in 1935, the second son of Ōmura family. After graduating from the University of Yamanashi in 1958, he was appointed to science teacher at Tokyo Metropolitan Sumida Tech High School. In 1960, he became an auditor of Koji Nakanishi’s course at Tokyo University of Education, one year later, he enrolled in the Tokyo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Compound
Some chemical authorities define an organic compound as a chemical compound that contains a carbon–hydrogen or carbon–carbon bond; others consider an organic compound to be any chemical compound that contains carbon. For example, carbon-containing compounds such as alkanes (e.g. methane ) and its derivatives are universally considered organic, but many others are sometimes considered inorganic, such as certain compounds of carbon with nitrogen and oxygen (e.g. cyanide ion , hydrogen cyanide , chloroformic acid , carbon dioxide , and carbonate ion ). Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. The study of the properties, reactions, and syntheses of organic compounds comprise the discipline known as organic chemistry. For historical reasons, a few classes of carbon-containing compounds (e.g., carbonate salts and cyanide salts), along with a few other exceptions (e.g., carbon dioxide, and even ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Synthesis
Organic synthesis is a branch of chemical synthesis concerned with the construction of organic compounds. Organic compounds are molecules consisting of combinations of covalently-linked hydrogen, carbon, oxygen, and nitrogen atoms. Within the general subject of organic synthesis, there are many different types of synthetic routes that can be completed including total synthesis, Enantioselective synthesis, stereoselective synthesis, automated synthesis, and many more. Additionally, in understanding organic synthesis it is necessary to be familiar with the methodology, techniques, and applications of the subject. Total synthesis A total synthesis refers to the complete chemical synthesis of molecules from simple, Precursor (chemistry), natural precursors. Total synthesis is accomplished either via a linear or convergent approach. In a Linear synthesis, ''linear'' synthesis—often adequate for simple structures—several steps are performed sequentially until the molecule is com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacteria
Bacteria (; : bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of Prokaryote, prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit the air, soil, water, Hot spring, acidic hot springs, radioactive waste, and the deep biosphere of Earth's crust. Bacteria play a vital role in many stages of the nutrient cycle by recycling nutrients and the nitrogen fixation, fixation of nitrogen from the Earth's atmosphere, atmosphere. The nutrient cycle includes the decomposition of cadaver, dead bodies; bacteria are responsible for the putrefaction stage in this process. In the biological communities surrounding hydrothermal vents and cold seeps, extremophile bacteria provide the nutrients needed to sustain life by converting dissolved compounds, suc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genus
Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In binomial nomenclature, the genus name forms the first part of the binomial species name for each species within the genus. :E.g. ''Panthera leo'' (lion) and ''Panthera onca'' (jaguar) are two species within the genus ''Panthera''. ''Panthera'' is a genus within the family Felidae. The composition of a genus is determined by taxonomy (biology), taxonomists. The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful: # monophyly – all descendants of an ancestral taxon are grouped together (i.e. Phylogeneti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Streptomyces
''Streptomyces'', from στρεπτός (''streptós''), meaning "twisted", and μύκης (''múkés''), meaning "fungus", is the largest genus of Actinomycetota, and the type genus of the family Streptomycetaceae. Over 700 species of ''Streptomyces'' bacteria have been described. As with the other Actinomycetota, streptomycetes are gram-positive, and have very large genomes with high GC content. Found predominantly in soil and decaying vegetation, most streptomycetes produce spores, and are noted for their distinct "earthy" odor that results from production of a volatile metabolite, geosmin. Different strains of the same species may colonize very diverse environments. Streptomycetes are characterised by a complex secondary metabolism. Between 5-23% (average: 12%) of the protein-coding genes of each ''Streptomyces'' species are implicated in secondary metabolism. Streptomycetes produce over two-thirds of the clinically useful antibiotics of natural origin (e.g., neomy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Threonine Protease
Threonine proteases are a family of proteolytic enzymes harbouring a threonine (Thr) residue within the active site. The prototype members of this class of enzymes are the catalytic subunits of the proteasome, however, the acyltransferases convergently evolved the same active site geometry and mechanism. Mechanism Threonine proteases use the secondary alcohol of their N-terminal threonine as a nucleophile to perform catalysis. The threonine must be N-terminal since the terminal amine of the same residue acts as a general base by polarising an ordered water which deprotonates the alcohol to increase its reactivity as a nucleophile. Catalysis takes place in two steps: * Firstly the nucleophile attacks the substrate to form a covalent acyl-enzyme intermediate, releasing the first product. * Secondly the intermediate is hydrolysed by water to regenerate the free enzyme and release the second product. ** In ornithine acyltransferase, instead of water, the substrate ornithine ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biochemistry
Biochemistry, or biological chemistry, is the study of chemical processes within and relating to living organisms. A sub-discipline of both chemistry and biology, biochemistry may be divided into three fields: structural biology, enzymology, and metabolism. Over the last decades of the 20th century, biochemistry has become successful at explaining living processes through these three disciplines. Almost all List of life sciences, areas of the life sciences are being uncovered and developed through biochemical methodology and research.#Voet, Voet (2005), p. 3. Biochemistry focuses on understanding the chemical basis that allows biomolecule, biological molecules to give rise to the processes that occur within living Cell (biology), cells and between cells,#Karp, Karp (2009), p. 2. in turn relating greatly to the understanding of tissue (biology), tissues and organ (anatomy), organs as well as organism structure and function.#Miller, Miller (2012). p. 62. Biochemistry is closely ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Biology
Cell biology (also cellular biology or cytology) is a branch of biology that studies the structure, function, and behavior of cells. All living organisms are made of cells. A cell is the basic unit of life that is responsible for the living and functioning of organisms. Cell biology is the study of the structural and functional units of cells. Cell biology encompasses both prokaryotic and eukaryotic cells and has many subtopics which may include the study of cell metabolism, cell communication, cell cycle, biochemistry, and cell composition. The study of cells is performed using several microscopy techniques, cell culture, and cell fractionation. These have allowed for and are currently being used for discoveries and research pertaining to how cells function, ultimately giving insight into understanding larger organisms. Knowing the components of cells and how cells work is fundamental to all biological sciences while also being essential for research in biomedical fiel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Total Synthesis
Total synthesis, a specialized area within organic chemistry, focuses on constructing complex organic compounds, especially those found in nature, using laboratory methods. It often involves synthesizing natural products from basic, commercially available starting materials. Total synthesis targets can also be organometallic or inorganic. While total synthesis aims for complete construction from simple starting materials, modifying or partially synthesizing these compounds is known as semisynthesis. Natural product synthesis serves as a critical tool across various scientific fields. In organic chemistry, it tests new synthetic methods, validating and advancing innovative approaches. In medicinal chemistry, natural product synthesis is essential for creating bioactive compounds, driving progress in drug discovery and therapeutic development. Similarly, in chemical biology, it provides research tools for studying biological systems and processes. Additionally, synthesis aids natur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PubMed
PubMed is an openly accessible, free database which includes primarily the MEDLINE database of references and abstracts on life sciences and biomedical topics. The United States National Library of Medicine (NLM) at the National Institutes of Health maintains the database as part of the Entrez system of information retrieval. From 1971 to 1997, online access to the MEDLINE database was provided via computer and phone lines primarily through institutional facilities, such as university libraries. PubMed, first released in January 1996, ushered in the era of private, free, home- and office-based MEDLINE searching. The PubMed system was offered free to the public starting in June 1997. Content In addition to MEDLINE, PubMed provides access to: * older references from the print version of '' Index Medicus'', back to 1951 and earlier * references to some journals before they were indexed in Index Medicus and MEDLINE, for instance ''Science'', '' BMJ'', and ''Annals of Surg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
