|
Microcompartment
Bacterial microcompartments (BMCs) are organelle-like structures found in bacteria. They consist of a protein shell that encloses enzymes and other proteins. BMCs are typically about 40–200 nanometers in diameter and are made entirely of proteins. The shell functions like a membrane, as it is selectively permeable. Other protein-based compartments found in bacteria and archaea include encapsulin nanocompartments and gas vesicles. Discovery The first BMCs were observed in the 1950s in electron micrographs of cyanobacteria, and were later named carboxysomes after their role in carbon fixation was established. Until the 1990s, carboxysomes were thought to be an oddity confined to certain autotrophic bacteria. But then genes coding for proteins homologous to those of the carboxysome shell were identified in the ''pdu'' (propanediol utilization) and ''eut'' (ethanolamine utilization) operons. Subsequently, transmission electron micrographs of ''Salmonella'' cells grown on propanedi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carboxysome And Bacterial Microcompartments
Carboxysomes are bacterial microcompartments (BMCs) consisting of polyhedral protein shells filled with the enzymes ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO)—the predominant enzyme in carbon fixation and the Rate-determining step, rate limiting enzyme in the Calvin cycle—and carbonic anhydrase. Carboxysomes are thought to have evolved as a consequence of the increase in oxygen concentration in the ancient atmosphere; this is because oxygen is a competing substrate to carbon dioxide in the RuBisCO reaction. To overcome the inefficiency of RuBisCO, carboxysomes concentrate carbon dioxide inside the shell by means of co-localized carbonic anhydrase activity, which produces carbon dioxide from the bicarbonate that diffuses into the carboxysome. The resulting concentration of carbon dioxide near RuBisCO decreases the proportion of ribulose-1,5-bisphosphate oxygenation and thereby avoids costly Photorespiration, photorespiratory reactions. The surrounding she ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carboxysomes EM
Carboxysomes are bacterial microcompartments (BMCs) consisting of polyhedral protein shells filled with the enzymes ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO)—the predominant enzyme in carbon fixation and the rate limiting enzyme in the Calvin cycle—and carbonic anhydrase. Carboxysomes are thought to have evolved as a consequence of the increase in oxygen concentration in the ancient atmosphere; this is because oxygen is a competing substrate to carbon dioxide in the RuBisCO reaction. To overcome the inefficiency of RuBisCO, carboxysomes concentrate carbon dioxide inside the shell by means of co-localized carbonic anhydrase activity, which produces carbon dioxide from the bicarbonate that diffuses into the carboxysome. The resulting concentration of carbon dioxide near RuBisCO decreases the proportion of ribulose-1,5-bisphosphate oxygenation and thereby avoids costly photorespiratory reactions. The surrounding shell provides a barrier to carbon dioxid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organelle
In cell biology, an organelle is a specialized subunit, usually within a cell, that has a specific function. The name ''organelle'' comes from the idea that these structures are parts of cells, as organs are to the body, hence ''organelle,'' the suffix ''-elle'' being a diminutive. Organelles are either separately enclosed within their own lipid bilayers (also called membrane-bound organelles) or are spatially distinct functional units without a surrounding lipid bilayer (non-membrane bound organelles). Although most organelles are functional units within cells, some function units that extend outside of cells are often termed organelles, such as cilia, the flagellum and archaellum, and the trichocyst. Organelles are identified by microscopy, and can also be purified by cell fractionation. There are many types of organelles, particularly in eukaryotic cells. They include structures that make up the endomembrane system (such as the nuclear envelope, endoplasmic reticulum, and G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyanobacteria
Cyanobacteria (), also known as Cyanophyta, are a phylum of gram-negative bacteria that obtain energy via photosynthesis. The name ''cyanobacteria'' refers to their color (), which similarly forms the basis of cyanobacteria's common name, blue-green algae, although they are not usually scientifically classified as algae. They appear to have originated in a freshwater or terrestrial environment. Sericytochromatia, the proposed name of the paraphyletic and most basal group, is the ancestor of both the non-photosynthetic group Melainabacteria and the photosynthetic cyanobacteria, also called Oxyphotobacteria. Cyanobacteria use photosynthetic pigments, such as carotenoids, phycobilins, and various forms of chlorophyll, which absorb energy from light. Unlike heterotrophic prokaryotes, cyanobacteria have internal membranes. These are flattened sacs called thylakoids where photosynthesis is performed. Phototrophic eukaryotes such as green plants perform photosynthesis in plast ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacteria
Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of 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 soil, water, acidic hot springs, radioactive waste, and the deep biosphere of Earth's crust. Bacteria are vital in many stages of the nutrient cycle by recycling nutrients such as the fixation of nitrogen from the atmosphere. The nutrient cycle includes the decomposition of 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, such as hydrogen sulphide and methane, to energy. Bacteria also live in symbiotic and parasitic relationsh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Applied And Environmental Microbiology
''Applied and Environmental Microbiology'' is a biweekly peer-reviewed scientific journal published by the American Society for Microbiology. It was established in 1953 as ''Applied Microbiology'' and obtained its current name in 1975. Articles older than six months are available free of cost from the website, however, the newly published articles within six months are available to subscribers only. According to the ''Journal Citation Reports'', the journal has a 2021 impact factor of 5.005. The journal has been ranked as one of the top 100 journals over the past 100 years in the fields of biology and medicine.Special Libraries Association100 Journals in last 100 years/ref> The editor-in-chief is Gemma Reguera (Michigan State University Michigan State University (Michigan State, MSU) is a public university, public Land-grant university, land-grant research university in East Lansing, Michigan. It was founded in 1855 as the Agricultural College of the State of Michigan, the fi . ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of Experimental Botany
The ''Journal of Experimental Botany'' (''JXB'') is a peer-reviewed scientific journal published by Oxford University Press on behalf of the Society for Experimental Biology. It covers research on plant biology, focusing on molecular physiology, molecular genetics, and environmental physiology. Some of its content is available under an open access licence. The editor-in-chief is John Lunn (Max Planck Institute of Molecular Plant Physiology). Research is published in five key areas: growth and development, cell biology, metabolism, plant-environment interactions, and crop molecular genetics. References External links * Submission websiteSociety for Experimental Biology websiteJournal of Experimental Botanyat SCImago Journal Rank Journal of Experimental Botanyat HathiTrust HathiTrust Digital Library is a large-scale collaborative repository of digital content from research libraries including content digitized via Google Books and the Internet Archive digitization initiative ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Murray R
Murray may refer to: Businesses * Murray (bicycle company), an American manufacturer of low-cost bicycles * Murrays, an Australian bus company * Murray International Trust, a Scottish investment trust * D. & W. Murray Limited, an Australian wholesale drapery business * John Murray (publishing house), a British publishing house Fictional characters *Murray Monster, a muppet in ''Sesame Street'' *Little Murray Sparkles, a List of Sesame Street Muppets , cat in ''Sesame Street'' *Murray (Monkey Island), Murray (''Monkey Island''), a character in the video game series *Murray (Sly Cooper), Murray (''Sly Cooper''), a character in the video game series *Murray Slaughter, a regular character in ''The Mary Tyler Moore Show'' *Murray, the mascot of the band Dio_(band)#Murray, Dio *Murray, in the 2015 Netflix series ''Richie Rich (2015 TV series), Richie Rich'' *Murray, a List_of_Hotel_Transylvania_characters#Murray, ''Hotel Transylvania'' character *Murray the Cop, in ''Fat Pizza'' *Murray ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of Bacteriology
The ''Journal of Bacteriology'' is a biweekly peer-reviewed scientific journal established in 1916. It is published by the American Society for Microbiology and the editor in chief is George A. O'Toole (Dartmouth College). The journal is delayed open access: content is available for free at the journal's website and at PubMed Central after a six-month embargo. The journal is also hybrid open access allowing authors to pay an article processing fee for their articles to be available for free immediately. Abstracting and indexing The journal is abstracted and indexed in: According to the ''Journal Citation Reports'', the journal has a 2020 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a scientometric index calculated by Clarivate that reflects the yearly mean number of citations of articles published in the last two years in a given journal, as i ... of 3.490. References External links *{{Official website, http://jb.asm.org/ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pentameric Protein
A pentameric protein is a quaternary protein structure that consists of five protein subunits. Examples Ligand-gated ion channels Five sub-units come together to form a channel. Each channel consist of two alpha chain, one beta, one gamma and one delta chain. These five chains assemble together (along with certain receptors like protons or acetylcholine) forming the structure of the channel. A ligand-gated ion channel on the post-synaptic junction of the muscle-end plate is an example of such a channel. They are acetylcholine-operated ion channels, which means that acetylcholine brings about a conformational change. The channel allows the free movement of the cations like Na and K when acetylcholine binds to its receptors. Viral capsids Many viral capsids are formed by hexameric and pentameric proteins. Such capsids are assigned a triangulation number (T-number) which describe relation between the number of pentagons and hexagons. Carboxysomes Protein enclosing bacterial organe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Substrate Channeling
Substrate channeling is the passing of the intermediary metabolic product of one enzyme directly to another enzyme or active site without its release into solution. When several consecutive enzymes of a metabolic pathway channel substrates between themselves, this is called a metabolon. Channeling can make a metabolic pathway more rapid and efficient than it would be if the enzymes were randomly distributed in the cytosol, or prevent the release of unstable intermediates. It can also protect an intermediate from being consumed by competing reactions catalyzed by other enzymes. Channeling can occur in several ways. One possibility, which occurs in the pyruvate dehydrogenase complex, is by a substrate being attached to a flexible arm that moves between several active sites (not very likely). Another possibility is by two active sites being connected by a tunnel through the protein and the substrate moving through the tunnel; this is seen in tryptophan synthase. A third possibility is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metabolic Pathway
In biochemistry, a metabolic pathway is a linked series of chemical reactions occurring within a cell. The reactants, products, and intermediates of an enzymatic reaction are known as metabolites, which are modified by a sequence of chemical reactions catalyzed by enzymes. In most cases of a metabolic pathway, the product of one enzyme acts as the substrate for the next. However, side products are considered waste and removed from the cell. These enzymes often require dietary minerals, vitamins, and other cofactors to function. Different metabolic pathways function based on the position within a eukaryotic cell and the significance of the pathway in the given compartment of the cell. For instance, the, electron transport chain, and oxidative phosphorylation all take place in the mitochondrial membrane. In contrast, glycolysis, pentose phosphate pathway, and fatty acid biosynthesis all occur in the cytosol of a cell. There are two types of metabolic pathways that are character ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
