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Exopolymer
An exopolymer is a biopolymer that is secreted by an organism into the environment (i.e. external to the organism). These exopolymers include the biofilms produced by bacteria to anchor them and protect them from environmental conditions. One type of expolymer, Transparent Exopolymers (TEP), found in both marine and aquatic ecosystems, are planktonic acidic polysaccharides of a gel-like consistency, originally defined by their ability to be stained visible by acidic Alcian Blue. Their free-floating characteristic sets TEPs aside from other extracellular polymeric substance subgroups where exopolymers exists as cell coating, dissolved slime or as part of biofilm matrices. The formation of Transparent Exopolymer Particles(TEP) is mainly due to the abiotic coagulation of dissolved carbohydrates, which is secreted by the phytoplankton communities. Transparent Exopolymer Particles ((TEP) have the ability to form larger aggregates because of their strong surface active properties or “ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biofilm
A biofilm comprises any syntrophic consortium of microorganisms in which cells stick to each other and often also to a surface. These adherent cells become embedded within a slimy extracellular matrix that is composed of extracellular polymeric substances (EPSs). The cells within the biofilm produce the EPS components, which are typically a polymeric conglomeration of extracellular polysaccharides, proteins, lipids and DNA. Because they have three-dimensional structure and represent a community lifestyle for microorganisms, they have been metaphorically described as "cities for microbes". Biofilms may form on living or non-living surfaces and can be prevalent in natural, industrial, and hospital settings. They may constitute a microbiome or be a portion of it. The microbial cells growing in a biofilm are physiologically distinct from planktonic cells of the same organism, which, by contrast, are single cells that may float or swim in a liquid medium. Biofilms can form ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biopolymer
Biopolymers are natural polymers produced by the cells of living organisms. Like other polymers, biopolymers consist of monomeric units that are covalently bonded in chains to form larger molecules. There are three main classes of biopolymers, classified according to the monomers used and the structure of the biopolymer formed: polynucleotides, polypeptides, and polysaccharides. The Polynucleotides, RNA and DNA, are long polymers of nucleotides. Polypeptides include proteins and shorter polymers of amino acids; some major examples include collagen, actin, and fibrin. Polysaccharides are linear or branched chains of sugar carbohydrates; examples include starch, cellulose and alginate. Other examples of biopolymers include natural rubbers (polymers of isoprene), suberin and lignin (complex polyphenolic polymers), cutin and cutan (complex polymers of long-chain fatty acids) and melanin. In addition to their many essential roles in living organisms, biopolymers have applications in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polysaccharide
Polysaccharides (), or polycarbohydrates, are the most abundant carbohydrates found in food. They are long chain polymeric carbohydrates composed of monosaccharide units bound together by glycosidic linkages. This carbohydrate can react with water (hydrolysis) using amylase enzymes as catalyst, which produces constituent sugars (monosaccharides, or oligosaccharides). They range in structure from linear to highly branched. Examples include storage polysaccharides such as starch, glycogen and galactogen and structural polysaccharides such as cellulose and chitin. Polysaccharides are often quite heterogeneous, containing slight modifications of the repeating unit. Depending on the structure, these macromolecules can have distinct properties from their monosaccharide building blocks. They may be amorphous or even insoluble in water. When all the monosaccharides in a polysaccharide are the same type, the polysaccharide is called a homopolysaccharide or homoglycan, but when more t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alcian Blue Stain
Alcian blue () is any member of a family of polyvalent basic dyes, of which the Alcian blue 8G (also called Ingrain blue 1, and C.I. 74240, formerly called Alcian blue 8GX from the name of a batch of an Imperial Chemical Industries, ICI product) has been historically the most common and the most reliable member. It is used staining, to stain acidic polysaccharides such as glycosaminoglycans in cartilages and other body structures, some types of mucopolysaccharides, sialylated glycocalyx of cells etc. For many of these targets it is one of the most widely used cationic dyes for both Optical microscope, light and Electron microscope, electron microscopy. Use of alcian blue has historically been a popular staining method in histology especially for light microscopy in paraffin embedded sections and in semithin resin sections. The tissue parts that specifically stain by this dye become blue to bluish-green after staining and are called "Alcianophilic" (comparable to "eosinophilic" or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extracellular Polymeric Substance
Extracellular polymeric substances (EPSs) are natural polymers of high molecular weight secreted by microorganisms into their environment. EPSs establish the functional and structural integrity of biofilms, and are considered the fundamental component that determines the physicochemical properties of a biofilm. EPS in the matrix of biofilms provides compositional support and protection of microbial communities from the harsh environments. Components of EPS can be of different classes of polysaccharides, lipids, nucleic acids, proteins, Lipopolysaccharides, and minerals. Components EPSs are mostly composed of polysaccharides (exopolysaccharides) and proteins, but include other macromolecules such as DNA, lipids and humic substances. EPSs are the construction material of bacterial settlements and either remain attached to the cell's outer surface, or are secreted into its growth medium. These compounds are important in biofilm formation and cells' attachment to surfaces. EPSs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon Cycle
The carbon cycle is the biogeochemical cycle by which carbon is exchanged among the biosphere, pedosphere, geosphere, hydrosphere, and Earth's atmosphere, atmosphere of the Earth. Carbon is the main component of biological compounds as well as a major component of many minerals such as limestone. Along with the nitrogen cycle and the water cycle, the carbon cycle comprises a sequence of events that are key to make Earth capable of sustaining life. It describes the movement of carbon as it is recycled and reused throughout the biosphere, as well as long-term processes of carbon sequestration to and release from carbon sinks. Carbon sinks in the land and the ocean each currently take up about one-quarter of anthropogenic carbon emissions each year. Humans have disturbed the biological carbon cycle for many centuries by modifying land use, and moreover with the recent industrial-scale mining of fossil carbon (coal, petroleum and natural gas, gas extraction, and cement manufacture) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biomolecules
A biomolecule or biological molecule is a loosely used term for molecules present in organisms that are essential to one or more typically biological processes, such as cell division, morphogenesis, or development. Biomolecules include large macromolecules (or polyelectrolytes) such as proteins, carbohydrates, lipids, and nucleic acids, as well as small molecules such as primary metabolites, secondary metabolites and natural products. A more general name for this class of material is biological materials. Biomolecules are an important element of living organisms, those biomolecules are often endogenous, produced within the organism but organisms usually need exogenous biomolecules, for example certain nutrients, to survive. Biology and its subfields of biochemistry and molecular biology study biomolecules and their reactions. Most biomolecules are organic compounds, and just four elements—oxygen, carbon, hydrogen, and nitrogen—make up 96% of the human body's mass. But ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
