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MHETase
The Enzyme MHETase is a hydrolase, which was discovered in 2016. It cleaves Mono-(2-hydroxyethyl)terephthalic acid, the PET degradation product by PETase, to ethylene glycol and terephthalic acid. This pair of enzymes, PETase and MHETase, enable the bacterium ''Ideonella sakaiensis'' to live on the plastic PET as sole carbon source. Chemical reaction The first enzyme of the PET degradation pathway, PETase, cleaves this plastic into the intermediates MHET ( Mono-(2-hydroxyethyl)terephthalic acid) and minor amounts BHET ( Bis-(2-hydroxyethyl)terephthalic acid). MHETase hydrolyses the ester bond of MHET forming terephthalic acid and ethylene glycol. Besides its natural substrate MHET the chromogenic substrate MpNPT, Mono-p-nitrophenyl-terephthalate, is also hydrolyzed well. This can be used to measure the enzymatic activity and determine the kinetic parameters. Ferulate and gallate esters, substrates of the closest relatives in the tannase family, are not converted. p-Nitropheny ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ideonella Sakaiensis
''Ideonella sakaiensis'' is a bacterium from the genus'' Ideonella'' and family Comamonadaceae capable of breaking down and consuming the plastic polyethylene terephthalate (PET) using it as both a carbon and energy source. The bacterium was originally isolated from a sediment sample taken outside of a plastic bottle recycling facility in Sakai City, Japan. * Discovery ''Ideonella sakaiensis'' was first identified in 2016 by a team of researchers led by Kohei Oda of Kyoto Institute of Technology and Kenji Miyamoto of Keio University after collecting a sample of PET-contaminated sediment at a plastic bottle recycling facility in Sakai, Japan. The bacteria was first isolated from a consortium of microorganisms in the sediment sample, which included protozoa and yeast-like cells. The entire microbial community was shown to mineralize 75% of the degraded PET into carbon dioxide once it had been initially degraded and assimilated by ''Ideonella sakaiensis''. Characterization Phys ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PETase
PETases are an esterase class of enzymes that catalyze the hydrolysis of polyethylene terephthalate (PET) plastic to monomeric mono-2-hydroxyethyl terephthalate (MHET). The idealized chemical reaction is (where n is the number of monomers in the polymer chain): :(ethylene terephthalate)n + H2O → (ethylene terephthalate)n-1 + MHET Trace amount of the PET breaks down to bis(2-hydroxyethyl) terephthalate (BHET). PETases can also break down PEF-plastic ( polyethylene-2,5-furandicarboxylate), which is a bioderived PET replacement, into the analogous . PETases can't catalyze the hydrolysis of aliphatic polyesters like polybutylene succinate or polylactic acid. Non-enzymatic natural degradation of PET will take hundreds of years, but PETases can degrade PET in matter of days. History The first PETase was discovered in 2016 from ''Ideonella sakaiensis'' strain 201-F6 bacteria found from sludge samples collected close to a Japanese PET bottle recycling site. Other types of PET degradi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terephthalic Acid
Terephthalic acid is an organic compound with formula C6H4(CO2H)2. This white solid is a commodity chemical, used principally as a precursor to the polyester PET, used to make clothing and plastic bottles. Several million tonnes are produced annually. The common name is derived from the turpentine-producing tree ''Pistacia terebinthus'' and phthalic acid. History Terephthalic acid was first isolated (from turpentine) by the French chemist Amédée Cailliot (1805–1884) in 1846. Terephthalic acid became industrially important after World War II. Terephthalic acid was produced by oxidation of ''p''-xylene with dilute nitric acid. Air oxidation of ''p''-xylene gives ''p''-toluic acid, which resists further air-oxidation. Conversion of ''p''-toluic acid to methyl p-toluate (CH3C6H4CO2CH3) opens the way for further oxidation to monomethyl terephthalate, which is further esterified to dimethyl terephthalate. In 1955, Mid-Century Corporation and ICI announced the bromide-promoted oxida ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. Almost all metabolic processes in the cell need enzyme catalysis in order to occur at rates fast enough to sustain life. Metabolic pathways depend upon enzymes to catalyze individual steps. The study of enzymes is called ''enzymology'' and the field of pseudoenzyme analysis recognizes that during evolution, some enzymes have lost the ability to carry out biological catalysis, which is often reflected in their amino acid sequences and unusual 'pseudocatalytic' properties. Enzymes are known to catalyze more than 5,000 biochemical reaction types. Other biocatalysts are catalytic RNA molecules, called ribozymes. Enzymes' specificity comes from their unique three-dimensional structures. Like all catalysts, enzymes increase the reaction ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrolase
Hydrolase is a class of enzyme that commonly perform as biochemical catalysts that use water to break a chemical bond, which typically results in dividing a larger molecule into smaller molecules. Some common examples of hydrolase enzymes are esterases including lipases, phosphatases, glycosidases, peptidases, and nucleosidases. Esterases cleave ester bonds in lipids and phosphatases cleave phosphate groups off molecules. An example of crucial esterase is acetylcholine esterase, which assists in transforming the neuron impulse into the acetate group after the hydrolase breaks the acetylcholine into choline and acetic acid. Acetic acid is an important metabolite in the body and a critical intermediate for other reactions such as glycolysis. Lipases hydrolyze glycerides. Glycosidases cleave sugar molecules off carbohydrates and peptidases hydrolyze peptide bonds. Nucleosidases hydrolyze the bonds of nucleotides. Hydrolase enzymes are important for the body because they have degra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2-Hydroxyethyl Terephthalic Acid
2-Hydroxyethyl terephthalic acid is an organic compound with the formula HOC2H4O2CC6H4CO2H. It is the monoester of terephthalic acid and ethylene glycol. The compound is a precursor to poly(ethylene terephthalate) (PET), a polymer that is produced on a large scale industrially. 2-Hydroxyethyl terephthalic acid is a colorless solid that is soluble in water and polar organic solvents. Near neutral pH, 2-hydroxyethyl terephthalic acid converts to 2-hydroxyethyl terephthalate, HOC2H4O2CC6H4CO2−. Occurrence and reactions 2-Hydroxyethyl terephthalic acid is an intermediate in both the formation and hydrolysis of PET. It is produced on a massive scale as the first intermediate in certain routes to PET. Specifically, it is produced in the course of the thermal condensation of terephthalic acid and ethylene glycol: :HOC2H4OH + HO2CC6H4CO2H → HOC2H4O2CC6H4CO2H + H2O Further dehydration of 2-hydroxyethyl terephthalic acid gives PET. It is also produced by the partial hydrolys ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethylene Glycol
Ethylene glycol (IUPAC name: ethane-1,2-diol) is an organic compound (a vicinal diol) with the formula . It is mainly used for two purposes, as a raw material in the manufacture of polyester fibers and for antifreeze formulations. It is an odorless, colorless, flammable, viscous liquid. Ethylene glycol has a sweet taste, but it is toxic in high concentrations. Production Industrial routes Ethylene glycol is produced from ethylene (ethene), via the intermediate ethylene oxide. Ethylene oxide reacts with water to produce ethylene glycol according to the chemical equation: This reaction can be catalyzed by either acids or bases, or can occur at neutral pH under elevated temperatures. The highest yields of ethylene glycol occur at acidic or neutral pH with a large excess of water. Under these conditions, ethylene glycol yields of 90% can be achieved. The major byproducts are the oligomers diethylene glycol, triethylene glycol, and tetraethylene glycol. The separation of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mono(2-hydroxyethyl)-isophthalate
Mono may refer to: Common meanings * Infectious mononucleosis, "the kissing disease" * Monaural, monophonic sound reproduction, often shortened to mono * Mono-, a numerical prefix representing anything single Music Performers * Mono (Japanese band), an instrumental band * Mono (UK band), an electronic band * Miky Mono, former member of Mono Inc., a German gothic rock band * Richard Targett and the Monos, a side-project to The Trudy Albums * ''Mono'' (Alpha Wolf album) or the title song, 2017 * ''Mono'' (Fury in the Slaughterhouse album), 1993 * ''Mono'' (The Icarus Line album), 2001 * ''Mono'' (Lena Katina album) or the title song, 2019 * ''Mono'' (The Mavericks album), 2015 * ''Mono'' (mixtape), by RM, 2018 * ''Mono'', by Paul Westerberg, packaged with ''Stereo'', 2002 Songs * "Mono" (song), by Courtney Love, 2004 * "Mono", by Fightstar from ''They Liked You Better When You Were Dead'', 2005 * "Mono", by Monrose from ''Ladylike'', 2010 * "Mono", by Whitechapel from ''O ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mono(2-hydroxyethyl)-furanoate
Mono may refer to: Common meanings * Infectious mononucleosis, "the kissing disease" * Monaural, monophonic sound reproduction, often shortened to mono * Mono-, a numerical prefix representing anything single Music Performers * Mono (Japanese band), an instrumental band * Mono (UK band), an electronic band * Miky Mono, former member of Mono Inc., a German gothic rock band * Richard Targett and the Monos, a side-project to The Trudy Albums * ''Mono'' (Alpha Wolf album) or the title song, 2017 * ''Mono'' (Fury in the Slaughterhouse album), 1993 * ''Mono'' (The Icarus Line album), 2001 * ''Mono'' (Lena Katina album) or the title song, 2019 * ''Mono'' (The Mavericks album), 2015 * ''Mono'' (mixtape), by RM, 2018 * ''Mono'', by Paul Westerberg, packaged with ''Stereo'', 2002 Songs * "Mono" (song), by Courtney Love, 2004 * "Mono", by Fightstar from ''They Liked You Better When You Were Dead'', 2005 * "Mono", by Monrose from ''Ladylike'', 2010 * "Mono", by Whitechapel from ''O ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein Engineering
Protein engineering is the process of developing useful or valuable proteins. It is a young discipline, with much research taking place into the understanding of protein folding and recognition for protein design principles. It has been used to improve the function of many enzymes for industrial catalysis. It is also a product and services market, with an estimated value of $168 billion by 2017. There are two general strategies for protein engineering: rational protein design and directed evolution. These methods are not mutually exclusive; researchers will often apply both. In the future, more detailed knowledge of protein structure and function, and advances in high-throughput screening, may greatly expand the abilities of protein engineering. Eventually, even unnatural amino acids may be included, via newer methods, such as expanded genetic code, that allow encoding novel amino acids in genetic code. Approaches Rational design In rational protein design, a scientist uses ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
