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Bioplastics can be made from proteins from different sources. For example, wheat gluten and casein show promising properties as a raw material for different biodegradable polymers. [41] Additionally, soy protein is being considered as another source of bioplastic. Soy proteins have been used in plastic production for over one hundred years.
Other applications, including polycarbonate sheets, may have the anti-UV layer added as a special coating or a coextrusion for enhanced weathering resistance. Polycarbonate is also used as a printing substrate for nameplate and other forms of industrial grade under printed products. The polycarbonate provides a barrier to wear, the elements ...
Protein precursors are often used by an organism when the subsequent protein is potentially harmful, but needs to be available on short notice and/or in large quantities. Enzyme precursors are called zymogens or proenzymes. Examples are enzymes of the digestive tract in humans. Some protein precursors are secreted from the cell.
A polycarbonate is an oxocarbon dianion consisting of a chain of carbonate units, where successive carbonyl groups are directly linked to each other by shared additional oxygen atoms. That is, they are the conjugate bases of polycarbonic acids , the conceptual anhydrides of carbonic acid , or polymers of carbon dioxide .
An example is the reaction of phosgene with bisphenol A to form polycarbonates. [9] Phosgenation of diamines gives di-isocyanates, like toluene diisocyanate (TDI), methylene diphenyl diisocyanate (MDI), hexamethylene diisocyanate (HDI), and isophorone diisocyanate (IPDI). In these conversions, phosgene is used in excess to increase yield and ...
In chemistry, a precursor is a compound that participates in a chemical reaction that produces another compound. In biochemistry , the term "precursor" often refers more specifically to a chemical compound preceding another in a metabolic pathway , such as a protein precursor .
Proteins are often synthesized in an inactive precursor form; typically, an N-terminal or C-terminal segment blocks the active site of the protein, inhibiting its function. The protein is activated by cleaving off the inhibitory peptide. Some proteins even have the power to cleave themselves.
The cyclotide precursor is comprised a hydrophobic Signal peptide that targets the precursor to the Endoplasmic Reticulum (ER), an N-terminal propeptide that then targets it to the vacuole, a cyclotide domain and a final C-terminal propeptide necessary for cyclisation.The cyclotide domain folds in the ER, after which it is trafficked to the ...