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Recent studies [citation needed] have shown that the manipulation of pectinesterase expression can influence numerous physiological processes. In plants, pectinesterase plays a role in the modulation of cell wall mechanical stability during fruit ripening, cell wall extension during pollen germination and pollen tube growth, abscission, stem elongation, tuber yield and root development.
Pectin is composed of complex polysaccharides that are present in the primary cell walls of a plant, and are abundant in the green parts of terrestrial plants. [5] Pectin is the principal component of the middle lamella, where it binds cells. Pectin is deposited by exocytosis into the cell wall via vesicles produced in the Golgi apparatus. [6]
It is useful because pectin is the jelly-like matrix which helps cement plant cells together and in which other cell wall components, such as cellulose fibrils, are embedded. Therefore, pectinase enzymes are commonly used in processes involving the degradation of plant materials, such as speeding up the extraction of fruit juice from fruit ...
The mechanism is affected by the stability of the resulting cationic species. For example, if the atom bearing the positive charge is stabilized by electron-donating groups, polymerization will proceed by the S N 1 mechanism. [20] The cationic species is a heteroatom and the chain grows by the addition of cyclic monomers thereby opening the ...
Step-growth and chain-growth are the main classes of polymerization reaction mechanisms. The former is often easier to implement but requires precise control of stoichiometry. The latter more reliably affords high molecular-weight polymers, but only applies to certain monomers. A classification of the polymerization reactions
The pectin lyase is playing a crucial role in many biotechnological uses including the textile industry, paper manufacturing, wastewater pretreatment of pectin, clarifying of the juice, and extraction of oil. It has the ability to efficiently break the pectin molecule's back bone by β-eliminating in order to form pectin-oligosaccharide.
The kinetics and rates of step-growth polymerization can be described using a polyesterification mechanism. The simple esterification is an acid-catalyzed process in which protonation of the acid is followed by interaction with the alcohol to produce an ester and water. However, there are a few assumptions needed with this kinetic model.
The folding mechanism of PelC involves two slow phases that have been attributed to proline isomerization. Some of the proteins in this family are allergens . Allergies are hypersensitivity reactions of the immune system to specific substances called allergens (such as pollen, synthetic materials, dust, stings, drugs, or food) that, in most ...