Official Full Name
Pectate Lyase
Background
Pectate lyase (EC 4.2.2.2) is an enzyme involved in the maceration and soft rotting of plant tissue. Pectate lyase is responsible for the eliminative cleavage of pectate, yielding oligosaccharides with 4-deoxy-α-D-mann-4-enuronosyl groups at their non-reducing ends. The protein is maximally expressed late in pollen development. It has been suggested that the pollen expression of pectate lyase genes might relate to a requirement for pectin degradation during pollen tube growth. This enzyme belongs to the family of lyases, specifically those carbon-oxygen lyases acting on polysaccharides.
Synonyms
(1->4)-alpha-D-galacturonan lyase; polygalacturonic transeliminase; pectic acid transeliminase; polygalacturonate lyase; endopectin methyltranseliminase; pectate transeliminase; endogalacturonate transeliminase; pectic acid lyase; pectic lyase; alpha-1#4-D-endopolygalacturonic acid lyase; PGA lyase; PPase-N; endo-alpha-1#4-polygalacturonic acid lyase; polygalacturonic acid lyase; pectin trans-eliminase; Polygalacturonic acid trans-eliminase; Pectate lyase; EC 4.2.2.2
Pectin lyase (PL) is a kind of pectinase, which catalyzes the elimination and cleavage of pectin molecular chain, and is of great significance in the food processing industry to increase the yield of fruit juice. Pectin lyase (trans-elimination enzyme) is a kind of pectinase that cleaves pectin polymer by trans-elimination. Lyase breaks the glycosidic bond at C-4 position and eliminates an H from C-5 at the same time. The atom thus produces an unsaturated product.
Physical chemistry and biological characteristics
The molecular weight of most lyases is between 30 and 40 kDa, the optimum temperature is between 40 and 50 ℃, the optimum pH is between 7.5 and 10.0, and the isoelectric point is between 7.0 and 11.0. between. Two PMGLs produced by Aureobasidium pullulans LV-10, L1 and L2, have an optimum temperature of 40°C and an optimum pH value of 5.0 and 7.5, respectively. According to Singh et al. report, a heat-resistant exopolygalacturonase from Bacillus sp. has the highest enzyme activity at a pH of 11.0 and a temperature of 69°C. This enzyme requires Ca2+ participation. According to reports, the role of PGLs must involve the participation of Ca2+, so chelating agents such as EDTA are their inhibitors, and the role of PMGLs does not require the participation of cations, but the participation of Ca2+ or other cations can promote the reaction, and internal Polymethylgalacturonic acid lyase is the only enzyme that can cleave the α-1,4-glycosidic bond in highly esterified pectin without pretreatment by other enzymes.
Source
Polygalacturonic acid lyase (PGLs) can be produced by a variety of bacteria and some pathogenic fungi. Endo-galacturonic acid lyase is more abundant than exo-galacturonic acid lyase. PGLs can be isolated from bacteria and fungi in decaying food. According to reports, this enzyme can be isolated from strains such as Colletotrichum lindemutmionum and Bacteroides thetaiotaomicrom. In contrast, the products of polymethylgalacturonic acid lyase (PMGLs) are rarely reported. Only a few reports indicate that we can isolate such enzymes from strains such as Aspergillus japonicus and Penicillium paxilli.
Applications
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Juice extraction
The main application of pectinase in industry is for the extraction and clarification of fruit juice. If there is a pectin substance in the juice, the viscosity of the juice increases and becomes cloudy. Industrial production is to use a mixture of pectinase and amylase to clarify juice, which can shorten the filtration time by 50%.
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Wine making
With the improvement of living standards, people's consumption of fruit wine is also increasing. The role of pectinase in fruit wine production has also been recognized by more and more people in the industry. Adding pectinase in the production of fruit wine can improve the color of fruit wine products and have better sensory quality; can clarify fruit wine and make the product more stable; can increase the flavor of fruit wine and make the taste fuller.
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Applications in other industries
In recent years, in the textile industry, people have combined pectinase with amylase, lipase, cellulase, and hemicellulase to remove gums from cotton. This method replaces the previous method of using toxic and corrosive soda water. This method is safer and more beneficial to the ecological environment.
In the feed production industry, plant raw materials contain pectin, which is an anti-nutritional factor, which affects the utilization rate of feed. The addition of pectinase in feed can effectively degrade pectin, and can effectively promote the absorption of nutrients, thereby increasing the utilization rate of feed.
Reference
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Willems PJ.; et al. Fucosidosis revisited: a review of 77 patients. Am. J. Med. Genet. 1991, 38 (1): 111–31.