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Studies have shown that fungal laccase is a multi-copper oxidase that can deliver 4 copper ions at the same time, so it can catalyze a variety of phenolic compounds and aromatic compounds. Based on its wide range of substrates, laccase has become a useful biocatalyst in the application of biotechnology, especially in the field of bioremediation, including the degradation of lignin, the decolorization of synthetic dye wastewater, and the degradation and detoxification of environmental pollutants. However, the laccase secreted by wild strains is limited in yield and difficult to purify, on the other hand, its activity is susceptible to environmental factors. In recent years, microbial fermentation engineering has gradually emerged, and the fermentation production of most laccases mainly stays at the level of shake flasks and fermentation tanks. Ryan et al. used an air-lift fermentor to ferment Trametes villus, and the laccase activity in the fermentation broth could reach 11.8 U/ml. At this stage, although the production and application of some fungal laccases can be realized by using the fermentation process, the culture conditions of microorganisms such as temperature, pH, humidity, and the length of the fermentation cycle will affect the production of laccase during the fermentation process. Therefore, most laccases are fermented The process only stays at the laboratory scale. Based on the above shortcomings, it is very important to develop an efficient, low-cost, and environmentally friendly method for producing laccase. | Studies have shown that fungal laccase is a multi-copper oxidase that can deliver 4 copper ions at the same time, so it can catalyze a variety of phenolic compounds and aromatic compounds. Based on its wide range of substrates, laccase has become a useful biocatalyst in the application of biotechnology, especially in the field of bioremediation, including the degradation of lignin, the decolorization of synthetic dye wastewater, and the degradation and detoxification of environmental pollutants. However, the laccase secreted by wild strains is limited in yield and difficult to purify, on the other hand, its activity is susceptible to environmental factors. In recent years, microbial fermentation engineering has gradually emerged, and the fermentation production of most laccases mainly stays at the level of shake flasks and fermentation tanks. Ryan et al. used an air-lift fermentor to ferment Trametes villus, and the laccase activity in the fermentation broth could reach 11.8 U/ml. At this stage, although the production and application of some fungal laccases can be realized by using the fermentation process, the culture conditions of microorganisms such as temperature, pH, humidity, and the length of the fermentation cycle will affect the production of laccase during the fermentation process. Therefore, most laccases are fermented The process only stays at the laboratory scale. Based on the above shortcomings, it is very important to develop an efficient, low-cost, and environmentally friendly method for producing laccase. | ||
| − | At this stage, researchers have used molecular biology methods to heterologously express laccase genes on the basis of overcoming many shortcomings of traditional laccase purification processes and fermentation processes, in order to obtain laccase with higher yield and enzymatic activity. At present, according to production requirements, laccases from different sources have been successfully expressed in various host cells such as bacteria, fungi, and insect rod cells. At present, in industrial applications, fungal cells such as Pichia pastoris, Saccharomyces cerevisiae and Kluyveromyces lactis dominate the heterologous expression process of laccase. These fungal cells have the following advantages in the application process: first, high-density fermentation can increase the production of laccase, second, the engineered strain has higher enzyme activity after modification, and third, most fungal host cells have been confirmed to be directly used by humans | + | At this stage, researchers have used molecular biology methods to heterologously express laccase genes on the basis of overcoming many shortcomings of traditional laccase purification processes and fermentation processes, in order to obtain laccase with higher yield and enzymatic activity. At present, according to production requirements, laccases from different sources have been successfully expressed in various host cells such as bacteria, fungi, and insect rod cells. At present, in industrial applications, fungal cells such as Pichia pastoris, Saccharomyces cerevisiae and Kluyveromyces lactis dominate the heterologous expression process of laccase. These fungal cells have the following advantages in the application process: first, high-density fermentation can increase the production of laccase, second, the engineered strain has higher enzyme activity after modification, and third, most fungal host cells have been confirmed to be directly used by humans edible. |
In recent years, with the deepening of research, scientists have found that laccase also has many shortcomings in fungal heterologous expression. When the engineered strain is fermented, it is found that the fermentation cycle is longer and usually takes about one week, and the strain culture consumes a lot. In their research, Maestre et al. found that host yeast can inactivate laccase by interfering with the glycosylation metabolism of laccase. Laccase-producing bacteria from the same source often have multiple laccase genes at the same time, and the existence of these genes ultimately leads to a more complex and diverse isozyme system of laccase. Therefore, when the researchers performed heterologous expression of these isoenzymes, they found that not all fungal expression systems can maximize the productivity of laccase, and the laccase activity produced by heterologous expression in yeast cells is far less than that of wild-type laccase. Strains are also susceptible to factors such as pH. Compared with wild strains, the half-life of laccase in some expression systems has also changed. Comprehensive analysis of the heterologous expression of laccase in fungi, the bacterial expression system has been gradually applied to the direction of heterologous expression of laccase due to its easy operation, short culture period, and strong reproductive ability. | In recent years, with the deepening of research, scientists have found that laccase also has many shortcomings in fungal heterologous expression. When the engineered strain is fermented, it is found that the fermentation cycle is longer and usually takes about one week, and the strain culture consumes a lot. In their research, Maestre et al. found that host yeast can inactivate laccase by interfering with the glycosylation metabolism of laccase. Laccase-producing bacteria from the same source often have multiple laccase genes at the same time, and the existence of these genes ultimately leads to a more complex and diverse isozyme system of laccase. Therefore, when the researchers performed heterologous expression of these isoenzymes, they found that not all fungal expression systems can maximize the productivity of laccase, and the laccase activity produced by heterologous expression in yeast cells is far less than that of wild-type laccase. Strains are also susceptible to factors such as pH. Compared with wild strains, the half-life of laccase in some expression systems has also changed. Comprehensive analysis of the heterologous expression of laccase in fungi, the bacterial expression system has been gradually applied to the direction of heterologous expression of laccase due to its easy operation, short culture period, and strong reproductive ability. | ||
Revision as of 08:10, 15 October 2021
laccase
Degrading antibiotics
Sequence and Features
- 10COMPATIBLE WITH RFC[10]
- 12INCOMPATIBLE WITH RFC[12]Illegal NheI site found at 73
- 21INCOMPATIBLE WITH RFC[21]Illegal BglII site found at 782
- 23COMPATIBLE WITH RFC[23]
- 25INCOMPATIBLE WITH RFC[25]Illegal NgoMIV site found at 1230
Illegal NgoMIV site found at 1596
Illegal AgeI site found at 193 - 1000COMPATIBLE WITH RFC[1000]
Profile
Origin: Pleurotus ostreatus（P. ostreatus HAUCC 162）
Properties: Degradation of sulfadiazine
Usage and Biology
Laccase is an oxidoreductase that uses oxygen as an electron acceptor. It can oxidize a variety of aromatic compounds and produce water as a by-product. In the 19th century, humans first discovered laccase in Japanese sumac. Because of its outstanding application value in biotechnology applications, scientists have gradually deepened their research on laccase. They discovered that laccase is also present in animals and microorganisms. Laccases derived from different hosts have different functions in the body. Among them, fungal laccases derived from white rot fungi, Trametes, Pleurotus ostreatus and other fungal laccases occupy the mainstream of the current laccase application process. This type of laccase has a relatively wide range of substrate specificity during the application process, and does not require hydrogen peroxide. With the participation of, a variety of phenolic compounds and their derivatives can be directly oxidized with oxygen as the electron acceptor.
In recent years, the main methods for removing antibiotic residues from different sources are traditional methods such as high-temperature composting, fermentation; oxidation, adsorption, electrochemical treatment, membrane method, and microbial degradation. However, these methods have the disadvantages of low removal efficiency, high cost of use, and the possibility of secondary pollution to the environment. Moreover, these methods cannot fundamentally solve the problem of antibiotic residues in poultry. Therefore, it is necessary to find a direct, effective and low-cost method to remove antibiotic residues in poultry. At present, many studies have shown that fungal laccase plays an important role in the process of treating antibiotic residues in wastewater. Three laccase-producing genes LACC6, LACC9, and LACC10 obtained from Pleurotus ostreatus were heterologously expressed in Pichia pastoris and found that the efficiency of degrading sulfa antibiotics reached more than 97%.
Heterologous expression and application advantages of fungal laccase
Studies have shown that fungal laccase is a multi-copper oxidase that can deliver 4 copper ions at the same time, so it can catalyze a variety of phenolic compounds and aromatic compounds. Based on its wide range of substrates, laccase has become a useful biocatalyst in the application of biotechnology, especially in the field of bioremediation, including the degradation of lignin, the decolorization of synthetic dye wastewater, and the degradation and detoxification of environmental pollutants. However, the laccase secreted by wild strains is limited in yield and difficult to purify, on the other hand, its activity is susceptible to environmental factors. In recent years, microbial fermentation engineering has gradually emerged, and the fermentation production of most laccases mainly stays at the level of shake flasks and fermentation tanks. Ryan et al. used an air-lift fermentor to ferment Trametes villus, and the laccase activity in the fermentation broth could reach 11.8 U/ml. At this stage, although the production and application of some fungal laccases can be realized by using the fermentation process, the culture conditions of microorganisms such as temperature, pH, humidity, and the length of the fermentation cycle will affect the production of laccase during the fermentation process. Therefore, most laccases are fermented The process only stays at the laboratory scale. Based on the above shortcomings, it is very important to develop an efficient, low-cost, and environmentally friendly method for producing laccase.
At this stage, researchers have used molecular biology methods to heterologously express laccase genes on the basis of overcoming many shortcomings of traditional laccase purification processes and fermentation processes, in order to obtain laccase with higher yield and enzymatic activity. At present, according to production requirements, laccases from different sources have been successfully expressed in various host cells such as bacteria, fungi, and insect rod cells. At present, in industrial applications, fungal cells such as Pichia pastoris, Saccharomyces cerevisiae and Kluyveromyces lactis dominate the heterologous expression process of laccase. These fungal cells have the following advantages in the application process: first, high-density fermentation can increase the production of laccase, second, the engineered strain has higher enzyme activity after modification, and third, most fungal host cells have been confirmed to be directly used by humans edible.
In recent years, with the deepening of research, scientists have found that laccase also has many shortcomings in fungal heterologous expression. When the engineered strain is fermented, it is found that the fermentation cycle is longer and usually takes about one week, and the strain culture consumes a lot. In their research, Maestre et al. found that host yeast can inactivate laccase by interfering with the glycosylation metabolism of laccase. Laccase-producing bacteria from the same source often have multiple laccase genes at the same time, and the existence of these genes ultimately leads to a more complex and diverse isozyme system of laccase. Therefore, when the researchers performed heterologous expression of these isoenzymes, they found that not all fungal expression systems can maximize the productivity of laccase, and the laccase activity produced by heterologous expression in yeast cells is far less than that of wild-type laccase. Strains are also susceptible to factors such as pH. Compared with wild strains, the half-life of laccase in some expression systems has also changed. Comprehensive analysis of the heterologous expression of laccase in fungi, the bacterial expression system has been gradually applied to the direction of heterologous expression of laccase due to its easy operation, short culture period, and strong reproductive ability.