Difference between revisions of "Part:BBa K4224000"
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| − | <h1>Description</h1> | + | <h1>Description</h1> |
| − | <p>Enzyme beta-galactosidase | + | <p>Enzyme beta-galactosidase (lactase) (E.C. 3.2.1.23) catalyzes the hydrolysis of β (1–3) and β (1–4) galactosyl bonds in oligo- and disaccharides but it also catalyzes the reverse reaction of the hydrolysis, often called transglycosylation. Based on sequence homology, beta-galactosidases have been classified as members of GH1, GH2, GH35, and GH42 of the GH-A superfamily of glycoside hydrolase [13]. Beta-Galactosidase from Aspergillus oryzae (Ao-β-gal) belongs to GH 35 family. The amino acid sequence of Ao-β-gal includes 1005 residues with an average molecular mass of 110kDa [9].<br> |
| + | Beta-Galactosidase is mostly known for its ability to hydrolyze milk sugar lactose [1,2]. Lactose is a disaccharide and consists of one galactose and one glucose linked together with a β(1–4) bond. Hence, a common example of the industrial utilization of beta-galactosidase is the manufacture low-lactose or lactose-free dairy products. Aspergillus oryzae is one of the most widely-used fungal sources of commercial beta-galactosidase, as A. oryzae beta-galactosidase showed great advantages of extracellular expression with higher culture yield, less contaminated proteins, and easier downstream processing. <br> | ||
| + | The low-lactose or lactose-free dairy products are important to people who suffer from lactose intolerance. Since lactase hydrolyses lactose into glucose and galactose, when the expression of lactase declines due to genetic disorder or natural ageing, the amount of lactose people can tolerate will decrease. This results in lactose malabsorption which leads up to several symptoms, such abdominal pain, diarrhea and nausea. For humans, lactose intolerance is a world-wide problem. It is estimated that 70% of the world’s adult population suffers from different degrees of lactose intolerance [3]. To allow people with lactose intolerance to enjoy dairy products, our project aimed to express lacA in Pichia pastoris to produce lactose-free dairy products. | ||
| + | </p> | ||
| + | <h1>Protocols</h1> | ||
| + | <h2>Heterlogous expression in Pichia pastoris X33</h2> | ||
| + | <p></p> | ||
| + | <h2>Enzyme Properties</h2> | ||
Revision as of 17:29, 10 October 2022
Contents
Description
Enzyme beta-galactosidase (lactase) (E.C. 3.2.1.23) catalyzes the hydrolysis of β (1–3) and β (1–4) galactosyl bonds in oligo- and disaccharides but it also catalyzes the reverse reaction of the hydrolysis, often called transglycosylation. Based on sequence homology, beta-galactosidases have been classified as members of GH1, GH2, GH35, and GH42 of the GH-A superfamily of glycoside hydrolase [13]. Beta-Galactosidase from Aspergillus oryzae (Ao-β-gal) belongs to GH 35 family. The amino acid sequence of Ao-β-gal includes 1005 residues with an average molecular mass of 110kDa [9].
Beta-Galactosidase is mostly known for its ability to hydrolyze milk sugar lactose [1,2]. Lactose is a disaccharide and consists of one galactose and one glucose linked together with a β(1–4) bond. Hence, a common example of the industrial utilization of beta-galactosidase is the manufacture low-lactose or lactose-free dairy products. Aspergillus oryzae is one of the most widely-used fungal sources of commercial beta-galactosidase, as A. oryzae beta-galactosidase showed great advantages of extracellular expression with higher culture yield, less contaminated proteins, and easier downstream processing.
The low-lactose or lactose-free dairy products are important to people who suffer from lactose intolerance. Since lactase hydrolyses lactose into glucose and galactose, when the expression of lactase declines due to genetic disorder or natural ageing, the amount of lactose people can tolerate will decrease. This results in lactose malabsorption which leads up to several symptoms, such abdominal pain, diarrhea and nausea. For humans, lactose intolerance is a world-wide problem. It is estimated that 70% of the world’s adult population suffers from different degrees of lactose intolerance [3]. To allow people with lactose intolerance to enjoy dairy products, our project aimed to express lacA in Pichia pastoris to produce lactose-free dairy products.