Enzyme Activity Measurement for Glycosylases

Creative Enzymes has been recognized as a leader of enzyme activity assays. Our ability to test various glycosylases with high accuracy and reproducibility has been endorsed by tens of thousands of customers in the past several years. Based on the up-to-date enzymology knowledge, we have developed innovative and specific tests for many enzymes that are unique only through our services. With the dedicated scientist team and most advanced facility, we will stay as the top choice of glycosylase activity measurement.

Glycosylases (EC 3.2) are a class of hydrolases that remove glycosyl groups from the substrate via hydrolysis reactions. The glycosylase enzymes are extremely important to many biological processes and ubiquitous in all human tissues. Glycosylases are essential for cell functions, signaling, and metabolism. The critical roles of glycosylases can be demonstrated by the fact that more than 50% of all human proteins are glycoproteins. Besides, ribose and deoxyribose are the building blocks of nucleic acid and deoxynucleic acid, the carriers of genetic information. As even more commonly known, carbohydrates, also known as sugars or polysaccharides, are the main material for both energy storage and structure composition in a living organism. Therefore, the importance of glycosylases cannot be overemphasized. Based on the catalytic activity, glycosylases can be classified into two group: glycosidases (EC 3.2.1) are the glycosylases that hydrolyze O- and S-glycosyl substrates; and DNA glycosylases (EC 3.2.2) are the enzymes that hydrolyze N-glycosyl groups.

Glycosidases, also called glycoside hydrolases or glycosyl hydrolases, catalyze the hydrolysis of glycosidic bonds. In prokaryotes, the enzymes are heavily involved in nutrient uptake, functioning in both intracellular and extracellular environments. In eukaryotes, Glycosidases are located in the endoplasmic reticulum and Golgi apparatus as the key to biosynthesis of glycoproteins. In addition, they serve as the catalyst in the lysosome to degrade carbohydrate structures, a common component of membranes and supporting materials. In the digestive tract, glycosidases help to breakdown complex carbohydrates such as lactose and starch to facilitate energy and nutrition intake. Due to multiple significant functions, glycosidases are found useful in many areas. They are employed to treat proteins and antibodies for desired glycosylation modifications. The strict substrate specificity is utilized to characterize and analyze the composition of glycoprotein and polysaccharide, and the information is used in molecular and biological drug development. Industrial applications include biomass degradation, pulp and paper bleaching, fabric care, and synthesis of complex carbohydrate structures. Based on sequence similarity, glycosidases can be sorted into 128 glycoside hydrolase families (GH1 to GH128), or 14 clans based on the tertiary structure.

DNA glycosylases catalyze the cleavage of N-glycosidic bond, specifically cutting the nitrogenous base from the ribose-phosphate moiety of nucleic acids. They are largely involved in base excision repair, a primary mechanism to repair DNA with small lesions. Some DNA glycosylases only express the slycosylase activity, and thus are called monofunctional DNA glycosylases. Whereas other glycosylases display additional apurinic/apyrimidinic (AP) lyase activity and are called bifunctional glycosylases. Based on structural similarity, DNA glycosylases can be grouped into four superfamilies: UDG, AAG, MutM/Fpg, and HhH-GPD families. The UDG (uracil-DNA glycosylase) family is most studied in molecular biology, due to its important function in revert the DNA damages caused by common deamination of cytosine to uracil. Since DNA glycosylases directly work on DNA molecules, malfunction of the enzymes are highly related to caner. For example, downregulation of DNA glycosylases are found to lead to occurrence of specific cancers. However, the research area is relatively new and little information has been collected to direct treatment of cancer.

Although studies on glycosylases have rapidly grown in the past few years, characterization, especially reliable activity measurement of the enzymes, has not been widely demonstrated. First, due to substrate specificity, substrates of some glycosylases are difficult to prepare. Also, most substrates of glycosylases are carbohydrates that do not have particular spectrometric properties and thus not suitable for spectrometric analysis. As the expert of enzymology and carbohydrate chemistry, Creative Enzymes has established and developed activity assays for most glycosylases. We are able to provide various natural and synthetic substrates, some of which are unique in the market. In addition, we are able to perform spectrophotometric assays using labelled substrates or activity measurement through other analysis including chromatographic and fluorometric analysis. Our enzyme assay platforms allows us to determine enzyme activity accurately in various reaction matrices and under a variety of conditions. The specific test protocol, however, could be distinctive from one measurement to another. Therefore, we strongly encourage you to share as many details as possible when you submit the service request. Our professional enzymologist team will design the most suitable assays based on your need.

Glycosidases (EC 3.2.1) are the glycosylases that hydrolyze O- and S-glycosyl substrates.

DNA glycosylases (EC 3.2.2) are the enzymes that hydrolyze N-glycosyl groups.