Creative Enzymes stands out in the marketplace with specific, customizable activity assays developed in house. We work together with our customers through our process to solve specific problems, mirror their processes, and develop new enzyme activity quantification methods. Our aim is to lower the cost of enzyme assays so that they are accessible to all researchers. Ultimately, the high quality and lost cost set us apart from other competitors. Herein, we are proud to offer the reliable enzymatic assay for ADP-specific glucokinase.

ATP plays diversified roles in the storage of free energy in biological systems. Moreover, ATP also acts as a phosphoryl donor in kinase reactions. ATP-dependent hexokinase catalyzes the phosphorylation of glucose, using ATP as a phosphoryl donor. All known ATP-dependent hexokinases isolated from a wide range of organisms, such as human, yeast, and Schistosoma mansoni, are highly related. ADP-specific glucokinases have been shown to catalyze glucose phosphorylation using ADP as the phosphoryl donor. ADP-specific glucokinases are constructed as homodimeric (Pyrococcus furiosus) or monomeric (Thermococcus litoralis) proteins, and are highly specific for ADP and glucose.

The presence of ADP-specific kinases bring two main benefits to a living system: one is that ADP shows higher thermostability than ATP, especially in the presence of divalent cations (such as Mg²⁺, Ca²⁺, and Zn²⁺); the other is that anabolic reactions producing ADP offer a substrate for ADP-dependent kinases and enhancement of the activation of sugars under low energy charge conditions. ADP-specific glucokinases and phosphofructokinases from a hyperthermophilic archaon were found to be homologous, forming a novel group of kinases. Because no other kinases that use ADP are known to date, this novel kinase group is a very rare model that can shed light on the evolutionary origin of kinases. Therefore, these enzymes are attracting an ever-increasing interest for being used in the study of enzymatic evolution.

Because of the specificity of this enzyme itself, activity assays of ADP-specific glucokinases using spectrophotometric assays have not been well established in an industrial scale. However, the spectrophotometric assay is demonstrated to be the most reliable and cost-effective method for activity quantification of this enzyme. Fortunately, Creative Enzymes is confident in offering the most advanced spectrophotometric instruments to measure the enzymatic activity accurately for ADP-specific glucokinase. For example, ADP-specific glucokinase is measured by a coupled assay with yeast glucose-6-phosphate dehydrogenase measuring the formation of NADPH. The assay is performed at 50 °C. At this temperature, the yeast enzyme remains active, and ADP-specific glucokinase is sufficiently active to measure its activity. The absorbance of NADPH is followed at 334 nm.

Creative Enzymes is a global leader in the development, optimization, and supply of bioanalytical services and enzymatic assays for the customers. Our prompt service, best customer care, and dedicated approaches have made us the most preferred vendor to our competitors.

Figure: The crystal structure of ADP-specific glucokinase from T. litoralis.
PDB: 4B8R