Product description
Invertase, also known as sucrose invertase (Invertase, E.C.3.2.1.26), catalyzes the breakdown of sucrose into fructose and glucose in sucrose metabolism and is one of the key enzymes in sucrose metabolism in higher plants. Based on the optimal pH values, sucrose invertases are divided into acid invertase (AI) and neutral invertase (NI), with many reports considering neutral invertase to be the same as alkaline invertase. AI has an optimal pH of 3.0 to 5.0 and is divided into soluble AI (S-AI) and cell wall insoluble AI (B-AI: cell-wall binding acid invertase). The former is distributed in the vacuoles or the free space of cells, while the latter exists in the cells and is bound to the cell wall. B-AI is mainly involved in the breakdown of sucrose during the unloading of the phloem apoplast, maintaining the concentration of sucrose between the sink and source. B-AI catalyzes the degradation of sucrose to produce reducing sugars, which then react with 3,5-dinitrosalicylic acid to form a brown-red amine compound with characteristic light absorption at 540nm. The rate of increase in light absorption at 540nm within a certain range is proportional to the activity of B-AI.
Additional Materials and Equipments Required
Visible spectrophotometer, 1mL glass cuvette (light path 1cm), low-temperature centrifuge, water bath, pipette, mortar and pestle, ice, and distilled water.