About Beta-glucosidase / GBA:
Beta-glucosidases are found throughout natures, occurring in organisms from bacteria to highly-evolved mammals. Beta-glucosidases are an evolutionarily conserved feature of biology, kept for their powerful digestive qualities.
Beta-glucosidases Structure
Beta-glucosidases are not a single compound but a variety of chemical compounds that vary substantially in their tolerances from organism to organism. Their effect may be the same - to catalyse particular plant starches and turn them into sugar - but their properties are different.
GBA Interaction
Bacteria and archaea are not the only branches of the tree of life capable of creating glucosidase - so too are fungi. Evidence suggests that fungi are a rich source of thermostable beta-glucosidase and can be found in species including Aspergillus phoenicis and Sclerotium glucanicum. What is interesting about these fungi is that both grow in environments between 24 and 27 degrees celsius and yet their glucosidases reach optimal temperatures at between 60 and 75 degrees Celcius. The reasons why some fungi evolved such thermostable compounds is not yet known, but it could have something to do with making synthesis easier. In other words, it may be an accidental biological byproduct of another survival need.
Beta-glucosidase Mechanism
Researchers divide beta-glucosidases into three groups based on their substrate specificity. Different varieties of the enzyme have different effects on a variety of compounds with which they interact; Aryl-beta-glucosidases. Aryl-beta-glucosidases interact preferably with aryl-beta-glucosides, Cellobiases. Cellobiases have a preference for the hydrolysis of cell-oligosaccharides, such as cellobiose, Broad specificity beta-glucosidases, this particular form of the enzyme has hydrolytic activity on both aryl-beta-glucosides and cell-oligosaccharides, meaning that it can be used on a larger variety of substrates than either of the alternatives individually.
GBA Function
Glucosidase is an essential part of the hydrolysis of plant biomatter in the process of making alternative fuels, such as ethanol. When making ethanol, producers need to be able to access the ethanol-producing potential of the cellulose contained in the plant cell wall. Cellulose is sometimes difficult to break down, but with the assistance of a variety of enzymes, manufacturers can reduce it to glucose, which can then be fermented into ethanol-based products.
Breaking down cellulose requires a series of steps. Converting lignocellulosic biomass into glucose is a complex chemical reaction. First, it is necessary to pretreat the biomass to increase the efficiency of the subsequent reaction. Cellulose hydrolysis requires the presence of cellobiohydrolases, endo-beta-1,4-glucanases and, of course, beta-glucosidases. The synergistic activity of all of these enzymes together transforms cellobiose into glucose, providing manufacturers with the raw materials that they need to create ethanol.