Enzyme manufacturing protein stabilization

Since most synthetic applications require enzymes catalyzing nonnatural substrates, their properties often have to be improved. One way to achieve this is to optimize reaction conditions such as pH, temperature, solvents, additives, etc. [6-9]. Another way is to modulate the substrates without compromising the synthetic efficiency of the overall reaction [10]. In most cases for commercial manufacturing, however, the protein sequences have to be altered to enhance reactivity, stereoselectivity and stability. It was estimated that over 30 commercial enzymes worldwide have been engineered for industrial applications [11]. Precise prediction of which amino acids to mutate is difficult to achieve. Since the mid 1990s, directed evolution... 

Electrode surfaces modified with a multilayered surface architecture prepared by a layer-by-layer repeated deposition of several enzyme mono-layers show a modulated increase of surface-bound protein with a subsequent increase in output current, which is directly correlated with the number of deposited protein layers. The versatility of this approach allows alternate layers of different proteins for the manufacture of electrode surfaces, which are the basis for multianalyte sensing devices with multiple substrate specificities. The surface chemistry used for the manufacture of multilayered electrode surfaces is similar to that previously described for the preparation of affinity sensors, and is based on the stabilization of self-assembled multilayer assemblies by specific affinity interactions, electrostatic attraction, or covalent binding between adjacent monolayers. 

The use of a-transglucosidases in the large-scale manufacture of novel bioderivatives is stiU limited by several factors such as enzyme selectivity, stability, and, in some cases, efficiency. To overcome these Umitations and further enlarge the appUcatimis of these enzymes, the latest protein engineering technologies have been used to tailor biocatalysts with specific properties for novel oligosaccharide. 

Usually, and for obvious reasons, stability is discussed in terms of its benefits. Any such discussion would, however, be incomplete without some mention of commercial situations where stability is undesirable, or even dangerous. Enzymes are used in many food manufacturing processes, mainly in the form of lyases (amylases, phosphorylases, lipases, etc ). Health and safety considerations demand that they must have been removed entirely before the hnished products reach the marketplace. In a similar manner, any extraneous enzymes used as processing aids in protein purihcation protocols have to be removed prior to freeze-drying. 

---