Enzyme commercialization

Enzyme Commercial acetylcholinesterase preparation - electrical organ acetone powder (extract) from electric eel (Electrophorus electricus) (Sigma, E2384) was used. 

Ketoreductases identified by numbers refer to enzymes commercially available from Codexis (Pasadena, CA -formerly Biocatalytics) and those with CDX prefixes refer to enzymes obtained under license from Codexis (Redwood City, CA -Codex KRED Panel v 1.0). 

Figure 2. Efficiency of an rDNA approach to enzyme commercialization. Areas in boxes refer to the typical times required for Identification, Scale-up and Commercialization. Efficiencies are recognized in Identification of enzymes (protein engineering) and shortened Scale-up times (generic hosts).

The following protocol describes the activation of avidin or streptavidin with sulfo-SMCC and its subsequent conjugation with an enzyme modified to contain sulfhydryls using SATA (Chapter 1, Section 4.1). A method for the opposite approach, wherein the enzyme is activated with SMCC and the avidin component is thiolated, is presented immediately after this protocol. This strategy may be the most common approach to forming these conjugates (Fig. 363). In addition, since there are enzymes commercially available that are preactivated with SMCC (Pierce), their use may be the easiest solution. 

The examples presented in this chapter demonstrate that a combination of various analytical approaches and the selection of suitable model systems can add valuable information to our knowledge about pathways and enzymes involved in the biosynthesis of chiral volatiles. Some of the techniques need further improvement, e.g. by use of radioactively labeled precursors the detection threshold of metabolites can be lowered significantly addition of precursors in concentrations comparable to those in natural plant or microbial systems would be possible. The investigation of the enantioselectivity of enzymes has to be emphasized, eventually not only enzymes commercially available or easily accessible in microorganisms but also those active in plant systems have to be studied. 

For each class of enzymes introduced in Chapter 4.5, Table 7.2 shows the most important current commercial application areas. In 1995 the world sales of industrial enzymes were estimated to be about 1.2 billion. By far the most important enzymes commercially are (isolated) hydrolases. Over 90% of enzyme sales is generated by hydrolases such as proteases, lipases and (hemi)cellulases, which are typically used in bulk applications such as detergent formulations, food feed, and in the treatment of pulp paper. Next are isomerases and lyases, and clearly emerging are the oxidoreductases. At the moment, the world leader is NOVO Nordisk in Denmark, followed by the US-based company... 

Enzymes from various sources have been used for asymmetric reductions in organic synthesis. Microorganisms are the most important sources. There are a huge number of species (mostly in soil), containing a variety of enzymes. Commercially available microbial dehydrogenases are alcohol dehydrogenases from yeast, Ther-moanaerobium brockii (TBADH), and the hydroxysteroid dehydrogenase from Pseudomonas testosteroni. 

Keratinase M-Zyme, A proteolytic enzyme, commercially produced by a strain of Streptomyces fradiae Nickerson, Noval, U.S. pat. 2,988,487 (1961 to Rutgers Res, and Educ. Found.). Can convert about 50% of ihe dry wt of wool into a water-sol form, permitting hair separation from hides. The amount of enzyme needed to dehair hides is not enough to cause much digestion of the hair itself, which is recovered and used in felt making. The enzyme attacks at the base of the hair shaft, which is particularly sensitive to the action of keratinase. 

All four means of immobilization have been used successfully in laboratory operation. Machinery has been developed for large-scale production of microcapsules with various contents. Chemical procedures have been described for covalent bonding of enzyme to carrier. It has been reported (Anon, 1970) that Tanabe Seiyakii Co., Osaka, is now using immobilized enzymes commercially to catalyze the hydrolysis step in the production of D or L amino acids. It has also been reported (Takasaki et al., 1969) that glucose isomerase can be retained... 

Another problem is the units used for detailing the amount of enzyme used for these biotransformations. Quantities are often given in units (U), but this is rarely accompanied by a definition of what a unit represents and this value changes between different enzymes, commercial sources and grades of purification. This is an issue that may obscure the use of glycosidases in the synthetic laboratory but the uninitiated should not be discouraged. 

Table 2.2. Numbers of enzymes identified and numbers of enzymes commercially available...

Enzyme Commercially Available Customer has Freedom to Operate... 

Enzyme Commercially Available Enzyme is Proprietary to the Vendor In this situation, the vendor becomes responsible for all aspects of enzyme manufacture and formulation. If the enzyme of interest is one that is already being manufactured at very large scales for other industries, as is the case for many commodity enzymes (e.g., for commercial detergents), these can often be pircchased at very lorv cost. Enzymes offered solely for biocatalysis applications are usually more expensive. The main issue in both cases is that there is usually only a single supplier for the enzyme. 

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