Table 1.

A compilation of all seventeen recombinant GCase enzymes expressed plus Cerezyme (Genzyme Corp) derived from patient infusion bags. Enzymes are listed in order of specific activity given as units enzyme per mg recombinant protein. One U is defined as the amount of enzyme to release 1 nmol 4-methylumbelliferone per hour. Except for the three enzymes that were not appropriately expressed, expression levels were found to be approximately bimodal where a select group of enzymes were expressed at a low level with final yields of 10 μg/mL or less. Other recombinant GCase enzymes were typically purified at yields several fold higher. Specific activity values represent the average of all preparations of each listed enzyme where proteins were expressed for 48–96 h and not concentrated before purification.

Summary of recombinant GCase activity and expression level
GCase	Specific activity (U/mg)	Expression level
Cerezyme	1.25E+05	N/A
RDP-GCase	3.67E +04	Acceptable
Tat-GCase	3.32E+04	Acceptable
Tat-GCase-GFP-Tet1	3.26E+04	Low
Tat-5xTet1-GCase-GFP	2.79E+04	Low
RDP-Rigid-GCase	2.53E+04	Acceptable
RDP-Flex-GCase	2.46E+04	Acceptable
RDP-IgAh-GCase	2.43E+04	Acceptable
RDP-Tat-GCase	2.24E+04	Acceptable
GCase (Fishman Lab)	2.04E+04	Low
Tat-Tet1-GCase-GFP	1.81E+04	Acceptable
Tat-GCase-GFP	1.76E+04	Acceptable
RDP-GCase-GFP	1.53E+04	Acceptable
Tet1-GCase-GFP	1.23E+04	Low
TTC-GCase-GFP	8.18E+03	Acceptable
Tat-TTC-GCase-GFP	N/A	Expressed in truncated form
RDP-GFP-GCase	N/A	Expressed in truncated form
Tat-GCase-GFP-5xTet1	N/A	Not expressed