CDX-403

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Justification for type of information:

In general, pure enzymes are not considered to be of concern (Collection of information on enzymes, European Commission, 2002). The main concerns arise from toxic by-products or contaminants of the fermentation process. This enzyme is produced by Escherichia coli BL21, an E.coli strain that is widely used for protein expression and that is fully sequenced. No products are produced by this strain that are known (or expected) to be mutagenic. Furthermore, there is an extensive database in place showing a lack of genotoxic effects with enzyme preparations produced in either bacterial and mammalian systems (Collection of information on enzymes, European Commission (2002)). Multiple in vitro mutagenicity studies have been performed using a variety of enzymes. Ames tests (28/28) and Chromosomal aberration studies (26/26) all tested negative (Pariza and Cook , Regulatory Toxicology and Pharmacology 56 (2010)). This also included enzymes produced by E. coli strains. The genotoxicity of several enzymes was also tested in the in vivo Mammalian Erythrocyte Micronucleus test . There were no positive findings in the conducted studies. Since there are no concerns for genotoxicity it is concluded that it is scientifically justified not to perform further genotoxicity studies.