Escherichia coli dehalogenase catalyst

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Data waiving:

other justification

Justification for data waiving:

other:

Justification for type of information:

Acute Oral Toxicity
The E. coli strain used is BL21(DE3), a non-pathogenic laboratory strain widely used in academia and at large scale in industry for production of a wide range of biotechnology based products. E. coli is present in all mammals and is one of the first microorganisms to colonise the neonatal gut and remains in the gut in substantial quantities throughout life without exhibiting any adverse effects on the host. The adverse effects of pathogenic strains of E. coli are elicited through the presence of endotoxins, also known as lipopolysaccharides (component of the outer cell membrane), which possess specific antigens. Testing of the lipopolysaccharide obtained from E. coli BL21(DE3) for oral toxicity in mice has been carried out Harper. A single dose of endotoxin (lipopolysaccharide) from Escherichia coli BL21[DE3] was administered to groups of male and female CD-1 mice (n=5/group) at doses up to 1,000,000 endotoxin units (EU) per mouse by oral gavage. The mice were observed for mortality, body weight effects, and clinical signs for 14 days after which they were sacrificed for gross organ necropsy. All mice survived until the scheduled sacrifice, no clinical signs of toxicity were observed, no test substance-related body weight losses occurred and no gross lesions were present at necropsy. Under the conditions of this study, oral administration of E. coli BL21(DE3) endotoxin to mice at a dose of up to 1,000,000 EU/mouse produced no evidence of toxicity.
Reference
Harper MS, Carpenter C, Klocke DJ, Carlson G, Davis T, Delaney B. (2011). Food Chem. Toxicol. 49, (8), 1770-2