Antibacterial activity of Eisenia fetida andrei coelomic fluid: Specificity of the induced activity

Adult earthworms Eisenia fetida andrei were found to increase their naturally occurring humoral bacteriostatic activity as a response to bacteria injection. Only the two earthworm pathogenic bacteria we tested, Bacillus megaterium (Gram-positive) and Aeromonas hydrophila (Gramnegative), induced this effect. In contrast, injecting earthworms with nonpathogenic bacteria, such as Acinetobacter sp. and Escherichia coli, as well as with sheep and human O erythrocytes or saline and sterile bacteria culture medium, did not modify the normal activity. When induced, the activity did not discriminate between the two pathogenic bacteria.