Do Earthworms Possess Antibacterial Properties?

 
A NEW ANTIBACTERIAL VERMIPEPTIDES FAMILY FROM EARTHWORM ESENIA FETIDA

Summary

2006

By Zhenjun Sun *, Yanqin Liu, Xichun Zhang, Chong Wang, Guozhen XU
College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100094, China

By using a simple and effective method of earthworm peptide inducement, separation and purification we established in our laboratory and achieved the patent in 2004, five antibacterial peptides (EP1 to EP5) were isolated and purified from earthworm tissue homogenate liquid and coelomic fluid in this research, which contained 5-7 amino acids with the same or similar amino acids sequence Ala-Met-Val-Ser-Gly, was named the antibacterial vermipeptides family (AVPF) according with the structure characteristic of these antibacterial peptides. The resistance of EP2 and EP3 to MGC803 cell was found in this research. The AVPF exist wide antibacterial speciality, for example of EP3, the results of anti-tumor activity of EP3 were that: EP3 could cause apoptosis of HeLa cell. The apoptotic activity was dose dependent. And the threshold value of EP3 to cause apoptotic on HeLa cell was 0.75mg/mL, with an apoptotic rate of 48.12%. The mechanism of antiviral activity of EP3 was inhibiting the duplicate of virus DNA.

AVPF concentrations and activities varied with the relation between the variation of survival environmental and the activity change of antibacterial peptides. In this research, we used environmental factors induced antibacterial peptides, compared with methods both damage inducement (shearing-off) and no damage stimulates (the treatment of shake and heavy metal). Results showed the biology and electricity induced method was the effective induction to the production of earthworm antibacterial peptides. The ecology mechanism principle of induction expression to the earthworm antibacterial peptide named trigger theory was proposed firstly in the research. The results from this paper and our former researches provided the foundation of earthworm’s ecology adaptation to the stressing environment and proved the theoretical hypothesis that peptides may be the antibacterial component in the antibacterial system of earthworm coelomic fluid.