关键词: 家蝇幼虫, 抗菌肽, 抗弓形虫, 速殖子, DNA含量

Abstract:

　　【Abstract】　Objective　To observe the injury of the antimicrobial peptides with anti-Toxoplasma activity isolated from housefly larvae on the DNA of T.gondii tachyzoites. Methods　The antimicrobial peptides of housefly larvae were induced largely by infection and injury, which were isolated and purified by trituration, centrifugalization and column chromatography. Then the antimicrobial peptides with anti-Toxoplasma activity were sieved by methyl thiazolyl tetrazolium colorimetric method and haemacytometry. The DNA contents of T.gondii tachyzoites were detected by flow cytometry （FCM）.  Results　From the bar chart of DNA contents, it showed that the difference of distribution between the control group and the experimental group, and tachyzoites in the experimental group were fewer than that in the control group. The tachyzoites in M1 phase were fewer than that in M2 phase in the control group, but the condition was on the contrary in the antimicrobial peptide group. Furthermore, the peak in the M1 stage had an obvious antedisplacement.  Conclusion　The antimicrobial peptide isolated from housefly larvae could kill T.gondii by inhibiting the synthesis of DNA.

Key words: Housefly larvae, Antimicrobial peptide, Anti-Toxoplasma, Tachyzoite, DNA content