คุณสมบัติของโปรตีน Shrimp Ovarian Peritrophin domain A (SOP-A) ในการยับยั้งจุลินทรีย์

Abstract

Shrimp ovarian peritrophin (SOP), a major protein in jelly layer and cortical rods, plays a role in egg protection after spawning. Previous study, sequence of SOP gene from Fenneropenaeus merguiensis (Fm-SOP) was composed of domain A and domain B. The SOP domain A contains amino acid sequences between 1-80 of Fm-SOP. The domain A had six conserved cysteines which may inhibit microorganism. The molecular weight of purified SOP-A protein was about 9 kDa. Antimicrobial activity of SOP-A protein was investigate by liquid growth inhibition assay. Minimal Inhibition Concentration (MIC) of SOP-A with Staphylococcus aureus, Escherichia coli, Vibrio harveyi, Candida albicans and Fusarium oxysporum were 0.035 mg/ml, 0.28 mg/ml, 0.28 mg/ml, 0.57 mg/ml and 0.015 mg/ml, respectively. The SOP-A protein was able to agglutinate V. harveyi in vitro and displayed a chitinase activity. Moreover, the SOP-A protein also displayed proteinase inhibitory activity against trypsin. In addition the stability of SOP-A protein was tested and found decrease antimicrobial activity after incubation at 50 °C for 5 h.