Abstract
A silkworm cocoon contains several antimicrobial proteins such as protease inhibitors and seroins to provide protection for the enclosed pupa. In this study, we identified a new Bombyx mori phosphatidylethanolamine-binding protein (BmPEBP) with antimicrobial activity in the cocoon silk using semi-quantitative and quantitative RT-PCR, western blotting, and immunofluorescence. The results indicated that BmPEBP was synthesized in the middle silk gland and secreted into the sericin layer of the cocoon silk. Functional analysis showed that BmPEBP could inhibit the spore growth of four types of fungi, Candida albicans, Saccharomyces cerevisiae, Beauveriabassiana, and Aspergillus fumigates, by binding to the fungal cell membrane. Investigation of the interaction of BmPEBP with membrane phospholipids revealed that the protein showed a strong binding affinity to phosphatidylethanolamine, weak affinity to phosphatidylinositol, and no affinity to phosphatidylserine or phosphatidylcholine. Circular dichroism spectroscopy showed that binding to phosphatidylethanolamine caused conformational changes in the BmPEBP molecule by reducing β-sheet formation and inducing the appearance of an α-helix motif. We speculate that BmPEBP performs antifungal function in the cocoon silk through interaction with phosphatidylethanolamine in the fungal membrane.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: International Journal of Biological Macromolecules
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
