Interaction of LL-37 with Model Membrane Systems and Preparing Lipid Based Biosensor for the Detection of LL-37

• Main Authors: An-Ting Cheng, 鄭安婷
• Other Authors: Chung-Yih Wang
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/76077186069867131972

碩士 === 大同大學 === 生物工程學系(所) === 97 === It’s well known that bacteria have ability to develop antibiotic-resistance in short time after treatment. To find therapeutic agents with different mode of action than conventional antibiotics is a necessity. To meet the above requirement, antimicrobial peptides (AMPs) represent a good alternative for infective antibiotics. AMP LL-37 with positive charges belongs to an immune system that has a capacity to distinguish membrane from different lipids in human. This special property makes LL-37 destroy the negative charged bacteria membranes. Therefore the above mechanism is effective to drug resistance bacteria. Normally bacteria and LL-37 will not exist in urine, except for those patients who suffer urinary tract infection (UTI). Hopefully, a screening biosensor can be made by using the above character. DSC (Differential Scanning Calorimeter) was used to measure interaction between LL-37 and liposome that plays a biomembrane role. The stability of the complex can be affected by adding interference salt and urea. In the meantime, the change of liposome structure can be observed by a fluorescence probe on it. Finally, the biosensor was made by immobilizing liposomes on silane coated surface. Testing was made by mixing the sample containing LL-37 on the biosensor plate. The content of LL-37 can be detected and determined by impedance and phase angle variations.