The present work describes the synthesis of hybrid dipeptides H-Lys-Gpn-PEA, C1; H-Lys-β^3,3A_C6C-PEA, C2, and THPA conjugated dipeptides, THPA-Lys-Gpn-PEA, C3, and THPA-Lys-β^3,3A_C6C-PEA, C4. All the peptides were evaluated against both Gram-negative and Gram-positive bacterial strains. Among all, peptide C4 exhibited the most potent activity with MIC 1.56 μM against P. aeruginosa (MTCC 424) and S. aureus (MTCC 737). Further, time-kill kinetics, fluorescence assays, and scanning electron microscopy (SEM) studies were performed in order to understand the mechanism of action and efficacy of peptide C4, The fluorescence assays and SEM images demonstrated the bacterial killing through membrane disruption. The peptide C4 exhibited very low hemolytic activity with negligible cytotoxicity against normal human breast cell line FR2.

目前的工作描述了杂合二肽 H-Lys-Gpn-PEA, C1的合成；H-Lys-β ^3,3 A _C6C - PEA、C2和 THPA 共轭二肽、THPA-Lys-Gpn-PEA、C3和 THPA-Lys-β ^3,3 A _C6C -PEA 、C4。针对革兰氏阴性和革兰氏阳性细菌菌株评估所有肽。其中，肽C4表现出最有效的活性，对铜绿假单胞菌(MTCC 424) 和金黄色葡萄球菌的MIC 为 1.56 μM(MTCC 737)。此外，为了了解肽C4的作用机制和功效，进行了时间杀伤动力学、荧光测定和扫描电子显微镜 (SEM) 研究。荧光测定和 SEM 图像证明了通过膜破裂杀死细菌。肽C4表现出非常低的溶血活性，对正常人乳腺细胞系 FR2 的细胞毒性可忽略不计。