A rationally designed synthetic antimicrobial peptide against Pseudomonas-associated corneal keratitis: Structure-function correlation

• Published in: Biophysical chemistry Vol. 286; p. 106802
• Main Authors: Mohid, Sk Abdul, Sharma, Prerana, Alghalayini, Amani, Saini, Tripti, Datta, Debarun, Willcox, Mark D.P., Ali, Haydar, Raha, Sreyan, Singha, Achintya, Lee, DongKuk, Sahoo, Nirakar, Cranfield, Charles G., Roy, Sanhita, Bhunia, Anirban
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.07.2022
• Subjects: Anti-Bacterial Agents - pharmacology; Anti-Infective Agents; Antimicrobial peptide (AMP); Antimicrobial Peptides; Bacterial keratitis; Contact lens; Eye Infections, Bacterial - drug therapy; Eye Infections, Bacterial - microbiology; Humans; Keratitis - drug therapy; Keratitis - metabolism; Keratitis - microbiology; Nuclear magnetic resonance (NMR); Pseudomonas; Pseudomonas aeruginosa; trNOESY; ALS; TOCSY; MTT; LPS; POPE; POPG; CFU; OD; Antimicrobial peptide (AMP); MIC99; Pseudomonas aeruginosa; CHAPSO; AMP; Contact lens; NOE; GUV; LUV; Bacterial keratitis; TSP; NMR; ROS; HCEC; PI; ITC; NOESY; HSQC; Nuclear magnetic resonance (NMR)
• ISSN: 0301-4622; 1873-4200
• DOI: 10.1016/j.bpc.2022.106802

Contact lens wearers are at an increased risk of developing Pseudomonas-associated corneal keratitis, which can lead to a host of serious ocular complications. Despite the use of topical antibiotics, ocular infections remain a major clinical problem, and a strategy to avoid Pseudomonas-associated microbial keratitis is urgently required. The hybrid peptide VR18 (VARGWGRKCPLFGKNKSR) was designed to have enhanced antimicrobial properties in the fight against Pseudomonas-induced microbial keratitis, including contact lens-related keratitis. In this paper, VR18's modes of action against Pseudomonas membranes were shown by live cell Raman spectroscopy, live cell NMR, live-cell fluorescence microscopy and measures taken using sparsely tethered bilayer lipid membrane bacterial models to be via a bacterial-specific membrane disruption mechanism. The high affinity and selectivity of the peptide were then demonstrated using in vivo, in vitro and ex vivo models of Pseudomonas infection. The extensive data presented in this work suggests that topical employment of the VR18 peptide would be a potent therapeutic agent for the prevention or remedy of Pseudomonas-associated microbial keratitis. Corneal infections upon contact lens wear are a major health concern and a tough challenge for the eye care practitioners. Currently, there is no other alternative to topical antibiotic therapy or daily disposable lens except for corneal transplantation. Here, we report the topical employ of non-toxic and non-hemolytic VR18 as a powerful therapeutic agent for the prevention or remedy of Pseudomonas-associated microbial keratitis. [Display omitted] •A hybrid antimicrobial peptide VR18 has high potency against Pseudomonas aeruginosa clinical isolates.•VR18 peptide showed low toxicity to human derived HCEC cells.•The biophysical analysis and the dynamics of the VR18 peptide indicate membrane specificity towards the microbial membrane over the mammalian membrane.•We have tested the modes of action of VR18 using live-cell NMR, Raman spectroscopy and sparsely tethered bilayer lipid membranes.•VR18 has the potential to be used clinically for the treatment and prevention of corneal keratitis.