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bioRxiv · 10.1101/2023.11.23.568446

A Novel AI-Designed Antimicrobial Peptide Synergistically Potentiates Aminoglycosides against Colistin- and Carbapenem-Resistant Acinetobacter baumannii

Capalash, N.·Thakur, V.·Gupta, V.·Sharma, P.·Gupta, A.
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Abstract

The urgent necessity for new antibiotics becomes glaringly evident with the relentless rise of multidrug-resistant (MDR) Acinetobacter baumannii in clinical environments, where its infections lead to alarmingly high mortality rates. Antimicrobial peptides (AMPs) represent a promising novel option to combat nosocomial infections caused by MDR A. baumannii. In this study, six novel synthetic peptides were designed through generative artificial intelligence (AI) and synthesized for further experiments. Peptides AIG-R1, AIG-R4, and AIG-R5 showed potent broad-spectrum antibacterial activity against Gram positive and Gram negative pathogens. One of the peptides, AIG-R5, was effective even against colistin and carbapenem-resistant strains of A. baumannii, prevented biofilm formation, and eradicated established biofilms by 60%. Notably, AIG-R5 enhanced the activity of different antibiotics and was found to exhibit synergistic activity with antibiotics from the Aminoglycoside class. The combination of AIG-R5 and Tobramycin at 1/8xMIC and 1/4xMIC effectively reduced pre-formed biofilms of carbapenem resistant A. baumannii more than either component alone, as documented by confocal laser scanning microscopy (CLSM). Significant dose reduction and negligible cytotoxicity exhibited by AIG-R5 with aminoglycosides further encourages evaluation of the combinations therapeutic potential in vivo against MDR A. baumannii infections.

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Capalash, N., Thakur, V., Gupta, V., Sharma, P., Gupta, A.. 2023-11-23. A Novel AI-Designed Antimicrobial Peptide Synergistically Potentiates Aminoglycosides against Colistin- and Carbapenem-Resistant Acinetobacter baumannii. https://doi.org/10.1101/2023.11.23.568446

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