Affiliations 

  • 1 Programa de Pós-Graduação em Inovação Terapêutica, Universidade Federal de Pernambuco, 50670-901 Recife, PE, Brazil; Laboratório de Biodispositivos Nanoestruturados, Departamento de Bioquímica, Universidade Federal de Pernambuco, 50670-901 Recife, PE, Brazil
  • 2 Centro de Ciências da Saúde, Departamento de Medicina Tropical, Universidade Federal de Pernambuco, 50670-901 Recife, PE, Brazil
  • 3 S-Inova Biotech, Programa de Pos-Graduação em Biotecnologia, Universidade Católica Dom Bosco, 79117-900 Campo Grande, MS, Brazil
  • 4 Programa de Pós-Graduação em Inovação Terapêutica, Universidade Federal de Pernambuco, 50670-901 Recife, PE, Brazil; Laboratório de Biodispositivos Nanoestruturados, Departamento de Bioquímica, Universidade Federal de Pernambuco, 50670-901 Recife, PE, Brazil. Electronic address: csrandrade@gmail.com
J Pharm Biomed Anal, 2022 Jul 15;216:114788.
PMID: 35525110 DOI: 10.1016/j.jpba.2022.114788

Abstract

Bacterial and fungal infections are challenging due to their low susceptibility and resistance to antimicrobial drugs. For this reason, antimicrobial peptides (AMP) emerge as excellent alternatives to overcome these problems. At the same time, their active insertion into the cell wall of microorganisms can be availed for biorecognition applications in biosensing platforms. Temporin-PTA (T-PTA) is an AMP found in the skin secretions of the Malaysian fire frog Hylarana picturata, which presents antibacterial activity against MRSA, Escherichia coli, and Bacillus subtilis. In this work, T-PTA was explored as an innovative sensing layer aiming for the electrochemical differentiation of Klebsiella pneumoniae, Acinetobacter baumannii, Bacillus subtilis, Enterococcus faecalis, Candida albicans, and C. tropicalis based on the structural differences of their membranes. The biosensor was analyzed through electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). In this approach, the different structural features of each microorganism resulted in different adherence degrees and, therefore, different electrochemical responses. The transducing layer was fabricated by the self-assembling of a 4-mercaptobenzoic acid (MBA) monolayer and gold-capped magnetic nanoparticles (Fe3O4@Au) implemented to improve the electrical signal of the biointeraction. We found that each interaction, expressed in variations of electron transfer resistance and anodic peak current, demonstrated a singular response from which the platform can discriminate all different microorganisms. We found expressive sensitivity towards Gram-negative species, especially K. pneumoniae. A detection limit of 101 CFU.mL-1 and a linear range of 101 to 105 CFU.mL-1 were obtained. The T-PTA biosensor platform is a promising and effective tool for microbial identification.

* Title and MeSH Headings from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.