New Peptide-Based Antimicrobials for Tackling Drug Resistance in Bacteria: Single-Cell Fluorescence Imaging

Abstract

New peptide molecules with metal binding abilities proved to be active against multidrug resistant clinical isolates. One of them labeled with a dansylated lysine has been imaged inside single-multidrug resistant bacteria cells by deep ultraviolet fluorescence, showing a heterogeneous subcellular localization. The fluorescence intensity is clearly related to the accumulation of the drug inside the bacteria, being dependent both on its concentration and on the incubation time with cells.

Optical Biosensing of Bacteria and Bacterial Communities

“…Selectivity is most frequently achieved through use of recognition elements, such as antibodies, enzymes and affinity reagents. Due to their inherent simplicity, affinity reagents, including antibodies [27, 31, 35–37], aptamers [30, 38–42], siderophores [29, 43], bacteriophages [32, 44, 45], antimicrobials [46, 47], and lectins [48], are commonly used. Among recognition agents, antibody–antigen recognition is most frequently used because of its high affinity (attractive K d values) and specificity.…”

“…Synthetic fluorophores have been engineered to have tunable excitation and emission, high quantum efficiency, good photostability, and excellent specificity when conjugated to a recognition element. With recent advances in the engineering of fluorophores, a wide range of biomolecular phenomena can be studied with all of the inherent advantages of fluorescence, especially the sensitivity and background discrimination that make it possible to visualize spatial structure [91] and to detect single molecules and/or bacteria [26, 47, 92–97]. …”

Peptide-mediated vectorization of metal complexes: conjugation strategies and biomedical applications

“…For instance, Artaud and cowokers described the synthesis of metallopeptides by anchoring a tris(2-pyridylmethyl)amine (tpa) or a 2,2′-dipicolylamine (dpa) ligand to a resin-bound peptide followed by cleavage and metallation with a Zn(II), a Co(III) or a Cu(II) salt ( Figure 1c). 35,36 The peptides used in this study were the short antimicrobial peptide analogue RWRW-OBn and the efflux pump modulator PAβN. Recently, it has been reported the synthesis of Zn(II) and Cu(II) metallopeptides based on PyTACN and (S,S')-BPBP tetradentate aminopyridine ligands in the context of ROS generation in cancer therapies (Figure 1d).…”

Phytochemical Complexes Towards Solving Multi-Drug Resistance: An Overview

“…The steady decrease in the discovery of new antibiotics and commercialization after the 1980s while at the same the serious threat of microbial multi-drug resistance continues to prevail, an example is the increasing occurrence of Methicillin-resistant Staphylococcus aureus (MRSA) over the same period among others [6,7]. On the other hand, is the concern over acquired drug resistance and serious sideeffects of current anti-cancer drugs with rising cases of cancer, breast cancer especially is one of the leading causes of death worldwide, this is one more important reason to develop better antimicrobial alternatives [4,8].…”