scholarly journals Bacteriomimetic Liposomes Improve Antibiotic Activity of a Novel Energy-Coupling Factor Transporter Inhibitor

Pharmaceutics ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 4
Author(s):  
Menka Drost ◽  
Eleonora Diamanti ◽  
Kathrin Fuhrmann ◽  
Adriely Goes ◽  
Atanaz Shams ◽  
...  
Keyword(s):  
Model Organism ◽  
Energy Coupling ◽  
Coupling Factor ◽  
Free Drug ◽  
Drug Formulation ◽  
Phosphatidylcholine Liposomes ◽  
Loading Method ◽  
Fold Reduction ◽  
Hydrophobic Compound ◽  
Bacterial Growth Inhibition

Liposomes have been studied for decades as nanoparticulate drug delivery systems for cytostatics, and more recently, for antibiotics. Such nanoantibiotics show improved antibacterial efficacy compared to the free drug and can be effective despite bacterial recalcitrance. In this work, we present a loading method of bacteriomimetic liposomes for a novel, hydrophobic compound (HIPS5031) inhibiting energy-coupling factor transporters (ECF transporters), an underexplored antimicrobial target. The liposomes were composed of DOPG (18:1 (Δ9-cis) phosphatidylglycerol) and CL (cardiolipin), resembling the cell membrane of Gram-positive Staphylococcus aureus and Streptococcus pneumoniae, and enriched with cholesterol (Chol). The size and polydispersity of the DOPG/CL/± Chol liposomes remained stable over 8 weeks when stored at 4 °C. Loading of the ECF transporter inhibitor was achieved by thin film hydration and led to a high encapsulation efficiency of 33.19% ± 9.5% into the DOPG/CL/Chol liposomes compared to the phosphatidylcholine liposomes (DMPC/DPPC). Bacterial growth inhibition assays on the model organism Bacillus subtilis revealed liposomal HIPS5031 as superior to the free drug, showing a 3.5-fold reduction in CFU/mL at a concentration of 9.64 µM. Liposomal HIPS5031 was also shown to reduce B. subtilis biofilm. Our findings present an explorative basis for bacteriomimetic liposomes as a strategy against drug-resistant pathogens by surpassing the drug-formulation barriers of innovative, yet unfavorably hydrophobic, antibiotics.

Discovery of Antibacterial Agents Inhibiting the Energy-Coupling Factor (ECF) Transporters by Structure-Based Virtual Screening

2020 ◽  
Author(s):  
Eleonora Diamanti ◽  
Inda Setyawati ◽  
Spyridon Bousis ◽  
leticia mojas ◽  
lotteke Swier ◽  
...  
Keyword(s):  
Virtual Screening ◽  
Antibacterial Agents ◽  
Antimicrobial Agents ◽  
Energy Coupling ◽  
Coupling Factor ◽  
Design Synthesis ◽  
Screening Design ◽  
Starting Point ◽  
Wide Range ◽  
Vitamin Uptake

Here, we report on the virtual screening, design, synthesis and structure–activity relationships (SARs) of the first class of selective, antibacterial agents against the energy-coupling factor (ECF) transporters. The ECF transporters are a family of transmembrane proteins involved in the uptake of vitamins in a wide range of bacteria. Inhibition of the activity of these proteins could reduce the viability of pathogens that depend on vitamin uptake. Because of their central role in the metabolism of bacteria and their absence in humans, ECF transporters are novel potential antimicrobial targets to tackle infection. The hit compound’s metabolic and plasma stability, the potency (20, MIC Streptococcus pneumoniae = 2 µg/mL), the absence of cytotoxicity and a lack of resistance development under the conditions tested here suggest that this scaffold may represent a promising starting point for the development of novel antimicrobial agents with an unprecedented mechanism of action.<br>

scholarly journals A Novel Heme Transporter from the Energy Coupling Factor Family Is Vital for Group A Streptococcus Colonization and Infections

2020 ◽  
Vol 202 (14) ◽  
Author(s):  
Nilanjana Chatterjee ◽  
Laura C. C. Cook ◽  
Kristin V. Lyles ◽  
Hong Anh T. Nguyen ◽  
Darius J. Devlin ◽  
...  
Keyword(s):  
Inductively Coupled Plasma ◽  
Group A Streptococcus ◽  
Bacterial Colonization ◽  
Critical Role ◽  
Systemic Infection ◽  
Energy Coupling ◽  
Coupling Factor ◽  
Iron Complex ◽  
Invasive Infection ◽  
Group A

ABSTRACT Group A streptococcus (GAS) produces millions of infections worldwide, including mild mucosal infections, postinfection sequelae, and life-threatening invasive diseases. During infection, GAS readily acquires nutritional iron from host heme and hemoproteins. Here, we identified a new heme importer, named SiaFGH, and investigated its role in GAS pathophysiology. The SiaFGH proteins belong to a group of transporters with an unknown ligand from the recently described family of energy coupling factors (ECFs). A siaFGH deletion mutant exhibited high streptonigrin resistance compared to the parental strain, suggesting that iron ions or an iron complex is the likely ligand. Iron uptake and inductively coupled plasma mass spectrometry (ICP-MS) studies showed that the loss of siaFGH did not impact GAS import of ferric or ferrous iron, but the mutant was impaired in using hemoglobin iron for growth. Analysis of cells growing on hemoglobin iron revealed a substantial decrease in the cellular heme content in the mutant compared to the complemented strain. The induction of the siaFGH genes in trans resulted in the induction of heme uptake. The siaFGH mutant exhibited a significant impairment in murine models of mucosal colonization and systemic infection. Together, the data show that SiaFGH is a new type of heme importer that is key for GAS use of host hemoproteins and that this system is imperative for bacterial colonization and invasive infection. IMPORTANCE ECF systems are new transporters that take up various vitamins, cobalt, or nickel with a high affinity. Here, we establish the GAS SiaFGH proteins as a new ECF module that imports heme and demonstrate its importance in virulence. SiaFGH is the first heme ECF system described in bacteria. We identified homologous systems in the genomes of related pathogens from the Firmicutes phylum. Notably, GAS and other pathogens that use a SiaFGH-type importer rely on host hemoproteins for a source of iron during infection. Hence, recognizing the function of this noncanonical ABC transporter in heme acquisition and the critical role that it plays in disease has broad implications.

scholarly journals Design and synthesis of thiamine analogues to study their binding to the ECF transporter for thiamine in bacteria

MedChemComm ◽  
2016 ◽  
Vol 7 (5) ◽  
pp. 966-971 ◽  
Author(s):  
L. Monjas ◽  
L. J. Y. M. Swier ◽  
A. R. de Voogd ◽  
R. C. Oudshoorn ◽  
A. K. H. Hirsch ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Substrate Specificity ◽  
Small Molecules ◽  
Energy Coupling ◽  
Coupling Factor ◽  
Design And Synthesis ◽  
Further Development ◽  
Thiamine Analogues

This work presents new small molecules that bind to the protein ThiT, which confers substrate specificity to the Energy-Coupling Factor (ECF) transporter for thiamine. Further development of the molecules may lead to compounds with antimicrobial activity.

scholarly journals Two Essential Arginine Residues in the T Components of Energy-Coupling Factor Transporters

2009 ◽  
Vol 191 (21) ◽  
pp. 6482-6488 ◽  
Author(s):  
Olivia Neubauer ◽  
Anja Alfandega ◽  
Janna Schoknecht ◽  
Ulrich Sternberg ◽  
Anne Pohlmann ◽  
...  
Keyword(s):  
Atpase Activity ◽  
Transmembrane Protein ◽  
Energy Coupling ◽  
Coupling Factor ◽  
Single Mutation ◽  
Modular Assembly ◽  
Double Mutation ◽  
Arginine Residues ◽  
Uptake Activity ◽  
Vitamin Uptake

ABSTRACT Energy-coupling factor (ECF) transporters, a recently discovered class of importers of micronutrients, are composed of a substrate-specific transmembrane component (S component) and a conserved energy-coupling module consisting of a transmembrane protein (T component) and pairs of ABC ATPases (A proteins). Based on utilization of a dedicated (subclass I) or shared (subclass II) energy-coupling module, ECF systems fall into two subclasses. The T components are the least-characterized proteins of ECF importers, and their function is essentially unknown. Using RcBioN and LmEcfT, the T units of the subclass I biotin transporter (RcBioMNY) of a gram-negative bacterium and of the subclass II folate, pantothenate, and riboflavin transporters of a lactic acid bacterium, respectively, we analyzed the role of two strongly conserved short motifs, each containing an arginine residue. Individual replacement of the two Arg residues in RcBioN reduced ATPase activity, an indicator of the transporter function, by two-thirds without affecting the modular assembly of the RcBioMNY complex. A double Arg-to-Glu replacement destroyed the complex and abolished ATPase activity. The corresponding single mutation in motif II of LmEcfT, as well as a double mutation, led to loss of the T unit from the subclass II ECF transporters and inactivated these systems. A single Arg-to-Glu replacement in motif I, however, abolished vitamin uptake activity without affecting assembly of the modules. Our results indicate that the conserved motif I in T components is essential for intramolecular signaling and, in cooperation with motif II, for subunit assembly of modular ECF transporters.

scholarly journals Staphylococcus lugdunensis: a Skin Commensal with Invasive Pathogenic Potential

2020 ◽  
Vol 34 (2) ◽  
pp. e00205-20
Author(s):  
Simon Heilbronner ◽  
Timothy J. Foster
Keyword(s):  
Membrane Damage ◽  
Energy Coupling ◽  
Coupling Factor ◽  
Coagulase Negative Staphylococcus ◽  
Peptide Antibiotic ◽  
Staphylococcus Lugdunensis ◽  
Pathogenic Potential ◽  
Content Type ◽  
Flight Mass Spectrometry ◽  
Von Willebrand

SUMMARYStaphylococcus lugdunensis is a species of coagulase-negative staphylococcus (CoNS) that causes serious infections in humans akin to those of S. aureus. It was often misidentified as S. aureus, but this has been rectified by recent routine use of matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) in diagnostic laboratories. It encodes a diverse array of virulence factors for adhesion, cytotoxicity, and innate immune evasion, but these are less diverse than those encoded by S. aureus. It expresses an iron-regulated surface determinant (Isd) system combined with a novel energy-coupling factor (ECF) mechanism for extracting heme from hemoproteins. Small cytolytic S. lugdunensis synergistic hemolysins (SLUSH), peptides related to phenol-soluble modulins of S. aureus, act synergistically with β-toxin to lyse erythrocytes. S. lugdunensis expresses a novel peptide antibiotic, lugdunin, that can influence the nasal and skin microbiota. Endovascular infections are initiated by bacterial adherence to fibrinogen promoted by a homologue of Staphylococcus aureus clumping factor A and to von Willebrand factor on damaged endothelium by an uncharacterized mechanism. S. lugdunensis survives within mature phagolysosomes of macrophages without growing and is released only following apoptosis. This differs fundamentally from S. aureus, which actively grows and expresses bicomponent leukotoxins that cause membrane damage and could contribute to survival in the infected host. S. lugdunensis is being investigated as a probiotic to eradicate S. aureus from the nares of carriers. However, this is contraindicated by its innate virulence. Studies to obtain a deeper understanding of S. lugdunensis colonization, virulence, and microbiome interactions are therefore warranted.

Crystal structure of a folate energy-coupling factor transporter from Lactobacillus brevis

Nature ◽  
2013 ◽  
Vol 497 (7448) ◽  
pp. 268-271 ◽  
Author(s):  
Ke Xu ◽  
Minhua Zhang ◽  
Qin Zhao ◽  
Fang Yu ◽  
Hui Guo ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Lactobacillus Brevis ◽  
Energy Coupling ◽  
Coupling Factor

scholarly journals The action of tributyltin on energy coupling in coupling-factor-deficient submitochondrial particles

1975 ◽  
Vol 152 (2) ◽  
pp. 333-339 ◽  
Author(s):  
Alan P. Dawson ◽  
Michael J. Selwyn
Keyword(s):  
Binding Sites ◽  
Adenosine Triphosphatase ◽  
Respiratory Control ◽  
Energy Coupling ◽  
Coupling Factor ◽  
Small Extent ◽  
Submitochondrial Particles ◽  
Succinate Oxidation ◽  
The Relationship ◽  
Protein Permeability

1. Tributyltin at concentrations of approx. 1nmol/mg of protein induces respiratory control and lessens the protein permeability of coupling-factor-deficient submitochondrial particles. 2. At these concentrations or lower, it increases the P/O ratio of the particles to a small extent and inhibits the adenosine triphosphatase activity without greatly increasing its sensitivity to uncoupling agents. 3. It fails to stimulate ATP-driven reversed electron transport or transhydrogenase, but stimulates the transhydrogenase driven by aerobic succinate oxidation. 4. The results indicate that, unlike oligomycin, tributyltin does not discriminate between damaged and intact ATP-synthesizing complexes. 5. The relationship between the oligomycin- and tributyltin-binding sites is discussed.

Sign in / Sign up

Export Citation Format

Share Document