Glycopeptide Antibiotic Teicoplanin Research Articles

In Vivo Efficacy of a Nanoconjugated Glycopeptide Antibiotic in Silkworm Larvae Infected by Staphylococcus aureus

To contrast the rapid spread of antibiotic resistance in bacteria, new alternative therapeutic options are urgently needed. The use of nanoparticles as carriers for clinically relevant antibiotics represents a promising solution to potentiate their efficacy. In this study, we used Bombyx mori larvae for the first time as an animal model for testing a nanoconjugated glycopeptide antibiotic (teicoplanin) against Staphylococcus aureus infection. B. mori larvae might thus replace the use of mammalian models for preclinical tests, in agreement with the European Parliament Directive 2010/63/EU. The curative effect of teicoplanin (a last resort antibiotic against Gram-positive bacterial pathogens) conjugated to iron oxide nanoparticles was assessed by monitoring the survival rate of the larvae and some immunological markers (i.e., hemocyte viability, phenoloxidase system activation, and lysozyme activity). Human physiological conditions of infection were reproduced by performing the experiments at 37 °C. In this condition, nanoconjugated teicoplanin cured the bacterial infection at the same antibiotic concentration of the free counterpart, blocking the insect immune response without causing mortality of silkworm larvae. These results demonstrate the value and robustness of the silkworm as an infection model for testing the in vivo efficacy of nanoconjugated antimicrobial molecules.

Improvement of the conjugation transfer of N. gerenzanensis based on the synergistic effect of quorum sensing and antibiotic interference

Nonomuraea gerenzanensis (N. gerenzanensis) is known for its ability to biosynthesize A40926, the precursor of the glycopeptide antibiotic (GPA) Dalbavancin. However, challenges and uncertainties related to the genetic manipulation of the rare actinomycetes remain. In order to improve the conjugation transfer of N. gerenzanensis, the crucial factors affecting conjugal transfer were evaluated, including agar medium, mycelial state, donor-recipient ratio, magnesium ion concentration, and antibiotic coverage time firstly. Additionally, γ-butyrolactone (GBL) for quorum sensing (QS) and antibiotics targeting bacterial walls were applied to evaluate their effects on conjugation transfer. As a result, the optimal conditions of 5%TSB of liquid medium, 24 h of the period time, V0.1 of agar medium, 30 mM of magnesium ion, the ratio 10:1 of donor-to-recipient, and 27 h of the overlaying time of antibiotic were determined. Furthermore, the results showed that autoinducer GBL and GPA teicoplanin had a synergetic effect on the conjugation transfer of N. gerenzanensis at a working concentration of 60 µM and 0.5 µg mL−1, respectively. The highest conjugation efficiency could reach about 1.3 depending on the optimal process conditions and the interference of QS and antibiotics.

Increased incidence of teicoplanin-non-susceptible Staphylococcus epidermidis strains: a 6-year retrospective study

Glycopeptide antibiotics (vancomycin and teicoplanin) are usually used for the treatment of Staphylococcus epidermidis infections owing to their increased oxacillin resistance. However, S. epidermidis strains with decreased susceptibility to teicoplanin have become increasingly incident in recent years. We aimed to identify the characteristics of teicoplanin-non-susceptible (Teico-NS) S. epidermidis isolated at our hospital and analyze its relationship with teicoplanin usage. We retrospectively evaluated 328 S. epidermidis strains isolated from clinical isolates between January 2016 and December 2021. All strains were susceptible to vancomycin (minimal inhibitory concentration (MIC) ≤ 4 mg/L). The annual incidence for S. epidermidis strains with an elevated teicoplanin MIC of 8 mg/L ranged from 22.2 to 28.9%. In addition, in 2021, the number of S. epidermidis strains with teicoplanin MIC ≥ 16 mg/L rapidly increased (n = 13, 32.5%). Furthermore, teicoplanin use increased annually until 2019; however, in 2020, it decreased abruptly due to the COVID 19 pandemic. Thus, we could not confirm the existence of a clear correlation between teicoplanin usage and increased incidence of S. epidermidis with reduced teicoplanin-susceptibility. We showed the increased incidence of Teico-NS S. epidermidis in recent years. Further studies are needed to identify the mechanisms and risk factors for teicoplanin-resistance in S. epidermidis.

Glycopeptide Antibiotics Impair Neutrophil Effector Functions

Introduction: Neutrophilic granulocytes represent the first line of defense against microorganisms. Granulocytes phagocytose microorganisms and specifically synthesize oxygen radicals against them, which eventually kills the invaders. Methods: Neutrophilic granulocytes were isolated from peripheral blood of healthy volunteer donors. Putative interference of new-generation antibiotics with neutrophil function was tested using a collection of granulocyte-stimulating agents and Amplex™ Red-based plate assay and flow cytometry-based respiratory burst assays. In addition, phagocytosis of E. coli, IL-8 production, bactericidal activity, and CD62L expression of granulocytes were evaluated. Results: Of note, we found that the two glycopeptide antibiotics dalbavancin and teicoplanin inhibited ROS production upon granulocyte activation via different signaling pathways in a dose-dependent manner. Dalbavancin also blocked the PMA-induced shedding of CD62L. In contrast, the oxazolidinone antibiotics tedizolid and linezolid had no effect on neutrophil function, while the combination of ceftazidime/avibactam dose dependently inhibited the fMLP/Cytochalasin B-induced granulocyte burst in a dose-dependent manner. Additionally, we showed that dalbavancin and teicoplanin as well as sulfametrole/trimethoprim and ceftazidime/avibactam inhibited baseline and PMA-induced IL-8 production by neutrophilic granulocytes. Moreover, dalbavancin impaired the bactericidal activity of neutrophilic granulocytes. Conclusion: We here identified hitherto unknown inhibitory effects of several classes of antibiotics on the effector functions of neutrophilic granulocytes.

Differential Study of Antimicrobial Activity of Vancomycin and Teicoplanin (Targocid) against Strains of Staphylococcus aureus and Streptococci sp.

The glycopeptide antibiotics vancomycin and teicoplanin (targocid) are widely used in the treatment of infections caused by gram positive bacteria. Vancomyc inhibits both transglycosylation and transpeptidation reaction during peptidoglycan assembly, targocid inhibits peptidoglycan polymerization, resulting in inhibition of bacterial cell wall synthesis and cell death. In this study twenty strains of streptococcus pyogenes and streptococcus pneumoniae and twenty five strains of staphylococcus aureus were collected from different infections. MI Cs and MBCs of vancomycin and targocid were determined against the bacterial strains, the MICs of vancomycin for the streptococcus strains were 4-8 µg /ml compared with 8-16 µg/ml for targocid and MI Cs of targocid for staphylococcus aureus were 4-16 µg/ml MBC for the same strains were 8-32 µg/ml. the conclusion of this study was that targocid was less active than vancomycin against staphylococci but equal or more active against streptococci specifically it presents excellent in vitro activity against streptococcus pneumonia strains.

Self-association of the glycopeptide antibiotic teicoplanin A2 in aqueous solution studied by molecular hydrodynamics

The natural glycopeptide antibiotic teicoplanin is used for the treatment of serious Gram-positive related bacterial infections and can be administered intravenously, intramuscularly, topically (ocular infections), or orally. It has also been considered for targeting viral infection by SARS-CoV-2. The hydrodynamic properties of teicoplanin A2 (M1 = 1880 g/mol) were examined in phosphate chloride buffer (pH 6.8, I = 0.10 M) using sedimentation velocity and sedimentation equilibrium in the analytical ultracentrifuge together with capillary (rolling ball) viscometry. In the concentration range, 0–10 mg/mL teicoplanin A2 was found to self-associate plateauing > 1 mg/mL to give a molar mass of (35,400 ± 1000) g/mol corresponding to ~ (19 ± 1) mers, with a sedimentation coefficient s20, w = ~ 4.65 S. The intrinsic viscosity [eta] was found to be (3.2 ± 0.1) mL/g: both this, the value for s20,w and the hydrodynamic radius from dynamic light scattering are consistent with a globular macromolecular assembly, with a swelling ratio through dynamic hydration processes of ~ 2.

Teicoplanin derivatives block spike protein mediated viral entry as pan-SARS-CoV-2 inhibitors

The rapid emergence of highly transmissible SARS-CoV-2 variants poses serious threat to the efficacy of vaccines and neutralizing antibodies. Thus, there is an urgent need to develop new and effective inhibitors against SARS-CoV-2 and future outbreaks. Here, we have identified a series of glycopeptide antibiotics teicoplanin derivatives that bind to the SARS-CoV-2 spike (S) protein, interrupt its interaction with ACE2 receptor and selectively inhibit viral entry mediated by S protein. Computation modeling predicts that these compounds interact with the residues in the receptor binding domain. More importantly, these teicoplanin derivatives inhibit the entry of both pseudotyped SARS-CoV-2 Delta and Omicron variants. Our study demonstrates the feasibility of developing small molecule entry inhibitors by targeting the interaction of viral S protein and ACE2. Together, considering the proven safety and pharmacokinetics of teicoplanin as a glycopeptide antibiotic, the teicoplanin derivatives hold great promise of being repurposed as pan-SARS-CoV-2 inhibitors.

Glycopeptide Antibiotic Teicoplanin Inhibits Cell Entry of SARS-CoV-2 by Suppressing the Proteolytic Activity of Cathepsin L.

Since the outbreak of the coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), public health worldwide has been greatly threatened. The development of an effective treatment for this infection is crucial and urgent but is hampered by the incomplete understanding of the viral infection mechanisms and the lack of specific antiviral agents. We previously reported that teicoplanin, a glycopeptide antibiotic that has been commonly used in the clinic to treat bacterial infection, significantly restrained the cell entry of Ebola virus, SARS-CoV, and MERS-CoV by specifically inhibiting the activity of cathepsin L (CTSL). Here, we found that the cleavage sites of CTSL on the spike proteins of SARS-CoV-2 were highly conserved among all the variants. The treatment with teicoplanin suppressed the proteolytic activity of CTSL on spike and prevented the cellular infection of different pseudotyped SARS-CoV-2 viruses. Teicoplanin potently prevented the entry of SARS-CoV-2 into the cellular cytoplasm with an IC50 of 2.038 μM for the Wuhan-Hu-1 reference strain and an IC50 of 2.116 μM for the SARS-CoV-2 (D614G) variant. The pre-treatment of teicoplanin also prevented SARS-CoV-2 infection in hACE2 mice. In summary, our data reveal that CTSL is required for both SARS-CoV-2 and SARS-CoV infection and demonstrate the therapeutic potential of teicoplanin for universal anti-CoVs intervention.

The First Dimeric Derivatives of the Glycopeptide Antibiotic Teicoplanin.

Various dimeric derivatives of the glycopeptide antibiotic teicoplanin were prepared with the aim of increasing the activity of the parent compound against glycopeptide-resistant bacteria, primarily vancomycin-resistant enterococci. Starting from teicoplanin, four covalent dimers were prepared in two orientations, using an α,ω-bis-isothiocyanate linker. Formation of a dimeric cobalt coordination complex of an N-terminal L-histidyl derivative of teicoplanin pseudoaglycone has been detected and its antibacterial activity evaluated. The Co(III)-induced dimerization of the histidyl derivative was demonstrated by DOSY experiments. Both the covalent and the complex dimeric derivatives showed high activity against VanA teicoplanin-resistant enterococci, but their activity against other tested bacterial strains did not exceed that of the monomeric compounds.

Chiral analysis of selected enantiomeric drugs relevant in doping controls

Various substances classified by the World Anti-Doping Agency (WADA) as prohibited in sports feature one or more chiral centers. Amongst those, few analytes exist that are so-called threshold substances, for which also enantiomerically pure drugs are available. The commonly employed non-chiral analysis of these compounds does not allow for differentiating between the use of a racemic mixture of e.g. salbutamol and formoterol from their enantiomerically pure analogs. In order to support identifying the exclusive use of the pharmacologically active compound, a multi-analyte chiral chromatography-based analytical approach was developed. The test method considering the β2-agonists fenoterol, formoterol, and salbutamol, the stimulant methamphetamine, the anabolic agent clenbuterol, and the β-blockers metoprolol, pindolol, and propranolol was based on liquid chromatography with a chiral column comprising a stationary phase based on the macrocyclic glycopeptide antibiotic teicoplanin as chiral selector. The liquid chromatograph was interfaced via electrospray ionization to a high resolution/high accuracy mass spectrometer, and urine samples were prepared for analysis following a protocol including enzymatic hydrolysis and subsequent liquid-liquid extraction. For proof-of-concept, authentic urine samples containing the target compounds were analyzed and their enantiomeric composition was assessed. The approach proved suitable for the chiral separation of a total of eight selected enantiomeric doping agents, allowing to determine their ratio at urinary concentrations relevant for sports drug testing purposes, i.e. between 0.01 and 2 ng/mL. Enantioselective assays provide the tool to overcome the limitations of non-chiral approaches in routine doping analysis and can offer support in studies where questions of pharmacokinetics and stereoselectivity are to be addressed for result management and decision-making processes.

Exploring the Interaction between Vancomycin/Teicoplanin and Receptor Binding Domain (RBD) of SARS-CoV-2

The recent pandemic caused by SARS-CoV-2 has spread to over 100 countries, infected more than 47 million people and resulted in more than 1.2 million deaths worldwide until October. It is well known that, the SARS-CoV-2 starts an infection by binding its Receptor Binding Domain (RBD) of spike protein to human Angiotensin converting enzyme 2 (ACE2) receptor, and strenuous efforts had been made to prevent the infection. However, no successful drugs or vaccines have appeared. Herein, molecular docking and molecular simulations were carried out to study the interaction between RBD and two glycopeptide antibiotics (Vancomycin and Teicoplanin). Key residues in binding pocket were highlighted and the binding free energies were calculated. Our results suggested that Vancomycin and Teicoplanin, as natural and accepted antibiotics, could block the interaction between RBD of spike protein and human ACE2 receptor, which might be developed to potential drugs against the SARS-CoV-2.

The reorganization of conformations, stability and aggregation of serum albumin isomers through the interaction of glycopeptide antibiotic teicoplanin: A thermodynamic and spectroscopy study

The drugs-protein binding study is of growing importance for drug-repurposing against amyloidosis. In this work, we study the binding of teicoplanin (TPN), a glycopeptide antibiotic, with bovine serum albumin (BSA) in its neutral (N), physiological (P) and basic (B) forms, which exist at pH 6, pH 7.4 and pH 9, respectively. The binding and thermodynamic parameters of TPN binding were determined by isothermal titration calorimetry (ITC) and fluorescence quench titration methods. Two binding sites were observed for N and P forms, whereas B form showed only one binding site. ITC and molecular docking results indicated that TPN-BSA complex formation is stabilized by hydrogen bonds, salt bridges and hydrophobic interaction. The red-edge excitation shift (REES) study indicated an ordered compact and spatial arrangement of the TPN bound protein molecule. TPN was found to affect the secondary and tertiary structures of B form only. The TPN binding was observed to marginally stabilize BSA isomers. TPN was also found to inhibit BSA aggregation as monitored by Rayleigh light scattering and thioflavin T binding assay. The current in vitro study will open a new path to explore the possible use of TPN as potential drugs to treat amyloidosis.

N-Terminal guanidine derivatives of teicoplanin antibiotics strongly active against glycopeptide resistant Enterococcus faecium.

Antibiotic resistance is one of the major challenges in healthcare of our time. To meet this challenge, we designed and prepared guanidine and lipophilic guanidine derivatives of the glycopeptide antibiotic teicoplanin to armed them with activity against the most threatening nosocomial bacteria, multiresistant enterococci. From teicoplanin and its pseudoaglycone, a series of N-terminal guanidine derivatives have been prepared with free and amide C-terminal parts. Six aliphatic and aromatic lipophilic carbodiimides were prepared and used for the synthesis of lipophilic guanidine teicoplanin conjugates. All new N-terminal guanidine antibiotics showed high activity against a standard panel of Gram-positive bacteria. Four selected derivatives displayed excellent antibacterial activity against a series of nosocomial VanA Enterococcus faecium strains.

De Novo Designed Hexadecapeptides Synergize Glycopeptide Antibiotics Vancomycin and Teicoplanin against Pathogenic Klebsiella pneumoniae via Disruption of Cell Permeability and Potential.

Given the worldwide prevalence of pathogenic drug-resistant bacteria and the slow pace of new antibacterial development, discovering new uses for approved drugs that are outside the scope of the original indication is increasingly becoming an attractive proposition. In this work, seven linear cationic hexadecapeptides were designed, synthesized, and characterized. These amphiphilic peptides are able to transform from the random coil structure in water to α-helix in SDS solution and have only modest bioactivity to limited bacterial strains when used alone. Surprisingly, one of them, namely, zp16, was found to demonstrate significant synergy with vancomycin and teicoplanin against highly pathogenic Klebsiella pneumoniae (KP) with FIC index as low as 0.03. Checkerboard assay indicated that, in the presence of 8 μM zp16, the minimum inhibitory concentration (MIC) of vancomycin greatly was reduced from >128 to 1 μM to clinically isolated carbapenem-resistant KP94. Additionally, the vancomycin-zp16 combination exhibited neglectable toxicity in vitro and in vivo. Further efficacy studies confirmed that the survival rate of a combination therapy at 100 mg/kg of zp16 and vancomycin was 30% higher than that of the single-drug treatment. More importantly, drug resistance has not developed to the combination even at the 20th serial passage of KP1088. Mechanistic studies revealed that zp16 could strengthen the vancomycin's influence on cell permeability and potential, leading to markedly reduced biofilm formation and rapid bactericidal effect. This new combination strategy expands the antibacterial spectrum of glycopeptide antibiotics and opens a new research direction for their application to treat pathogenic KP infection.

Genetic insights into the mechanism of teicoplanin self-resistance in Actinoplanes teichomyceticus

Actinoplanes teichomyceticus NRRL B-16726 is the only known producer of the clinically important glycopeptide antibiotic teicoplanin. The producing strain is highly self-resistant to teicoplanin. Although the biosynthesis of teicoplanin has been investigated, much of our understanding of self-resistance in the producing strain is based on the extrapolation of existing data about glycopeptide resistance (mediated by the expression of vanRS-vanHAX genes) in other actinomycetes and cocci. The organization of the operons carrying putative van orthologues in A. teichomyceticus differs from known precedents, further adding up to the uncertainty about teicoplanin self-resistance mechanisms. Here, we determined operon structure of the teicoplanin resistance genes in A. teichomyceticus. Although Tei15* is necessary to activate teicoplanin biosynthetic genes, the expression of van orthologues was shown to be independent of Tei15*. We further showed that tei7 promoter driving the expression of vanHAX orthologues is dependent on Tei2 (VanR). Finally, we demonstrate the utility of the tei2 promoter as a new tool to achieve strong constitutive expression in A. teichomyceticus.

Exploring modular reengineering strategies to redesign the teicoplanin non-ribosomal peptide synthetase.

Non-ribosomal peptide synthesis is an important biosynthesis pathway in secondary metabolism. In this study we have investigated modularisation and redesign strategies for the glycopeptide antibiotic teicoplanin. Using the relocation or exchange of domains within the NRPS modules, we have identified how to initiate peptide biosynthesis and explored the requirements for the functional reengineering of both the condensation/adenylation domain and epimerisation/condensation domain interfaces. We have also demonstrated strategies that ensure communication between isolated NRPS modules, leading to new peptide assembly pathways. This provides important insights into NRPS reengineering of glycopeptide antibiotic biosynthesis and has broad implications for the redesign of other NRPS systems.

Draft Genome Sequence of Teicoplanin-Producing Strain Actinoplanes teichomyceticus CPCC 203265.

We report here the draft genome sequence of Actinoplanes teichomyceticus CPCC 203265, a producer of glycopeptide antibiotic teicoplanin, which has significant inhibitory activity against multidrug-resistant Gram-positive pathogens. The draft genome size is 8 Mb, with a G+C content of 72.8%, and its sequence will facilitate the genome exploration of novel secondary metabolites.

Understanding the adaptive response of Streptomyces coelicolor to the glycopeptide antibiotic teicoplanin

Glycopeptide antibiotics are clinically important as a second-line therapy for the treatment for nosocomial infections caused by Gram-positive pathogens. A universal mode of action for glycopeptide antibiotics is to target the terminal residues, d-Alanyl-d-Alanine on the cell wall peptidoglycan intermediate lipid II, arresting the later stages of peptidoglycan biosynthesis. This weakens the cell wall, making it susceptible to rupture. A general resistance mechanism for glycopeptide antibiotics requires the core genes, vanRSHAX, that detect the presence of a glycopeptide (VanS) and upregulate genes (VanR) which orchestrate the remodelling of d-Ala-d-Ala on lipid II to d-Ala-d-Lactate (VanHAX). Glycopeptide affinity for lipid II is reduced by 1000-fold and biological activity impaired. Our previous study has shown that altering the termini of peptidoglycan precursors by VanHAX action was not sufficient for the resistance of the glycopeptide teicoplanin in S. coelicolor, which is instead mediated mainly by VanJ. Using RNA-seq, this study is designed to understand how the adaptive response in an S. coelicolor wild type (M600) and a vanJ mutant strain differ after exposure to teicoplanin. We have also compared these data with available data on the cell wall targeting antibiotics vancomycin, bacitracin and moenoymycin. By doing so, we aim to gain insight into the molecular basis of the improved activity of teicoplanin over vancomycin as well as identify novel cellular targets of teicoplanin which can help inform the design of future glycopeptides with desirable therapeutic properties.

Magnetic Nanoconjugated Teicoplanin: A Novel Tool for Bacterial Infection Site Targeting.

Nanoconjugated antibiotics can be regarded as next-generation drugs as they possess remarkable potential to overcome multidrug resistance in pathogenic bacteria. Iron oxide nanoparticles (IONPs) have been extensively used in the biomedical field because of their biocompatibility and magnetic properties. More recently, IONPs have been investigated as potential nanocarriers for antibiotics to be magnetically directed to/recovered from infection sites. Here, we conjugated the “last-resort” glycopeptide antibiotic teicoplanin to IONPs after surface functionalization with (3-aminopropyl) triethoxysilane (APTES). Classical microbiological methods and fluorescence and electron microscopy analysis were used to compare antimicrobial activity and surface interactions of naked IONPs, amino-functionalized NPs (NP-APTES), and nanoconjugated teicoplanin (NP-TEICO) with non-conjugated teicoplanin. As bacterial models, differently resistant strains of three Gram-positive bacteria (Staphylococcus aureus, Enterococcus faecalis, and Bacillus subtilis) and a Gram-negative representative (Escherichia coli) were used. The results indicated that teicoplanin conjugation conferred a valuable and prolonged antimicrobial activity to IONPs toward Gram-positive bacteria. No antimicrobial activity was detected using NP-TEICO toward the Gram-negative E. coli. Although IONPs and NP-APTES showed only insignificant antimicrobial activity in comparison to NP-TEICO, our data indicate that they might establish diverse interaction patterns at bacterial surfaces. Sensitivity of bacteria to NPs varied according to the surface provided by the bacteria and it was species specific. In addition, conjugation of teicoplanin improved the cytocompatibility of IONPs toward two human cell lines. Finally, NP-TEICO inhibited the formation of S. aureus biofilm, conserving the activity of non-conjugated teicoplanin versus planktonic cells and improving it toward adherent cells.

Hydrophobic Derivatives of Glycopeptide Antibiotics as Inhibitors of Protein Kinases.

As key regulators of cell signaling, protein kinases (PKs) are attractive targets for therapeutic intervention in a variety of diseases. Herein, we report for the first time the inhibitory activity of polycyclic peptides, particularly, derivatives of glycopeptide antibiotics teicoplanin and eremomycin, against a panel of 12 recombinant human protein kinases and two protein kinases (CK1 and CK2) isolated from rat liver. Several of the investigated compounds inhibited various PKs with IC50 values below 10 μM and caused >90% suppression of the enzyme activity at 10 μM concentration. Kinetic analysis of the protein kinase CK2α inhibition by the teicoplanin aglycon analogue (7) demonstrated the non-competitive mechanism of inhibition (with regard to ATP). Interestingly, the inhibitory activity of some investigated compounds correlated with the earlier described antiviral activity against HIV, HCV, and other corona- and flaviviruses.