scholarly journals Controlling Antibacterial Activity Exclusively with Visible Light: Introducing a Tetra‐ortho‐Chloro‐Azobenzene Amino Acid

2021 ◽  
Author(s):  
Xavier Just-Baringo ◽  
Alejandro Yeste-Vázquez ◽  
Javier Moreno-Morales ◽  
Clara Ballesté-Delpierre ◽  
Jordi Vila ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Amino Acid ◽  
Visible Light

Fluoroquinolone-3-carboxamide Amino Acid Conjugates: Synthesis, Antibacterial Properties And Molecular Modeling Studies

2020 ◽  
Vol 17 (1) ◽  
pp. 71-84
Author(s):  
Riham M. Bokhtia ◽  
Siva S. Panda ◽  
Adel S. Girgis ◽  
Hitesh H. Honkanadavar ◽  
Tarek S. Ibrahim ◽  
...  
Keyword(s):  
Experimental Data ◽  
Antibacterial Activity ◽  
Amino Acid ◽  
Bacterial Infections ◽  
Antibacterial Agents ◽  
Antibacterial Properties ◽  
Computational Studies ◽  
Protecting Group ◽  
Amino Acid Conjugates ◽  
Molecular Modeling Studies

Background: Bacterial infections are considered as one of the major global health threats, so it is very essential to design and develop new antibacterial agents to overcome the drawbacks of existing antibacterial agents. Method: The aim of this work is to synthesize a series of new fluoroquinolone-3-carboxamide amino acid conjugates by molecular hybridization. We utilized benzotriazole chemistry to synthesize the desired hybrid conjugates. Result: All the conjugates were synthesized in good yields, characterized, evaluated for their antibacterial activity. The compounds were screened for their antibacterial activity using methods adapted from the Clinical and Laboratory Standards Institute. Synthesized conjugates were tested for activity against medically relevant pathogens; Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27856) Staphylococcus aureus (ATCC 25923) and Enterococcus faecalis (ATCC 19433). Conclusion: The observed antibacterial experimental data indicates the selectivity of our synthesized conjugates against E.Coli. The protecting group on amino acids decreases the antibacterial activity. The synthesized conjugates are non-toxic to the normal cell lines. The experimental data were supported by computational studies.

scholarly journals SYNTHESIS AND ANTIMICROBIAL EVALUATION OF QUINAZOLINONE PEPTIDE DERIVATIVES

2017 ◽  
Vol 10 (16) ◽  
pp. 7 ◽  
Author(s):  
Bhupinder Kapoor ◽  
Arshid Nabi ◽  
Reena Gupta ◽  
Mukta Gupta
Keyword(s):  
Antibacterial Activity ◽  
Amino Acid ◽  
Antimicrobial Agents ◽  
Methyl Esters ◽  
Standard Drug ◽  
Amino Acid Peptide ◽  
Chemical Structures ◽  
1H Nuclear Magnetic Resonance ◽  
Peptide Derivatives ◽  
Derivatives Of

  Objective: The increased microbial resistance against commercially available drugs initiated the development of novel and safe antimicrobial agents in last few decades. In this view, a series of amino acid/dipeptide derivatives of quinazolin-3(4H)-one was synthesized and was evaluated for their antimicrobial potential.Method: Synthesis of amino acid/peptide derivatives were carried out by coupling 5-(2-(2-chlorophenyl)-4-oxoquinazolin-3(4H)-yl)-2-hydroxy benzoic acid with amino acid/dipeptide methyl esters in the presence of dicyclohexylcarbodiimide and N-methylmorpholine. The chemical structures of synthesized compounds were characterized by 1H nuclear magnetic resonance and infrared spectroscopy and were screened for antibacterial activity by disc diffusion method.Results: All the synthesized derivatives exhibited moderate to significant antibacterial activity against both Gram-positive and Gram-negative bacteria. The potency of compound 5d was comparable to standard drug ciprofloxacin in all the strains of bacteria used. The compound 5a was found to be more active against Streptococcus pyogenes and Staphylococcus aureus while compound 5c against Pseudomonas aeruginosa and Escherichia coli. Conclusion: Peptide derivatives of quinazolinone are promising antimicrobial agent and can be used for the synthesis of other novel compounds.

scholarly journals Visible Light-Induced Superior Photocatalytic Activity of Ag@Nd2WO6/ZnO Nanocomposite and its Biological Activity

2019 ◽  
Vol 9 (2S2) ◽  
pp. 232-236
Keyword(s):  
Antibacterial Activity ◽  
Visible Light ◽  
Uv Light ◽  
Uv Spectroscopy ◽  
Photocatalytic Process ◽  
Spectroscopy Technique ◽  
Phase Purity ◽  
X Ray ◽  
Uv Light Irradiation ◽  
Catalytic Material

In this work, degradation of Ciprofloxacin has been studied over the catalyst Ag@Nd2WO6/ZnO (ANWZ) synthesized via hydrothermal method. The catalysts are characterized with techniques such as X-ray diffractometer, Scanning electron microscope with EDX spectroscopy and DRS- UV spectroscopy respectively. For the results shows, the PXRD spectroscopy was confirmed a phase purity and crystalline structure of the as-synthesized catalyst. The SEM results are explained about the morphology structure of the material, the structure spherical with nanorod like clustered morphology structure was shown in SEM and the reacting elements in the catalytic material are confirmed by EDX spectroscopy. And the DRS-UV spectroscopy technique is telling about the band energy value for prepared materials and also select the suitable way (i.e: Visible or UV light irradiation) for the degradation. The photocatalytic process, Ciprofloxacin (CIP) drug are degraded under visible light within 140 minutes and the degradation efficiency are 95.54%. The reusability test explains the efficiency and stability of the ANWZ catalyst and its stable up to the fifth run. Further, the photodegradation process, the catalyst is tested antibacterial activity study against Bacillus cereus and Escherichia Coli bacterial organisms. From the result, Bacillus bacteria contain more efficient antibacterial activity than that of E.coli bacteria

scholarly journals Complete sequences of epidermin and nukacin encoding plasmids from oral-derived Staphylococcus epidermidis and their antibacterial activity

2021 ◽  
Author(s):  
Kenta Nakazono ◽  
Mi Nguyen-Tra Le ◽  
Miki Kawada-Matsuo ◽  
Noy Kimheang ◽  
Junzo Hisatsune ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Amino Acid ◽  
Staphylococcus Epidermidis ◽  
Activity Patterns ◽  
Bacterial Flora ◽  
Complete Sequence ◽  
Oral Bacteria ◽  
Amino Acid Sequences ◽  
Commensal Bacterium ◽  
Complete Sequences

AbstractStaphylococcus epidermidis is a commensal bacterium in humans. To persist in the bacterial flora of the host, some bacteria produce antibacterial factors such as the antimicrobial peptides known as bacteriocins. In this study, we tried to isolate bacteriocin-producing S. epidermidis strains. Among 150 S. epidermidis isolates from the oral cavities of 287 volunteers, we detected two bacteriocin-producing strains, KSE56 and KSE650. Complete genome sequences of the two strains confirmed that they carried the epidermin-harbouring plasmid pEpi56 and the nukacin IVK45-like- harbouring plasmid pNuk650. The amino acid sequence of epidermin from KSE56 was identical to the previously reported sequence, but the epidermin synthesis-related genes were partially different. The prepeptide amino acid sequences of nukacin KSE650 and nukacin IVK45 showed one mismatch, but both mature peptides were entirely similar. pNuk650 was larger and had an additional seven ORFs compared to pIVK45. We then investigated the antibacterial activity of the two strains against several skin and oral bacteria and found their different activity patterns. In conclusion, we report the complete sequences of 2 plasmids coding for bacteriocins from S. epidermidis, which were partially different from those previously reported. Furthermore, this is the first report to show the complete sequence of an epidermin-carrying plasmid, pEpi56.

scholarly journals Enhanced Antibacterial Activity of Silver Doped Titanium Dioxide-Chitosan Composites under Visible Light

Materials ◽  
2018 ◽  
Vol 11 (8) ◽  
pp. 1403 ◽  
Author(s):  
Jie Li ◽  
Bing Xie ◽  
Kai Xia ◽  
Yingchun Li ◽  
Jing Han ◽  
...  
Keyword(s):  
Particle Size ◽  
Antibacterial Activity ◽  
Titanium Dioxide ◽  
Visible Light ◽  
Silver Ions ◽  
Antibacterial Activities ◽  
Nano Tio2 ◽  
Inverse Emulsion ◽  
Potential Applications

Nano titanium dioxide (TiO2) with photocatalytic activity was firstly modified by diethanolamine, and it was then doped with broad spectrum antibacterial silver (Ag) by in situ method. Further, both Ag doped TiO2-chitosan (STC) and TiO2-chitosan (TC) composites were prepared by the inverse emulsion cross-linking reaction. The antibacterial activities of STC composites were studied and their antibacterial mechanisms under visible light were investigated. The results show that in situ doping and inverse emulsion method led to good dispersion of Ag and TiO2 nanoparticles on the cross-linked chitosan microsphere. The STC with regular particle size of 1–10 μm exhibited excellent antibacterial activity against E. coli, P. aeruginosa and S. aureus under visible light. It is believed that STC with particle size of 1–10 μm has large specific surface area to contact with bacterial cell wall. The increased antibacterial activity was attributed to the enhancement of both electron-hole separations at the surface of nano-TiO2 by the silver ions under the visible light, and the synergetic and sustained release of strong oxidizing hydroxyl radicals of nano-TiO2, together with silver ions against bacteria. Thus, STC composites have great potential applications as antibacterial agents in the water treatment field.

scholarly journals Sequence-dependent attack on peptides by photoactivated platinum anticancer complexes

2018 ◽  
Vol 9 (10) ◽  
pp. 2733-2739 ◽  
Author(s):  
Christopher A. Wootton ◽  
Carlos Sanchez-Cano ◽  
Andrea F. Lopez-Clavijo ◽  
Evyenia Shaili ◽  
Mark P. Barrow ◽  
...  
Keyword(s):  
Amino Acid ◽  
Visible Light ◽  
Amino Acid Composition ◽  
Acid Composition ◽  
Sequence Dependent ◽  
Anticancer Complexes

Octahedral anticancer platinum(iv) complexes such as trans,trans,trans-[Pt(N3)2(OH)2(pyridine)2] (1) can target peptides (and proteins) by sequence-dependent platination and radical mechanisms when activated by UVA or visible light; the specific products are highly dependent on their amino acid composition of the peptide.

scholarly journals Molecular Characterization of a Novel Lytic Enzyme LysC from Clostridium intestinale URNW and Its Antibacterial Activity Mediated by Positively Charged N-Terminal Extension

2020 ◽  
Vol 21 (14) ◽  
pp. 4894 ◽  
Author(s):  
Magdalena Plotka ◽  
Monika Szadkowska ◽  
Maria Håkansson ◽  
Rebeka Kovačič ◽  
Salam Al-Karadaghi ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Amino Acid ◽  
Hydrolytic Enzymes ◽  
Lytic Enzyme ◽  
Amino Acid Sequence Similarity ◽  
Scanning System ◽  
Strong Activity ◽  
Promising Alternative ◽  
Intrinsically Disordered ◽  
Positively Charged

Peptidoglycan hydrolytic enzymes are considered to be a promising alternative to conventional antibiotics in combating bacterial infections. To identify novel hydrolytic enzymes, we performed a database search with the sequences of two thermostable endolysins with high bactericidal activity, studied earlier in our laboratory. Both these enzymes originate from Thermus scotoductus bacteriophages MAT2119 and vB_Tsc2631. A lytic enzyme LysC from Clostridium intestinale URNW was found to have the highest amino acid sequence similarity to the bacteriophage proteins and was chosen for further analysis. The recombinant enzyme showed strong activity against its host bacteria C. intestinale, as well as against C. sporogenes, Bacillus cereus, Micrococcus luteus, and Staphylococcus aureus, on average causing a 5.12 ± 0.14 log reduction of viable S. aureus ATCC 25923 cells in a bactericidal assay. Crystallographic studies of the protein showed that the catalytic site of LysC contained a zinc atom coordinated by amino acid residues His50, His147, and Cys155, a feature characteristic for type 2 amidases. Surprisingly, neither of these residues, nor any other of the four conserved residues in the vicinity of the active site, His51, Thr52, Tyr76, and Thr153, were essential to maintain the antibacterial activity of LysC. Therefore, our attention was attracted to the intrinsically disordered and highly positively charged N-terminal region of the enzyme. Potential antibacterial activity of this part of the sequence, predicted by the Antimicrobial Sequence Scanning System, AMPA, was confirmed in our experimental studies; the truncated version of LysC (LysCΔ2–23) completely lacked antibacterial activity. Moreover, a synthetic peptide, which we termed Intestinalin, with a sequence identical to the first thirty amino acids of LysC, displayed substantial anti-staphylococcal activity with IC50 of 6 μg/mL (1.5 μM). This peptide was shown to have α-helical conformation in solution in the presence of detergents which is a common feature of amphipathic α-helical antimicrobial peptides.

Sign in / Sign up

Export Citation Format

Share Document