Journals / International Journal of Secondary Metabolite / 2026 / Volume: 13 Issue: 3

In vitro and bioinformatics evaluation of Origanum vulgare oil against Acinetobacter baumannii proteins

Gizem Köprülülü Küçük(İSTANBUL ŞİŞLİ MESLEK YÜKSEKOKULU)0000-0001-6667-4532
Tuğba Kaman(ÜSKÜDAR ÜNİVERSİTESİ)0000-0002-5885-0193
Ahmed Badri Abed(UŞAK ÜNİVERSİTESİ)0000-0002-7803-7917
Muhsin Konuk(ÜSKÜDAR ÜNİVERSİTESİ)0000-0002-6651-718X
Pages
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Publication Date
2026-09-02
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AI Summary & Key Takeaways

AI Insight
⚡ TL;DR(Too Long; Didn't Read)

These results support the potential of these essential oils as antimicrobial agents.

📌 3 Key Takeaways

🎯
Objective & Hypothesis:Acinetobacter baumannii is a highly pathogenic, multidrug-resistant bacterium, posing a significant clinical challenge.
📊
Key Findings & Data:Targeting key proteins such as OmpA and LigA offers potential for novel antimicrobial strategies.
💡
Conclusion & Impact:These results support the potential of these essential oils as antimicrobial agents.
🔬Design:Modeling & Simulation
📍Scope:Comprehensive Sample
⚙️Variables:Molecular Docking · Antibacterial Activity · Pharmacophore

Abstract

Acinetobacter baumannii is a highly pathogenic, multidrug-resistant bacterium, posing a significant clinical challenge. Targeting key proteins such as OmpA and LigA offers potential for novel antimicrobial strategies. In this study, we evaluated the antimicrobial activity of Origanum vulgare essential oil against A. baumannii strains and investigated the mechanism by which the main components (carvacrol, beta-caryophyllene, gamma-terpinene, thymol, and p-cymene) in the supplement have an antimicrobial effect on A. baumannii using computational techniques. Amino acid sequences for OmpA and LigA were obtained from NCBI and modeled in 3D using Swiss-Model, AlphaFold, and GalaxyWeb. Ligands were sourced from PubChem, and models were evaluated with PROCHECK and ERRAT, while active binding sites were identified through Consurf analysis. Protein-ligand docking was performed using HDOCK and AutoDock Vina, with interactions analyzed via the PLIP tool. The MIC values for Origanum vulgare were determined following CLSI guidelines, using emulsified oils and bacterial inocula in 96-well plates, incubated at 37°C for 24 hours, with MIC defined as the lowest concentration showing no growth, measured at 450 nm absorbance. For OmpA, HDOCK identified thymol (-95.53) and carvacrol (-93.58) as the top-scoring ligands, whereas AutoDock Vina highlighted γ-terpinene (-5.6) and p-cymene (-5.4). For LigA, carvacrol (-112.21) and thymol (-111.73) showed the strongest HDOCK binding, while AutoDock Vina favored p-cymene (-7.0) and carvacrol (-6.9). The lowest MIC against the A13 strain was observed with a 1/64 dilution of Origanum vulgare oil, while 1/16 and 1/32 dilutions inhibited other strains. These results support the potential of these essential oils as antimicrobial agents.

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Cite This Article

Küçük, G. K., Kaman, T., Abed, A. B., Korcan, S. E., Konuk, M. (2026). In vitro and bioinformatics evaluation of Origanum vulgare oil against Acinetobacter baumannii proteins. International Journal of Secondary Metabolite, Volume: 13 Issue: 3. https://doi.org/10.21448/ijsm.1791584

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References (59)

  1. Alomari, A., Gowland, R., Southwood, C., Barrow, J., Bentley, Z., Calvin-Nelson, J., Kaminski, A., LeFevre, M., Callaghan, A.J., Vincent, H.A., Gowers, D.M. (2021). Identification of Novel Inhibitors of Escherichia coli DNA Ligase (LigA). Molecules, 26(9), 2508. https://doi.org/10.3390/molecules26092508
  2. Andrade-Ochoa, S., Nevárez-Moorillón, G.V., Sánchez-Torres, L.E., Villanueva-García, M., Sánchez-Ramírez, B.E., Rodríguez-Valdez, L.M., & Rivera-Chavira, B.E. (2015). Quantitative structure–activity relationship of molecules constituent of different essential oils with antimycobacterial activity against Mycobacterium tuberculosis and Mycobacterium bovis. BMC Complementary and Alternative Medicine, 15, 1-11. https://doi.org/10.1186/s12906-015-0858-2
  3. Armon, A., Graur, D., & Ben-Tal, N. (2001). ConSurf: An algorithmic tool for the identification of functional regions in proteins by surface mapping of phylogenetic information. Journal of Molecular Biology, 307(1), 447-463. https://doi.org/10.1006/jmbi.2000.4474
  4. Avola, R., Granata, G., Geraci, C., Napoli, E., Graziano, A.C.E., Cardile, V. (2020). Oregano (Origanum vulgare L.) essential oil provides anti-inflammatory activity and facilitates wound healing in a human keratinocytes cell model. Food and Chemical Toxicology, 144, 111586. https://doi.org/10.1016/j.fct.2020.111586
  5. Ayoub Moubareck, C., & Hammoudi Halat, D. (2020). Insights into Acinetobacter baumannii: A Review of Microbiological, Virulence, and Resistance Traits in a Threatening Nosocomial Pathogen. Antibiotics, 9(3), 119. https://doi.org/10.3390/antibiotics9030119
  6. Azizi, Z.; Salimi, M.; Amanzadeh, A.; Majelssi, N.; Naghdi, N. (2020). Carvacrol and Thymol Attenuate Cytotoxicity Induced by Amyloid β25-35 via Activating Protein Kinase C and Inhibiting Oxidative Stress in PC12 Cells. Iran Biomedical Journal, 24, 243-250. https://doi.org/10.29252/ibj.24.4.243
  7. Baginska, S., Golognko, A., Swislocka, R., Lewandowski, W. (2023). Monoterpenes as medicinal agents: Exploring the pharmaceutical potential of p-cymene, p-cymenene, and γ-terpinene. Acta Poloniae Pharmaceutica- Drug Research, 80, 879-892. https://doi.org/10.32383/appdr/178242
  8. Ben Arfa, A., Combes, S., Preziosi-Belloy, L., Gontard, N., Chalier, P. (2006). Antimicrobial activity of carvacrol related to its chemical structure. Letters Apply Microbiology, 43, 149 154. https://doi.org/10.1111/j.1472-765X.2006.01938.x
  9. Bourhia, M., Alyousef, A.A., Doumane, G., Saghrouchni, H., Giesy, J.P., Ouahmane, L., Gueddari, F.E., Al-Sheikh, Y.A., Aboul-Soud, M.A.M. (2023). Volatile Constituents in Essential Oil from Leaves of Withania adpressa Coss. Ex Exhibit Potent Antioxidant and Antimicrobial Properties against Clinically-Relevant Pathogens. Molecules, 28, 2839. https://doi.org/10.3390/molecules28062839.
  10. Clinical and Laboratory Standards Institute. (2012). Methods for dilution antimicrobial susceptibility tests for bacteria that grow aerobically; approved standard (9th ed., CLSI document M07-A9). CLSI.
  11. Colovos, C., & Yeates, T.O. (1993). Verification of protein structures: Patterns of nonbonded atomic interactions. Protein Science, 2(9), 1511-1519. https://doi.org/10.1002/pro.5560020916
  12. da Silva Cirino, I.C., de Santana, C.F., Vasconcelos Rocha, I., de Souza, L.I.O., Silva, M.V., Bressan Queiroz de Figueiredo, R.C., Coutinho H.D.M., & Leal-Balbino, T.C. (2024). The Combinatory Effects of Essential Oil from Lippia macrophylla oil on multidrug-resistant Acinetobacter baumannii clinical isolates. Chemistry & Biodiversity, 21(10), e202400537. https://doi.org/10.1002/cbdv.202400537
  13. De Souza, G.H.D.A., dos Santos Radai, J.A., Mattos Vaz, M.S., Esther da Silva, K., Fraga, T.L., & Barbosa, L. (2021). In vitro and in vivo antibacterial activity assays of carvacrol: A candidate for the development of innovative treatments against KPC-producing Klebsiella pneumoniae. PLoS ONE, 16(2). https://doi.org/10.1371/journal.pone.0246003
  14. Erol, M., Çelik, I., & Kuyucuklu, G. (2021). Synthesis, molecular docking, molecular dynamics, DFT, and antimicrobial activity studies of 5-substituted-2-(p-methylphenyl) benzoxazole derivatives. Journal of Molecular Structure, 1234. https://doi.org/10.1016/j.molstruc.2021.130151
  15. Fikry, S., Khalil, N., & Salama, O., (2010). Chemical profiling, biostatic and biocidal dynamics of Origanum vulgare L. essential oil. AMB Express, 9, 41. https://doi.org/10.1186/s13568-019-0764-y
  16. Filimonov, D.A., Lagunin, A.A., Gloriozova, T.A., Rudik, A.V., Druzhilovskii, D.S., Pogodin, P.V., & Poroikov, V.V. (2014). Prediction of the biological activity spectra of organic compounds using the PASS online web resource. Chemistry of Heterocyclic Compounds, 50(3), 444 457. https://doi.org/10.1007/s10593-014-1496-1.
  17. Gill, A.O., Holley, R.A. (2006). Disruption of Escherichia coli, Listeria monocytogenes and Lactobacillus sakei cellular membranes by plant oil aromatics, International Journal of Food Microbiology, 108(1), 1-9. https://doi.org/10.1016/j.ijfoodmicro.2005.10.009
  18. Heidarian, S., Kachoie, M.A., Mousavi-Fard, S., & Moattar, F. (2024). Evaluating the chemical composition and antibacterial and antioxidant effects of the essential oil of Melissa officinalis L. Pakistan Journal of Zoology. DOI: https://dx.doi.org/10.17582/journal.pjz/20240309051129.
  19. Iyer, R., Moussa, S.H., Durand-Reville, T.F., Tommasi, R. & Miller, A. (2017). Acinetobacter baumannii OmpA is a selective antibiotic permeant porin. ACS Infection Diseases, 4, 373-381. https://doi.org/10.1021/acsinfecdis.7b00168
  20. Jumper, J., Evans, R., Pritzel, A., Green, T., Figurnov, M., Ronneberger, O., & Hassabis, D. (2021). Highly accurate protein structure prediction with AlphaFold. Nature, 596(7873), 583-589. https://doi.org/10.1038/s41586-021-03819-2
  21. Ko, J., Park, H., Heo, L., & Seok, C. (2012). GalaxyWEB server for protein structure prediction and refinement. Nucleic Acids Research, 40(W1), W294-W297. https://doi.org/10.1093/nar/gks493
  22. Lambert, R.J.W., Skandamis, P.N., Coote, P.J., Nychas, G.J.E. (2001). A study of the minimum inhibitory concentration and mode of action of oregano essential oil, thymol, and carvacrol, Journal of Applied Microbiology, 91, 453-462, https://doi.org/10.1046/j.1365-2672.2001.01428.x
  23. Li, Y., He, L., Xue, Z., Liang, Y., Jiang, J., Wei, Y., Li, H., He, H., Li, R. (2025). Antimicrobial activity of Origanum vulgare L. essential oil and its effects on fungal gene expression. PLoS One, 20(8).
  24. Lombrea, A., Antal, D., Ardelean, F., Avram, S., Pavel, I Z., Vlaia, L., & Danciu, C. (2020). A recent insight regarding the phytochemistry and bioactivity of Origanum vulgare L. essential oil. International Journal of Molecular Sciences, 21(24), 9653. https://doi.org/10.3390/ijms21249653.
  25. Ma, X., Li, H., Ji, J., Zeng, L., Tang, M., Lei, C., & Li, H. (2024). Overexpression of outer membrane protein A (OmpA) increases aminoglycoside sensitivity in mycobacteria. BMC Microbiology, 24(1), 472. https://doi.org/10.1186/s12866-024-03632-7
  26. Man, A., Santacroce, L., Jacob, R., Mare, A., & Man, L. (2019). Antimicrobial activity of six essential oils against a group of human pathogens: A comparative study. Pathogens, 8(3), 108. https://doi.org/10.3390/pathogens8030108
  27. Mechmechani, S., Gharsallaoui, A., Fadel, A., El Omari, K., Khelissa, S., Hamze, M., & Chihib, N.E. (2022). Microencapsulation of carvacrol as an efficient tool to fight Pseudomonas aeruginosa and Enterococcus faecalis biofilms. PLoS ONE, 17(7), e0270200. https://doi.org/10.1371/journal.pone.0270200
  28. Meier, T.I., Yan, D., Peery, R.B., McAllister, K.A., Zook, C., Peng, S.B., Zhao, G. (2008). Identification and characterization of an inhibitor specific to bacterial NAD+-dependent DNA ligases. FEBS Journal, 275(21):5258-71. https://doi.org/10.1111/j.1742-4658.2008.06652.x
  29. Meng, X.Y., Zhang, H.X., Mezei, M., & Cui, M. (2011). Molecular docking: a powerful approach for structure based drug discovery. Current Computer Aided Drug Design, 7, 146 157. https://doi.org/10.2174/157340911795677602
  30. Mills, S.D., Eakin, A.E., Buurman, E.T., Newman, J.V., Gao, N., Huynh, H., Johnson, K.D., Lahiri, S., Shapiro, A.B., Walkup, G.K., Yang, W., Stokes, S.S. (2011). Novel bacterial NAD+-dependent DNA ligase inhibitors with broad-spectrum activity and antibacterial efficacy in vivo. Antimicrob Agents Chemother, 55(3), 1088-96. https://doi.org/10.1128/AAC.01181-10
  31. Mortensen, B.L. & Skaar, E.P. (2012). Host–microbe interactions that shape the pathogenesis of A cinetobacter baumannii infection. Cell. Microbiology. 14, 1336 1344. https://doi.org/10.1111/j.1462 5822.2012.01817.x
  32. Nadeem, A., Ahmed, B., Shahzad, H., Craker, L.E., & Muntean, T. (2021). Verbascum thapsus (Mullein) versatile polarity extracts: GC-MS analysis, phytochemical profiling, antibacterial potential and antioxidant activity. Pharmacognosy Magazine, 13(51), 1488 1497. https://doi.org/10.5530/pj.2021.13.189
  33. National Center for Biotechnology Information. (2024, November 5). NCBI resources. https://www.ncbi.nlm.nih.gov
  34. National Library of Medicine. (2024, November 5). PubChem compound database. https://pubchem.ncbi.nlm.nih.gov
  35. Nie, D., Hu, Y., Chen, Z., Li, M., Hou, Z., Luo, X., Mao, X., Xue X. (2020). Outer membrane protein A (OmpA) as a potential therapeutic target for Acinetobacter baumannii infection. Journal of Biomedical Science, 27(1), 26. https://doi.org/10.1186/s12929-020-0617-7
  36. Pakzad, I., Yarkarami, F., Kalani, B. S., Shafieian, M., & Hematian, A. (2024). Inhibitory effects of carvacrol on biofilm formation in colistin heteroresistant Acinetobacter baumannii clinical isolates. Current Drug Discovery Technologies, 21(1), 119 124. https://doi.org/10.2174/0115701638253395230919112548 Pals, M.J., Lindberg, A., & Velema, W.A. (2024). Chemical strategies for antisense antibiotics. Chemical Society Reviews, 53(11), 11303-11320. https://doi.org/10.1039/d4cs00238e
  37. Pettersen, E.F., Goddard, T.D., Huang, C.C., Couch, G.S., Greenblatt, D.M., Meng, E.C., & Ferrin, T.E. (2004). UCSF Chimera: A visualization system for exploratory research and analysis. Journal of Computational Chemistry, 25(13), 1605–1612. https://doi.org/10.1002/jcc.20084
  38. Pogue, J.M., Zhou, Y., Kanakamedala, H., & Cai B. (2019). Burden of illness in carbapenem-resistant Acinetobacter baumannii infections in US hospitals between 2014 and 2019. BMC Infection Diseases, 22. https://doi.org/10.1186/s12879-021-07024-4
  39. Pinna, S., Kunz, C., Halpern, A., Harrison, S.A., Jordan, S.F., Ward, J., Werner, F., Lane, N. A (2022). Prebiotic basis for ATP as the universal energy currency. PLoS Biology, 20, e3001437. https://doi.org/10.1371/journal.pbio.3001437
  40. Prerna, P., Chadha, J., Khullar, L., Mudgil, U., & Harjai, K. (2024). A comprehensive review on the pharmacological prospects of terpinen-4-ol: From nature to medicine and beyond. Fitoterapia, 176, 106051. https://doi.org/10.1016/j.fitote.2024.106051.
  41. Protein–Ligand Interaction Profiler. (2024, December 15). PLIP web server. https://plip-tool.biotec.tu-dresden.de/plip-web/plip/index
  42. Radi, M.S., SalcedoSora, J.E., Kim, S.H., Sudarsan, S., Sastry, A.V., Kell, D.B., Herrgård, M.J., & Feist, A. M. (2022). Membrane transporter identification and modulation via adaptive laboratory evolution. Metabolic Engineering, 72, 376-390. https://doi.org/10.1016/j.ymben.2022.05.004
  43. Rattanachaikunsopon, P., Phumkhachorn, P. (2010). Assessment of factors influencing antimicrobial activity of carvacrol and cymene against Vibrio cholerae in food. Journal of Bioscience and Bioengineering, 110, 614-619. https://doi.org/10.1016/j.jbiosc.2010.06.010
  44. Scribano, D., Cheri, E., Pompilio, A. et al. Acinetobacter baumannii OmpA-like porins: functional characterization of bacterial physiology, antibiotic-resistance, and virulence. Communications Biology 7, 948. https://doi.org/10.1038/s42003-024-06645-0.
  45. Simirgiotis, M.J., Burton, D., Parra, F., López, J., Muñoz, P., Escobar, H., Parra, C. (2020). Antioxidant and Antibacterial Capacities of Origanum vulgare L. Essential Oil from the Arid Andean Region of Chile and its Chemical Characterization by GC MS. Metabolites. 10(10), 414. https://doi.org/10.3390/metabo10100414
  46. Skerniškytė, J. et al. (2019). The mutation of conservative Asp268 residue in the peptidoglycan-associated domain of the OmpA protein affects multiple Acinetobacter baumannii virulence characteristics. Molecules 24, 1972. https://doi.org/10.3390/molecules24101972
  47. Smani, Y., McConnell, M.J., Pachón, J. (2012). Role of fibronectin in the adhesion of Acinetobacter baumannii to host cells. PLoS ONE, 7. https://doi.org/10.1371/journal.pone.0033073
  48. Smani, Y., Fàbrega, A., Roca, I., Sánchez-Encinales, V., Vila, J., & Pachón, J. (2014). Role of OmpA in the multidrug resistance phenotype of Acinetobacter baumannii. Antimicrobial Agents Chemother, 58,1806-1808. https://doi.org/10.1128/AAC.02101-13
  49. Structural Analysis and Verification Server. (2024, December 12). https://saves.mbi.ucla.edu/
  50. Sugawara, E., & Nikaido, H. (2012). OmpA is the principal nonspecific slow porin of Acinetobacter baumannii. Journal of Bacteriology, 194(15), 4089-4096. https://doi.org/10.1128/JB.00435-12
  51. SwissADME. (2024, October 20). SwissADME: A free web tool to evaluate pharmacokinetics, drug-likeness, and medicinal chemistry friendliness of small molecules. https://www.swissadme.ch
  52. Tapia-Rodriguez, M.R., Cantu-Soto, E.U., Vazquez-Armenta, F.J., Bernal-Mercado, A.T., & Ayala-Zavala, J.F. (2023). Inhibition of Acinetobacter baumannii biofilm formation by terpenes from Oregano (Lippia graveolens) essential oil. Antibiotics, 12, 1539. https://doi.org/10.3390/antibiotics12101539
  53. Tiku, V. et al. (2021). Outer membrane vesicles containing OmpA induce mitochondrial fragmentation to promote pathogenesis of Acinetobacter baumannii. Scientific Reports. 11, 618. https://doi.org/10.1038/s41598-020-79966-9
  54. Trott, O., & Olson, A.J. (2010). AutoDock Vina: Improving the speed and accuracy of docking with a new scoring function, efficient optimization, and multithreading. Journal of Computational Chemistry, 31(2), 455-461. https://doi.org/10.1002/jcc.21334
  55. Ultee, A., Bennik, M.H.J., Moezelaar, R. (2002). The Phenolic Hydroxyl Group of Carvacrol Is Essential for Action against the Food-Borne Pathogen Bacillus cereus. Apply Environmental Microbiology, 68. https://doi.org/10.1128/AEM.68.4.1561-1568.2002
  56. Vaishnav, J., & Ampapathi, R.S. (2024). 1H, 15N, and 13C resonance backbone and side-chain assignments and secondary structure determination of the BRCT domain of Mtb LigA. Biomolecular NMR Assignments, 18, 1-5. https://doi.org/10.1007/s12104-024-10175-5
  57. Waterhouse, A., Bertoni, M., Bienert, S., Studer, G., Tauriello, G., Gumienny, R., Heer, F.T., de Beer, T.A.P., Rempfer, C., Bordoli, L., Lepore, R., & Schwede, T. (2018). SWISS-MODEL: Homology modeling of protein structures and complexes. Nucleic Acids Research, 46(W1), W296–W303. https://doi.org/10.1093/nar/gky427
  58. Way2Drug. (2024, October 20). PASS online: Prediction of activity spectra for biologically active substances. http://www.way2drug.com/passonline
  59. Yan, Y., Tao, H., He, J., & Huang, S.Y. (2020). The HDOCK server for integrated protein-protein docking. Nature Protocols, 15(5), 1829-1852. https://doi.org/10.1038/s41596-020-0312-x