{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,17]],"date-time":"2026-09-17T12:30:33Z","timestamp":1789648233721,"version":"4.0.0"},"reference-count":49,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2022,4,18]],"date-time":"2022-04-18T00:00:00Z","timestamp":1650240000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>The expression of the efflux pump systems is the most important mechanism of antibiotic resistance in bacteria, as it contributes to reduced concentration and the subsequent inactivity of administered antibiotics. NorA is one of the most studied antibacterial targets used as a model for efflux-mediated resistance. The present study evaluated shikimate pathway-derived phenolic acids against NorA (PDB ID: 1PW4) as a druggable target in antibacterial therapy using in silico modelling and in vitro methods. Of the 22 compounds evaluated, sinapic acid (\u22129.0 kcal\/mol) and p-coumaric acid (\u22126.3 kcal\/mol) had the best and most prominent affinity for NorA relative to ciprofloxacin, a reference standard (\u22124.9 kcal\/mol). A further probe into the structural stability and flexibility of the resulting NorA-phenolic acids complexes through molecular dynamic simulations over a 100 ns period revealed p-coumaric acid as the best inhibitor of NorA relative to the reference standard. In addition, both phenolic acids formed H-bonds with TYR 76, a crucial residue implicated in NorA efflux pump inhibition. Furthermore, the phenolic acids demonstrated favourable drug likeliness and conformed to Lipinski\u2019s rule of five for ADME properties. For the in vitro evaluation, the phenolic acids had MIC values in the range 31.2 to 62.5 \u03bcg\/mL against S. aureus, and E. coli, and there was an overall reduction in MIC following their combination with ciprofloxacin. Taken together, the findings from both the in silico and in vitro evaluations in this study have demonstrated high affinity of p-coumaric acid towards NorA and could be suggestive of its exploration as a novel NorA efflux pump inhibitor.<\/jats:p>","DOI":"10.3390\/molecules27082601","type":"journal-article","created":{"date-parts":[[2022,4,19]],"date-time":"2022-04-19T01:03:01Z","timestamp":1650330181000},"page":"2601","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["Computational Insights and In Vitro Validation of Antibacterial Potential of Shikimate Pathway-Derived Phenolic Acids as NorA Efflux Pump Inhibitors"],"prefix":"10.3390","volume":"27","author":[{"given":"Karishma","family":"Singh","sequence":"first","affiliation":[{"name":"Department of Biotechnology and Food Science, Faculty of Applied Sciences, Durban University of Technology, P.O. Box 1334, Durban 4000, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Roger M.","family":"Coopoosamy","sequence":"additional","affiliation":[{"name":"Department of Nature Conservation, Faculty of Natural Sciences, Mangosuthu University of Technology, P.O. Box 12363, Durban 4026, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4213-5416","authenticated-orcid":false,"given":"Njabulo J.","family":"Gumede","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Faculty of Natural Sciences, Mangosuthu University of Technology, P.O. Box 12363, Durban 4026, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7209-9220","authenticated-orcid":false,"given":"Saheed","family":"Sabiu","sequence":"additional","affiliation":[{"name":"Department of Biotechnology and Food Science, Faculty of Applied Sciences, Durban University of Technology, P.O. Box 1334, Durban 4000, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,4,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"28","DOI":"10.3923\/rjphyto.2017.28.34","article-title":"Antibacterial and molecular docking studies of bioactive component from leaves of Stachytarpheta cayennensis (Rich.) Vahl","volume":"11","author":"Subbaiah","year":"2016","journal-title":"Res. J. 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