title: Investigation of antibacterial mechanism and identification of bacterial protein targets mediated by antibacterial medicinal plant extracts.
abstract: In this paper, we investigated the antibacterial mechanism and potential therapeutic targets of three antibacterial medicinal plants. Upon treatment with the plant extracts, bacterial proteins were extracted and resolved using denaturing gel electrophoresis. Differentially-expressed bacterial proteins were excised from the gels and subjected to sequence analysis by MALDI TOF-TOF mass spectrometry. From our study, seven differentially expressed bacterial proteins (triacylglycerol lipase, N-acetylmuramoyl-L-alanine amidase, flagellin, outer membrane protein A, stringent starvation protein A, 30S ribosomal protein s1 and 60 kDa chaperonin) were identified. Additionally, scanning electron microscope study indicated morphological damages induced on bacterial cell surfaces. To the best of our knowledge, this represents the first time these bacterial proteins are being reported, following treatments with the antibacterial plant extracts. Further studies in this direction could lead to the detailed understanding of their inhibition mechanism and discovery of target-specific antibacterial agents.
authors.affiliation: Department of Chemical Science, Faculty of Science, Universiti Tunku Abdul Rahman, 31900 Kampar, Malaysia.
authors.forename: Ann-Li
authors.initials: AL
authors.lastname: Yong
authors.affiliation: Department of Chemical Science, Faculty of Science, Universiti Tunku Abdul Rahman, 31900 Kampar, Malaysia.
authors.forename: Keng-Fei
authors.initials: KF
authors.lastname: Ooh
authors.affiliation: Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Hean-Chooi
authors.initials: HC
authors.lastname: Ong
authors.affiliation: Centre for Biodiversity Research, Universiti Tunku Abdul Rahman, 31900 Kampar, Malaysia; Department of Chemical Science, Faculty of Science, Universiti Tunku Abdul Rahman, 31900 Kampar, Malaysia.
authors.forename: Tsun-Thai
authors.initials: TT
authors.lastname: Chai
authors.affiliation: Centre for Biodiversity Research, Universiti Tunku Abdul Rahman, 31900 Kampar, Malaysia; Department of Chemical Science, Faculty of Science, Universiti Tunku Abdul Rahman, 31900 Kampar, Malaysia. Electronic address: wongfc@utar.edu.my.
authors.forename: Fai-Chu
authors.initials: FC
authors.lastname: Wong
mesh_terms: D000900:Anti-Bacterial Agents / Q000032:analysis*; D001426:Bacterial Proteins / Q000737:chemistry*; D032408:Callicarpa / Q000737:chemistry; D002462:Cell Membrane / Q000737:chemistry; D018833:Chaperonins / Q000737:chemistry; D004926:Escherichia coli / Q000187:drug effects; D008401:Gas Chromatography-Mass Spectrometry; D008855:Microscopy, Electron, Scanning; D010936:Plant Extracts / Q000737:chemistry*; D010944:Plants / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry*; D031363:Scutellaria / Q000737:chemistry; D013211:Staphylococcus aureus / Q000187:drug effects
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D010936:Plant Extracts; D018833:Chaperonins
keywords: Callicarpa formosana; Escherichia coli; Melastoma candidum; Natural products; Protein expression; Scanning electron microscope; Scutellaria barbata; Staphylococcus aureus