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Wu X, Wang H, Xiong J, Yang GX, Hu JF, Zhu Q, Chen Z. Staphylococcus aureus biofilm: Formulation, regulatory, and emerging natural products-derived therapeutics. Biofilm 2024; 7:100175. [PMID: 38298832 PMCID: PMC10827693 DOI: 10.1016/j.bioflm.2023.100175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2023] [Revised: 12/21/2023] [Accepted: 12/30/2023] [Indexed: 02/02/2024] Open
Abstract
Staphylococcus aureus can readily form biofilm which enhances the drug-resistance, resulting in life-threatening infections involving different organs. Biofilm formation occurs due to a series of developmental events including bacterial adhesion, aggregation, biofilm maturation, and dispersion, which are controlled by multiple regulatory systems. Rapidly increasing research and development outcomes on natural products targeting S. aureus biofilm formation and/or regulation led to an emergent application of active phytochemicals and combinations. This review aimed at providing an in-depth understanding of biofilm formation and regulation mechanisms for S. aureus, outlining the most important antibiofilm strategies and potential targets of natural products, and summarizing the latest progress in combating S. aureus biofilm with plant-derived natural products. These findings provided further evidence for novel antibiofilm drugs research and clinical therapies.
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Affiliation(s)
- Xiying Wu
- Shanghai Skin Disease Hospital, Tongji University School of Medicine, Shanghai, 200443, China
- Institute of Natural Medicine and Health Products, School of Pharmaceutical Sciences, Zhejiang Provincial Key Laboratory of Plant Evolutionary Ecology and Conservation, Taizhou University, Zhejiang, 318000, China
- Department of Natural Medicine, School of Pharmacy, Fudan University, Shanghai, 201203, China
| | - Huan Wang
- School of Pharmacy, Naval Medical University, Shanghai, 200433, China
| | - Juan Xiong
- Department of Natural Medicine, School of Pharmacy, Fudan University, Shanghai, 201203, China
| | - Guo-Xun Yang
- Department of Natural Medicine, School of Pharmacy, Fudan University, Shanghai, 201203, China
| | - Jin-Feng Hu
- Institute of Natural Medicine and Health Products, School of Pharmaceutical Sciences, Zhejiang Provincial Key Laboratory of Plant Evolutionary Ecology and Conservation, Taizhou University, Zhejiang, 318000, China
| | - Quangang Zhu
- Shanghai Skin Disease Hospital, Tongji University School of Medicine, Shanghai, 200443, China
| | - Zhongjian Chen
- Shanghai Skin Disease Hospital, Tongji University School of Medicine, Shanghai, 200443, China
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Suwandecha T, Yingyongnarongkul BE, Towtawin K, Voravuthikunchai SP, Sriwiriyajan S. A Novel Antibiotic, Rhodomyrtone: Pharmacokinetic Studies in a Murine Model and Optimization and Validation of High-Performance Liquid Chromatographic Method for Plasma Analysis. Antibiotics (Basel) 2024; 13:156. [PMID: 38391542 PMCID: PMC10885983 DOI: 10.3390/antibiotics13020156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 01/09/2024] [Accepted: 01/16/2024] [Indexed: 02/24/2024] Open
Abstract
Rhodomyrtone has indisputable and undeniable potential as a new antibiotic for antibiotic-resistant Gram-positive bacteria. Therefore, the main objective of this study was to determine the pharmacokinetics profiles of orally administered rhodomyrtone in rats. A reverse-phase HPLC-UV method was developed, optimized and validated for the analysis of rhodomyrtone concentrations in rat plasma. The retention time of papaverine and rhodomyrtone was 3.928 and 5.937 min, with no interference with the excipients used. The lower limit of quantification (LLOQ) of rhodomyrtone in the plasma sample was 0.04 μg/mL, the accuracy of rhodomyrtone at the LLOQ level ranged from 93.64 to 106.36%, precision was 6.59%, 80-120% for accuracy and <20% CV for precision. The calibration curve was linear at concentrations ranging from 0.04 to 128 µg/mL with a correlation coefficient (r) value of equal to or greater than 0.999. Sprague Dawley rats received a single dose of rhodomyrtone at 50 and 100 mg/kg. Blood samples were collected from tail veins. The peak plasma concentration was observed at 2 h, and the area under the curve of rhodomyrtone at 50 mg/kg and 100 mg/kg was 3.41 ± 1.04 and 7.82 ± 1.53 μg·h/mL, respectively. The results demonstrated linear pharmacokinetics characteristics at the studied dosage range. The plasma concentration of rhodomyrtone was above the minimal inhibition concentrations of several common pathogenic bacteria of medical importance. The proposed HPLC-UV method is fast, cost-effective, reliable and reproducible, and it is proposed for the routine analysis of rhodomyrtone.
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Affiliation(s)
- Tan Suwandecha
- School of Pharmacy and Drug and Cosmetic Excellence Center, Walailak University, Thaiburi, Thasala District, Nakhon Si Thammarat 80160, Thailand
| | - Boon-Ek Yingyongnarongkul
- Department of Chemistry and Center of Excellence for Innovation in Chemistry (PERCH-CIC), Faculty of Science, Ramkhamhaeng University, Bangkok 10240, Thailand
| | - Kanokkan Towtawin
- Division of Health and Applied Science, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand
| | - Supayang Piyawan Voravuthikunchai
- Center of Antimicrobial Biomaterial Innovation-Southeast Asia and Natural Product Research Center of Excellence, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand
| | - Somchai Sriwiriyajan
- Division of Health and Applied Science, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand
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Ude Z, Flothkötter N, Sheehan G, Brennan M, Kavanagh K, Marmion CJ. Multi-targeted metallo-ciprofloxacin derivatives rationally designed and developed to overcome antimicrobial resistance. Int J Antimicrob Agents 2021; 58:106449. [PMID: 34644603 DOI: 10.1016/j.ijantimicag.2021.106449] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 09/28/2021] [Accepted: 10/02/2021] [Indexed: 10/20/2022]
Abstract
Antimicrobial resistance is a major global threat to human health due to the rise, spread and persistence of multi-drug-resistant bacteria or 'superbugs'. There is an urgent need to develop novel chemotherapeutics to overcome this overarching challenge. The authors derivatized a clinically used fluoroquinolone antibiotic ciprofloxacin (Cip), and complexed it to a copper phenanthrene framework. This resulted in the development of two novel metallo-antibiotics of general formula [Cu(N,N)(CipHA)]NO3 where N,N represents a phenanthrene ligand and CipHA represents a hydroxamic acid of Cip derivative. Comprehensive studies, including a detailed proteomic study in which Staphylococcus aureus cells were exposed to the complexes, were undertaken to gain an insight into their mode of action. These new complexes possess potent antibacterial activity against S. aureus and methicillin-resistant S. aureus. In addition, they were found to be well tolerated in vivo in Galleria mellonella larvae, which has both functional and structural similarities to the innate immune system of mammals. These findings suggest that proteins involved in virulence, pathogenesis, and the synthesis of nucleotides and DNA repair mechanisms are most affected. In addition, both complexes affected similar cell pathways when compared with clinically used Cip, including cationic antimicrobial peptide resistance. The Cu-DPPZ-CipHA (DPPZ = dipyrido[3,2-a:2',3'-c]phenazine) analogue also induces cell leakage, which leads to an altered proteome indicative of reduced virulence and increased stress.
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Affiliation(s)
- Ziga Ude
- Centre for Synthesis and Chemical Biology, Department of Chemistry, RCSI, University of Medicine and Health Sciences, Dublin, Ireland
| | - Nils Flothkötter
- Centre for Synthesis and Chemical Biology, Department of Chemistry, RCSI, University of Medicine and Health Sciences, Dublin, Ireland
| | - Gerard Sheehan
- SSPC Pharma Research Centre, Department of Biology, Maynooth University, Maynooth, Co. Kildare, Ireland
| | - Marian Brennan
- School of Pharmacy and Biomolecular Sciences, RCSI, University of Medicine and Health Sciences, Dublin, Ireland
| | - Kevin Kavanagh
- SSPC Pharma Research Centre, Department of Biology, Maynooth University, Maynooth, Co. Kildare, Ireland.
| | - Celine J Marmion
- Centre for Synthesis and Chemical Biology, Department of Chemistry, RCSI, University of Medicine and Health Sciences, Dublin, Ireland.
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4
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Rhodomyrtus tomentosa (Aiton.): A review of phytochemistry, pharmacology and industrial applications research progress. Food Chem 2020; 309:125715. [DOI: 10.1016/j.foodchem.2019.125715] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 10/05/2019] [Accepted: 10/14/2019] [Indexed: 12/16/2022]
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Unusual features and molecular pathways of Staphylococcus aureus L-form bacteria. Microb Pathog 2020; 140:103970. [PMID: 31918001 DOI: 10.1016/j.micpath.2020.103970] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 01/04/2020] [Accepted: 01/05/2020] [Indexed: 12/31/2022]
Abstract
Staphylococcus aureus can be converted to cell wall-deficient L-form bacteria in specific environment which is associated with recurrent and persistent infections. The biophysical properties and molecular basis involved in S. aureus L-form formation are poorly understood. Here, S. aureus unstable L-form model was established not only in Newman strain, but also in ATCC 25923 and five different antibiotic-resistant clinical strains, and the morphology and mechanical properties of Newman strain L-forms were characterized by using atomic force microscopy. Meanwhile, zeta potential, growth and proliferation properties, and hemolysis of L-forms were determined. Gene expression changes involved in transition from S. aureus wild type into L-forms were identified. Our studies showed that L-form S. aureus presented pleomorphism, rough surface, and higher elasticity modulus. L-forms were characterized by less surface charge and had higher hemolysis than the walled form. The S. aureus L-form "fried egg" colony was derived from a single bacterium rather than from aggregation of different bacterial cells. Transcriptomics analysis revealed that several pathways involved in energy metabolism, stress response, protein synthesis, RNA metabolism, and virulence were involved in L-form formation in S. aureus. Our results shed new light on the biological properties and mechanisms underlying L-form formation in S. aureus. These findings will not only be useful for understanding the unique properties and mechanisms of L-form bacteria, but also provide therapeutic targets for developing more effective treatments for S. aureus L-forms.
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Mitsuwan W, Jiménez-Munguía I, Visutthi M, Sianglum W, Rodríguez-Ortega MJ, Voravuthikunchai SP. Rhodomyrtone decreases Staphylococcus aureus SigB activity during exponentially growing phase and inhibits haemolytic activity within membrane vesicles. Microb Pathog 2019; 128:112-118. [PMID: 30583020 DOI: 10.1016/j.micpath.2018.12.019] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 12/07/2018] [Accepted: 12/11/2018] [Indexed: 02/05/2023]
Abstract
Sigma factor B (SigB) controls the expression of Staphylococcus aureus genes including virulence factors and plays a role in the bacterial secretion system through membrane vesicle production. Inhibition of SigB could attenuate SigB dependent virulence and secretion system. The objective of this study was to determine the effects of rhodomyrtone on SigB and virulence factors related to SigB. Minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) values of rhodomyrtone against 67 clinical methicillin-resistant S. aureus isolates were 0.25-8 μg/ml, which were similar to those of vancomycin. Using luciferase gene fused to SigB dependent promoters of asp23, five time reduction in SigB activity was observed when the bacteria were treated with rhodomyrtone for 3 h. Rhodomyrtone significantly reduced SigB activity in a concentration dependent manner in exponentially growing cells (P < 0.05). In addition, sigB mutant was more sensitive towards increasing concentrations of rhodomyrtone than the wild type and yabJ-spoVG mutant. Rhodomyrtone at 0.625 μg/ml reduced the growth of sigB mutant by approximately 99%, compared with the yabJ-spoVG mutant and the wild type. Membrane vesicles were significantly reduced in the bacterial cells when treated with 0.5 × MIC rhodomyrtone (P < 0.05). Decreased haemolytic activity was detected within rhodomyrtone-treated membrane vesicles. The results indicated that rhodomyrtone inhibited S. aureus SigB activity during exponentially growing phase and inhibited haemolytic activity within membrane vesicles.
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Affiliation(s)
- Watcharapong Mitsuwan
- Department of Microbiology and Excellent Research Laboratory on Natural Products and Natural Product Research Center of Excellence, Faculty of Science, Prince of Songkla University, Songkhla, Thailand
| | - Irene Jiménez-Munguía
- Departamento de Bioquímica y Biología Molecular, Universidad de Córdoba, Campus de Excelencia Internacional CeiA3, Córdoba, Spain; Department of Engineering of Technological Equipment, National University of Science and Technology "MISiS", Moscow, Russia
| | - Monton Visutthi
- Department of Microbiology and Excellent Research Laboratory on Natural Products and Natural Product Research Center of Excellence, Faculty of Science, Prince of Songkla University, Songkhla, Thailand
| | - Wipawadee Sianglum
- Department of Microbiology and Excellent Research Laboratory on Natural Products and Natural Product Research Center of Excellence, Faculty of Science, Prince of Songkla University, Songkhla, Thailand
| | | | - Manuel J Rodríguez-Ortega
- Departamento de Bioquímica y Biología Molecular, Universidad de Córdoba, Campus de Excelencia Internacional CeiA3, Córdoba, Spain
| | - Supayang P Voravuthikunchai
- Department of Microbiology and Excellent Research Laboratory on Natural Products and Natural Product Research Center of Excellence, Faculty of Science, Prince of Songkla University, Songkhla, Thailand.
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The Health Beneficial Properties of Rhodomyrtus tomentosa as Potential Functional Food. Biomolecules 2019; 9:biom9020076. [PMID: 30795643 PMCID: PMC6406238 DOI: 10.3390/biom9020076] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 02/15/2019] [Accepted: 02/18/2019] [Indexed: 12/16/2022] Open
Abstract
Rhodomyrtus tomentosa (Aiton) Hassk. is a flowering plant belonging to the family Myrtaceae, native to southern and southeastern Asia. It has been used in traditional Vietnamese, Chinese, and Malaysian medicine for a long time for the treatment of diarrhea, dysentery, gynecopathy, stomachache, and wound healing. Moreover, R. tomentosa is used to make various food products such as wine, tea, and jam. Notably, R. tomentosa has been known to contain structurally diverse and biologically active metabolites, thus serving as a potential resource for exploring novel functional agents. Up to now, numerous phenolic and terpenoid compounds from the leaves, root, or fruits of R. tomentosa have been identified, and their biological activities such as antioxidant, antibacterial, anti-inflammatory, and anticancer have been evidenced. In this contribution, an overview of R. tomentosa and its health beneficial properties was focused on and emphasized.
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Zhao LY, Liu HX, Wang L, Xu ZF, Tan HB, Qiu SX. Rhodomyrtosone B, a membrane-targeting anti-MRSA natural acylgphloroglucinol from Rhodomyrtus tomentosa. JOURNAL OF ETHNOPHARMACOLOGY 2019; 228:50-57. [PMID: 30195566 DOI: 10.1016/j.jep.2018.09.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2017] [Revised: 07/30/2018] [Accepted: 09/05/2018] [Indexed: 06/08/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE The leaves of Rhodomyrtus tomentosa are traditionally used in the treatment of infectious diseases such as wound infections in Chinese traditional medicine. The mechanisms of the activity of rhodomyrtosone B (RDSB), a natural acylphloroglucinol isolated from the leaves of Rhodomyrtus tomentosa, are still not understood. We provided a detailed investigation of the antibacterial action of RDSB against bacteria in vitro and in vivo. MATERIALS AND METHODS The antibacterial activity of RDSB was tested by the microdilution method against a panel of bacteria, and a time-killing assay was carried out according to CLSI guidelines. The cytotoxic potential of RDSB was evaluated against mammalian cells, and its haemolytic activity towards rabbit red blood cells (RBCs) was assessed. The mode of action of RDSB was investigated by targeting bacterial membranes, and its resistance was evaluated using a sequential passaging method. The antibacterial activities in vivo were assessed against MRSA in a mouse skin infection mode. RESULTS RDSB exhibited distinct antibacterial activities against selected Gram-positive pathogens responsible for serious infections, even including methicillin-resistant Staphylococcus aureus (MRSA) with a minimum inhibitory concentration (MIC) of 0.62-1.25 µg/mL and vancomycin-resistant Enterococcus faecium (VRE) with an MIC of 2.5 µg/mL. RDSB displayed much more rapid bactericidal activity against MRSA than that of vancomycin. The membrane-targeting experiments revealed that RDSB exhibited significant antibacterial activity with the perturbation of bacterial membrane potential and an increase in membrane permeability. In particular, RDSB had weak cytotoxicity to mammalian cells (IC50 >14 µg/mL) and has advantageous specificity against selected Gram-positive bacterial membranes rather than RBCs. Notably, RDSB displayed in vitro antibacterial activities against MRSA without drug-resistance and profoundly attenuated the skin ulcer formation in a murine model of MRSA infection under a single dose of 40 µg RDSB per mouse. CONCLUSION RDSB has profound antibacterial activity against drug-resistant bacteria (MRSA and VRE) and low cytotoxicity. It is bactericidal in nature, and an increase in membrane permeability resulting from membrane perturbation is one of its modes of action. RDSB represents a promising natural antibiotic to combat drug-resistant (MRSA and VRE) infections.
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Affiliation(s)
- Li-Yun Zhao
- Program for Natural Product Chemical Biology, Key Laboratory of Plant Resources Conservation and Sustainable Utilization, Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, People's Republic of China; University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Hong-Xin Liu
- Program for Natural Product Chemical Biology, Key Laboratory of Plant Resources Conservation and Sustainable Utilization, Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, People's Republic of China
| | - Lei Wang
- Institute of Hypertension, School of Medicine, Sun Yat-Sen University, Guangzhou 510085, People's Republic of China
| | - Zhi-Fang Xu
- Program for Natural Product Chemical Biology, Key Laboratory of Plant Resources Conservation and Sustainable Utilization, Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, People's Republic of China
| | - Hai-Bo Tan
- Program for Natural Product Chemical Biology, Key Laboratory of Plant Resources Conservation and Sustainable Utilization, Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, People's Republic of China.
| | - Sheng-Xiang Qiu
- Program for Natural Product Chemical Biology, Key Laboratory of Plant Resources Conservation and Sustainable Utilization, Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, People's Republic of China.
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Structures and Bioactive Properties of Myrtucommulones and Related Acylphloroglucinols from Myrtaceae. Molecules 2018; 23:molecules23123370. [PMID: 30572614 PMCID: PMC6321051 DOI: 10.3390/molecules23123370] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2018] [Revised: 12/14/2018] [Accepted: 12/17/2018] [Indexed: 12/13/2022] Open
Abstract
Myrtaceae are a group of plants that include a number of renowned species used in ethnomedicine in many areas worldwide. Their valuable therapeutic properties have stimulated a fruitful research activity addressed to the identification of the bioactive components of their extracts yielding a great diversity of terpenes; polyphenols; and other exclusive products. Among the latter, starting with the discovery of myrtucommulone A from myrtle (Myrtus communis), a series of structurally-related acylphloroglucinol compounds have been characterized from several species that represent the basic active principles to be considered in view of possible drug development. Aspects concerning chemical and biological properties of these products are reviewed in the present paper.
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Antibacterial activity of rhodomyrtone on Clostridium difficile vegetative cells and spores in vitro. Int J Antimicrob Agents 2018; 52:724-729. [PMID: 30145248 DOI: 10.1016/j.ijantimicag.2018.08.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Revised: 08/04/2018] [Accepted: 08/18/2018] [Indexed: 11/20/2022]
Abstract
The increasing incidence and severity of diarrhoea and colitis caused by Clostridium difficile, together with a high rate of relapse following treatment with currently recommended antimicrobials, calls for novel interventions for C. difficile infection (CDI). Rhodomyrtone, a bioactive compound derived from the leaves of the rose myrtle (Rhodomyrtus tomentosa) has demonstrated antibacterial activity against several Gram-positive bacteria. This study compared the in vitro antimicrobial activity of rhodomyrtone on C. difficile with that of vancomycin, a recommended agent for the treatment of CDI. Determination of the minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) of rhodomyrtone and vancomycin for ten C. difficile isolates showed that the MICs of rhodomyrtone for C. difficile vegetative cells (0.625-2.5 mg/L) were comparable with that of vancomycin (1.25 mg/L), but the MBCs of rhodomyrtone (1.25-5 mg/L) were significantly lower than those for vancomycin (5 mg/L to ˃40 mg/L; P < 0.001). Time-kill assays showed rapid bactericidal activity for rhodomyrtone, with ≥99% killing within 4 h. Rhodomyrtone was also four-fold more potent than vancomycin in inhibiting C. difficile spore outgrowth. Transmission electron microscopy of rhodomyrtone-treated C. difficile revealed cell lysis and evidence of defective cell division and spore formation. These studies indicate that rhodomyrtone should be further investigated as a potential treatment for CDI.
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Saising J, Nguyen MT, Härtner T, Ebner P, Al Mamun Bhuyan A, Berscheid A, Muehlenkamp M, Schäkermann S, Kumari N, Maier ME, Voravuthikunchai SP, Bandow J, Lang F, Brötz-Oesterhelt H, Götz F. Rhodomyrtone (Rom) is a membrane-active compound. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1860:1114-1124. [PMID: 29317198 DOI: 10.1016/j.bbamem.2018.01.011] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 12/15/2017] [Accepted: 01/04/2018] [Indexed: 12/24/2022]
Abstract
Particularly in Asia medicinal plants with antimicrobial activity are used for therapeutic purpose. One such plant-derived antibiotic is rhodomyrtone (Rom) isolated from Rhodomyrtus tomentosa leaves. Rom shows high antibacterial activity against a wide range of Gram-positive bacteria, however, its mode of action is still unclear. Reporter gene assays and proteomic profiling experiments in Bacillus subtilis indicate that Rom does not address classical antibiotic targets like translation, transcription or DNA replication, but acts at the cytoplasmic membrane. In Staphylococcus aureus, Rom decreases the membrane potential within seconds and at low doses, causes release of ATP and even the excretion of cytoplasmic proteins (ECP), but does not induce pore-formation as for example nisin. Lipid staining revealed that Rom induces local membrane damage. Rom's antimicrobial activity can be antagonized in the presence of a very narrow spectrum of saturated fatty acids (C15:0, C16:0, or C18:0) that most likely contribute to counteract the membrane damage. Gram-negative bacteria are resistant to Rom, presumably due to reduced penetration through the outer membrane and its neutralization by LPS. Rom is cytotoxic for many eukaryotic cells and studies with human erythrocytes showed that Rom induces eryptosis accompanied by erythrocyte shrinkage, cell membrane blebbing, and membrane scrambling with phosphatidylserine translocation to the erythrocyte surface. Rom's distinctive interaction with the cytoplasmic membrane reminds on the amphipathic, alpha-helical peptides, the phenol-soluble modulins (PSMs), and renders Rom an important tool for the investigation of membrane physiology.
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Affiliation(s)
- Jongkon Saising
- Microbial Genetics, Interfaculty Institute of Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Tübingen, Germany; School of Health Science, Mae Fah Luang University, Muang, Chiang Rai 57100, Thailand
| | - Minh-Thu Nguyen
- Microbial Genetics, Interfaculty Institute of Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Tübingen, Germany; School of Biological and Food Technology, Hanoi University of Science and Technology, Hanoi, Viet Nam
| | - Thomas Härtner
- Biotechnology, Interfaculty Institute of Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Tübingen, Germany
| | - Patrick Ebner
- Microbial Genetics, Interfaculty Institute of Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Tübingen, Germany
| | | | - Anne Berscheid
- Microbial Bioactive Compounds, Interfaculty Institute of Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Germany
| | - Melanie Muehlenkamp
- Microbial Bioactive Compounds, Interfaculty Institute of Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Germany
| | | | - Nimerta Kumari
- Microbial Genetics, Interfaculty Institute of Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Tübingen, Germany
| | - Martin E Maier
- Institut für Organische Chemie, Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
| | | | - Julia Bandow
- Applied Microbiology, Ruhr University Bochum, Bochum, Germany
| | - Florian Lang
- Departments of Cardiology, Vascular Medicine & Physiology, University of Tübingen, Germany
| | - Heike Brötz-Oesterhelt
- Microbial Bioactive Compounds, Interfaculty Institute of Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Germany
| | - Friedrich Götz
- Microbial Genetics, Interfaculty Institute of Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Tübingen, Germany.
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Sianglum W, Saeloh D, Tongtawe P, Wootipoom N, Indrawattana N, Voravuthikunchai SP. Early Effects of Rhodomyrtone on Membrane Integrity in Methicillin-Resistant Staphylococcus aureus. Microb Drug Resist 2017; 24:882-889. [PMID: 29215320 DOI: 10.1089/mdr.2016.0294] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Strong evidence of high potency of rhodomyrtone as a promising antibacterial agent against pathogenic gram-positive bacteria has been clearly demonstrated in our previous work. The aim of this study was to provide insight into early action of rhodomyrtone, an acylphloroglucinol, on membrane damage in multidrug-resistant methicillin-resistant Staphylococcus aureus (MRSA). Early effects of rhodomyrtone on the bacterial membrane integrity were detected in a time-course study. Flow cytometry revealed a reduction in green fluorescent emission and increase in uptake of propidium iodide in rhodomyrtone-treated bacterial cells in a concentration- and time-dependent manner. Disruption of cytoplasmic membrane was further monitored by measuring cellular adenosine triphosphate (ATP) and potassium ion (K+). Leakage of both ATP and K+ and significant decrease in intracellular ATP in MRSA were observed following treatment. Pronounced changes in the bacterial ultrastructure and morphology were confirmed by transmission electron microscopy and scanning electron microscopy. Bacterial cell disruption, holes in cell surface, and bulge formations were noted in rhodomyrtone-treated cells. In this study, we provided relevant data to clarify that rhodomyrtone is a bacterial cell membrane-damaging agent. A possible early effect of this novel compound involves bacterial membrane disruption.
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Affiliation(s)
- Wipawadee Sianglum
- 1 Department of Microbiology and Excellence Research Laboratory on Natural Products, Faculty of Science and Natural Product Research Center of Excellence, Prince of Songkla University , Hat Yai, Thailand
| | - Dennapa Saeloh
- 2 Faculty of Medical Technology, Prince of Songkla University , Hat Yai, Thailand
| | - Pongsri Tongtawe
- 3 Graduate Program in Biomedical Sciences, Faculty of Allied Health Sciences, Thammasat University , Pathumtanee, Thailand
| | - Natthakul Wootipoom
- 4 Immunology and Virology Unit, Department of Pathology, Faculty of Medicine, Prince of Songkla University , Hat Yai, Thailand
| | - Nitaya Indrawattana
- 5 Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University , Bangkok, Thailand
| | - Supayang Piyawan Voravuthikunchai
- 1 Department of Microbiology and Excellence Research Laboratory on Natural Products, Faculty of Science and Natural Product Research Center of Excellence, Prince of Songkla University , Hat Yai, Thailand
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Saeloh D, Wenzel M, Rungrotmongkol T, Hamoen LW, Tipmanee V, Voravuthikunchai SP. Effects of rhodomyrtone on Gram-positive bacterial tubulin homologue FtsZ. PeerJ 2017; 5:e2962. [PMID: 28168121 PMCID: PMC5292029 DOI: 10.7717/peerj.2962] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Accepted: 01/05/2017] [Indexed: 12/15/2022] Open
Abstract
Rhodomyrtone, a natural antimicrobial compound, displays potent activity against many Gram-positive pathogenic bacteria, comparable to last-defence antibiotics including vancomycin and daptomycin. Our previous studies pointed towards effects of rhodomyrtone on the bacterial membrane and cell wall. In addition, a recent molecular docking study suggested that the compound could competitively bind to the main bacterial cell division protein FtsZ. In this study, we applied a computational approach (in silico), in vitro, and in vivo experiments to investigate molecular interactions of rhodomyrtone with FtsZ. Using molecular simulation, FtsZ conformational changes were observed in both (S)- and (R)-rhodomyrtone binding states, compared with the three natural states of FtsZ (ligand-free, GDP-, and GTP-binding states). Calculations of free binding energy showed a higher affinity of FtsZ to (S)-rhodomyrtone (−35.92 ± 0.36 kcal mol−1) than the GDP substrate (−23.47 ± 0.25 kcal mol−1) while less affinity was observed in the case of (R)-rhodomyrtone (−18.11 ± 0.11 kcal mol−1). In vitro experiments further revealed that rhodomyrtone reduced FtsZ polymerization by 36% and inhibited GTPase activity by up to 45%. However, the compound had no effect on FtsZ localization in Bacillus subtilis at inhibitory concentrations and cells also did not elongate after treatment. Higher concentrations of rhodomyrtone did affect localization of FtsZ and also affected localization of its membrane anchor proteins FtsA and SepF, showing that the compound did not specifically inhibit FtsZ but rather impaired multiple divisome proteins. Furthermore, a number of cells adopted a bean-like shape suggesting that rhodomyrtone possibly possesses further targets involved in cell envelope synthesis and/or maintenance.
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Affiliation(s)
- Dennapa Saeloh
- Excellence Research Laboratory on Natural Products, Faculty of Science and Natural Product Research Center of Excellence, Prince of Songkla University, Hat Yai, Thailand; Department of Microbiology, Faculty of Science, Prince of Songkla University, Hat Yai, Thailand
| | - Michaela Wenzel
- Bacterial Cell Biology, Swammerdam Institute for Life Sciences, University of Amsterdam , Amsterdam , Netherlands
| | - Thanyada Rungrotmongkol
- Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok, Thailand; Center of Innovative Nanotechnology, Chulalongkorn University, Bongkok, Thailand
| | - Leendert Willem Hamoen
- Bacterial Cell Biology, Swammerdam Institute for Life Sciences, University of Amsterdam , Amsterdam , Netherlands
| | - Varomyalin Tipmanee
- Excellence Research Laboratory on Natural Products, Faculty of Science and Natural Product Research Center of Excellence, Prince of Songkla University, Hat Yai, Thailand; Department of Biomedical Science, Faculty of Medicine, Prince of Songkla University, Hat Yai, Thailand
| | - Supayang Piyawan Voravuthikunchai
- Excellence Research Laboratory on Natural Products, Faculty of Science and Natural Product Research Center of Excellence, Prince of Songkla University, Hat Yai, Thailand; Department of Microbiology, Faculty of Science, Prince of Songkla University, Hat Yai, Thailand
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14
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Dou JL, Jiang YW, Xie JQ, Zhang XG. New Is Old, and Old Is New: Recent Advances in Antibiotic-Based, Antibiotic-Free and Ethnomedical Treatments against Methicillin-Resistant Staphylococcus aureus Wound Infections. Int J Mol Sci 2016; 17:E617. [PMID: 27120596 PMCID: PMC4881443 DOI: 10.3390/ijms17050617] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Revised: 04/18/2016] [Accepted: 04/19/2016] [Indexed: 12/26/2022] Open
Abstract
Staphylococcus aureus is the most common pathogen of wound infections. Thus far, methicillin-resistant S. aureus (MRSA) has become the major causative agent in wound infections, especially for nosocomial infections. MRSA infections are seldom eradicated by routine antimicrobial therapies. More concerning, some strains have become resistant to the newest antibiotics of last resort. Furthermore, horizontal transfer of a polymyxin resistance gene, mcr-1, has been identified in Enterobacteriaceae, by which resistance to the last group of antibiotics will likely spread rapidly. The worst-case scenario, "a return to the pre-antibiotic era", is likely in sight. A perpetual goal for antibiotic research is the discovery of an antibiotic that lacks resistance potential, such as the recent discovery of teixobactin. However, when considering the issue from an ecological and evolutionary standpoint, it is evident that it is insufficient to solve the antibiotic dilemma through the use of antibiotics themselves. In this review, we summarized recent advances in antibiotic-based, antibiotic-free and ethnomedical treatments against MRSA wound infections to identify new clues to solve the antibiotic dilemma. One potential solution is to use ethnomedical drugs topically. Some ethnomedical drugs have been demonstrated to be effective antimicrobials against MRSA. A decline in antibiotic resistance can therefore be expected, as has been demonstrated when antibiotic-free treatments were used to limit the use of antibiotics. It is also anticipated that these drugs will have low resistance potential, although there is only minimal evidence to support this claim to date. More clinical trials and animal tests should be conducted on this topic.
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Affiliation(s)
- Jian-Lin Dou
- Institute of Pathogenic Biology, School of Basic Medical Sciences, Lanzhou University, Lanzhou 730000, China.
| | - Yi-Wei Jiang
- Spinal Surgery Department, Affiliated Hospital of Gansu University of Chinese Medicines, Lanzhou 730020, China.
| | - Jun-Qiu Xie
- Institute of Pathogenic Biology, School of Basic Medical Sciences, Lanzhou University, Lanzhou 730000, China.
| | - Xiao-Gang Zhang
- Spinal Surgery Department, Affiliated Hospital of Gansu University of Chinese Medicines, Lanzhou 730020, China.
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15
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Liu HX, Chen K, Yuan Y, Xu ZF, Tan HB, Qiu SX. Rhodomentones A and B, novel meroterpenoids with unique NMR characteristics from Rhodomyrtus tomentosa. Org Biomol Chem 2016; 14:7354-60. [DOI: 10.1039/c6ob01215a] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Two novel meroterpenoids were isolated from Rhodomyrtus tomentosa. Their structures with unique NMR characteristics were determined by extensive spectroscopic analysis, single-crystal X-ray diffraction, quantum molecular calculation, chemical transformation as well as total synthesis.
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Affiliation(s)
- Hong-Xin Liu
- Program for Natural Products Chemical Biology
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization
- South China Botanical Garden
- Chinese Academy of Sciences
- Guangzhou 510650
| | - Kai Chen
- School of Chemistry and Chemical Engineering
- South China University of Technology
- Guangzhou 510640
- China
| | - Yao Yuan
- Program for Natural Products Chemical Biology
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization
- South China Botanical Garden
- Chinese Academy of Sciences
- Guangzhou 510650
| | - Zhi-Fang Xu
- Program for Natural Products Chemical Biology
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization
- South China Botanical Garden
- Chinese Academy of Sciences
- Guangzhou 510650
| | - Hai-Bo Tan
- Program for Natural Products Chemical Biology
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization
- South China Botanical Garden
- Chinese Academy of Sciences
- Guangzhou 510650
| | - Sheng-Xiang Qiu
- Program for Natural Products Chemical Biology
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization
- South China Botanical Garden
- Chinese Academy of Sciences
- Guangzhou 510650
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16
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A Commensal Strain of Staphylococcus epidermidis Overexpresses Membrane Proteins Associated with Pathogenesis When Grown in Biofilms. J Membr Biol 2015; 248:431-42. [PMID: 25837994 DOI: 10.1007/s00232-015-9801-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Accepted: 03/26/2015] [Indexed: 11/26/2022]
Abstract
Staphylococcus epidermidis has emerged as one of the major nosocomial pathogens associated with infections of implanted medical devices. The most important factor in the pathogenesis of these infections is the formation of bacterial biofilms. Bacteria grown in biofilms are more resistant to antibiotics and to the immune defence system than planktonic bacteria. In these infections, the antimicrobial therapy usually fails and the removal of the biofilm-coated implanted device is the only effective solution. In this study, three proteomic approaches were performed to investigate membrane proteins associated to biofilm formation: (i) sample fractionation by gel electrophoresis, followed by isotopic labelling and LC-MS/MS analysis, (ii) in-solution sample preparation, followed by isotopic labelling and LC-MS/MS analysis and (iii) in-solution sample preparation and label-free LC-MS/MS analysis. We found that the commensal strain S. epidermidis CECT 231 grown in biofilms expressed higher levels of five membrane and membrane-associated proteins involved in pathogenesis: accumulation-associated protein, staphylococcal secretory antigen, signal transduction protein TRAP, ribonuclease Y and phenol soluble modulin beta 1 when compared with bacteria grown under planktonic conditions. These results indicate that a commensal strain can acquire a pathogenic phenotype depending on the mode of growth.
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17
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Shou Q, Smith JE, Mon H, Brkljača Z, Smith AS, Smith DM, Griesser HJ, Wohlmuth H. Rhodomyrtals A–D, four unusual phloroglucinol-sesquiterpene adducts from Rhodomyrtus psidioides. RSC Adv 2014. [DOI: 10.1039/c4ra00154k] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Four unusual phloroglucinol-sesquiterpene adducts, rhodomyrtals A–D (1–4), representing two unprecendented carbon frameworks of phloroglucinol coupled eudesmane with the linkage at C-12′, were isolated from Rhodomyrtus psidioides.
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Affiliation(s)
- Qingyao Shou
- Southern Cross Plant Science
- Southern Cross University
- Lismore NSW 2480, Australia
| | - Joshua E. Smith
- Southern Cross Plant Science
- Southern Cross University
- Lismore NSW 2480, Australia
| | - Htwe Mon
- Ian Wark Research Institute
- University of South Australia
- Mawson Lakes SA 5095, Australia
| | - Zlatko Brkljača
- Institute for Theoretical Physics
- Friedrich Alexander University Erlangen-Nürnberg
- Erlangen, Germany
| | - Ana-Sunčana Smith
- Institute for Theoretical Physics
- Friedrich Alexander University Erlangen-Nürnberg
- Erlangen, Germany
- Ruđer Bošković Institute
- 10000 Zagreb, Croatia
| | - David M. Smith
- Institute for Theoretical Physics
- Friedrich Alexander University Erlangen-Nürnberg
- Erlangen, Germany
- Ruđer Bošković Institute
- 10000 Zagreb, Croatia
| | - Hans J. Griesser
- Ian Wark Research Institute
- University of South Australia
- Mawson Lakes SA 5095, Australia
| | - Hans Wohlmuth
- Southern Cross Plant Science
- Southern Cross University
- Lismore NSW 2480, Australia
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Leejae S, Taylor PW, Voravuthikunchai SP. Antibacterial mechanisms of rhodomyrtone against important hospital-acquired antibiotic-resistant pathogenic bacteria. J Med Microbiol 2013; 62:78-85. [DOI: 10.1099/jmm.0.049205-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Sukanlaya Leejae
- Department of Microbiology and Natural Products Research Center, Faculty of Science, Prince of Songkla University, Songkhla 90112, Thailand
| | | | - Supayang Piyawan Voravuthikunchai
- Department of Microbiology and Natural Products Research Center, Faculty of Science, Prince of Songkla University, Songkhla 90112, Thailand
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20
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Leejae S, Hasap L, Voravuthikunchai SP. Inhibition of staphyloxanthin biosynthesis in Staphylococcus aureus by rhodomyrtone, a novel antibiotic candidate. J Med Microbiol 2012; 62:421-428. [PMID: 23242641 DOI: 10.1099/jmm.0.047316-0] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Staphyloxanthin is the eponymous feature of the human pathogen Staphylococcus aureus, and the pigment promotes resistance to reactive oxygen species and host neutrophil-based killing. To probe the possible use of rhodomyrtone isolated from Rhodomyrtus tomentosa (Aiton) Hassk. leaves to inhibit pigment production in S. aureus, experiments were carried out to compare pigment production and the susceptibility of rhodomyrtone-treated S. aureus and untreated cells to oxidants in vitro. In addition, we observed the innate immune clearance of S. aureus after incubation with rhodomyrtone using an ex vivo assay system - human whole-blood survival. The results indicated that rhodomyrtone-treated S. aureus exhibited reduced pigmentation, and that rhodomyrtone treatment led to a dose-dependent increase in the susceptibility of the pathogen to H(2)O(2) and singlet oxygen killing. Consequently, the survival ability of the treated organisms decreased in freshly isolated human whole blood due to less carotenoid pigment to act as an antioxidant scavenger. Rhodomyrtone may be acting via effects on DnaK and/or σ(B), resulting in many additional effects on bacterial virulence.
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Affiliation(s)
- Sukanlaya Leejae
- Department of Microbiology and Natural Products Research Center, Faculty of Science, Prince of Songkla University, Songkhla 90112, Thailand
| | - Laila Hasap
- Department of Microbiology and Natural Products Research Center, Faculty of Science, Prince of Songkla University, Songkhla 90112, Thailand
| | - Supayang Piyawan Voravuthikunchai
- Department of Microbiology and Natural Products Research Center, Faculty of Science, Prince of Songkla University, Songkhla 90112, Thailand
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21
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Antibacterial Activity of Rhodomyrtus tomentosa (Aiton) Hassk. Leaf Extract against Clinical Isolates of Streptococcus pyogenes. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2012; 2012:697183. [PMID: 22973404 PMCID: PMC3438885 DOI: 10.1155/2012/697183] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/03/2012] [Revised: 07/26/2012] [Accepted: 07/31/2012] [Indexed: 11/18/2022]
Abstract
Ethanol extract of Rhodomyrtus tomentosa (Aiton) Hassk. leaf was evaluated for antibacterial activity against 47 clinical isolates of Streptococcus pyogenes. The extract exhibited good anti-S. pyogenes activity against all the tested isolates with similar minimum inhibitory concentration (MIC, 3.91-62.5 μg mL(-1)) and minimum bactericidal concentration (MBC, 3.91-62.5 μg mL(-1)) ranges. No surviving cells were detected at 16 h after treatment with 8 × MIC of the extract. The extract-treated cells demonstrated no lysis and cytoplasmic leakage through the bacterial membrane. Electron micrographs further revealed that the extract did not cause any dramatic changes on the treated cells. Rhodomyrtone, an isolated compound, exhibited good anti-S. pyogenes activity (14 isolates), expressed very low MIC (0.39-1.56 μg mL(-1)) and MBC (0.39-1.56 μg mL(-1)) values. Rhodomyrtus tomentosa leaf extract and rhodomyrtone displayed promising antibacterial activity against clinical isolates of S. pyogenes.
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22
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Synthesis and structure–activity relationship of rhodomyrtone derivatives as antibacterial agent. CHINESE CHEM LETT 2012. [DOI: 10.1016/j.cclet.2012.06.040] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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