Novel inhibitory activity of the Staphylococcus aureus NorA efflux pump by a kaempferol rhamnoside isolated from Persea lingue Nees

Jes Gitz Holler; Søren Brøgger Christensen; Hans-Christian Slotved; Hasse Bonde Rasmussen; A. Guzman; Carl Erik Olsen; Bent Petersen; Per Mølgaard

doi:10.1093/jac/dks005

Novel inhibitory activity of the Staphylococcus aureus NorA efflux pump by a kaempferol rhamnoside isolated from Persea lingue Nees

Jes Gitz Holler, Søren Brøgger Christensen, Hans-Christian Slotved, Hasse Bonde Rasmussen, A. Guzman, Carl Erik Olsen, Bent Petersen, Per Mølgaard

74 Citations (Scopus)

Abstract

Objectives: To isolate a plant-derived compound with efflux inhibitory activity towards the NorA transporter of Staphylococcus aureus. Methods: Bioassay-guided isolation was used, with inhibition of ethidium bromide efflux via NorA as a guide. Characterization of activity was carried out using MIC determination and potentiation studies of a fluoroquinolone antibiotic in combination with the isolated compound. Everted membrane vesicles of Escherichia coli cells enriched with NorA were prepared to study efflux inhibitory activity in an isolated manner. Results: The ethanolic extract of Persea lingue was subjected to bioassay-guided fractionation and led to the isolation of the known compound kaempferol-3-O-α-l-(2,4-bis-E-p-coumaroyl)rhamnoside (compound 1). Evaluation of the dose-response relationship of compound 1 showed that ethidium bromide efflux was inhibited, with an IC ₅₀ value of 2 μM. The positive control, reserpine, was found to have an IC ₅₀ value of 9 μM. Compound 1 also inhibited NorA in enriched everted membrane vesicles of E. coli. Potentiation studies revealed that compound 1 at 1.56 mg/L synergistically increased the antimicrobial activity of ciprofloxacin 8-fold against a NorA overexpresser, and the synergistic activity was exerted at a fourth of the concentration necessary for reserpine. Compound 1 was not found to exert a synergistic effect on ciprofloxacin against a norA deletion mutant. The 2,3-coumaroyl isomer of compound 1 has been shown previously not to cause acute toxicity in mice at 20 mg/kg/day. Conclusions: Our results show that compound 1 acts through inhibition of the NorA efflux pump. Combination of compound 1 with subinhibitory concentrations of ciprofloxacin renders a wild-type more susceptible and a NorA overexpresser S. aureus susceptible.

Original language	English
Journal	Journal of Antimicrobial Chemotherapy
Volume	67
Issue number	5
Pages (from-to)	1138 - 1144
Number of pages	7
ISSN	0305-7453
DOIs	https://doi.org/10.1093/jac/dks005
Publication status	Published - May 2012

Access to Document

10.1093/jac/dks005

Cite this

Novel inhibitory activity of the Staphylococcus aureus NorA efflux pump by a kaempferol rhamnoside isolated from Persea lingue Nees. / Holler, Jes Gitz; Christensen, Søren Brøgger; Slotved, Hans-Christian et al.
In: Journal of Antimicrobial Chemotherapy, Vol. 67, No. 5, 05.2012, p. 1138 - 1144.

Research output: Contribution to journal › Journal article › Research › peer-review

@article{729eb22708f14e9ab66c8373b06c6ad7,

title = "Novel inhibitory activity of the Staphylococcus aureus NorA efflux pump by a kaempferol rhamnoside isolated from Persea lingue Nees",

abstract = "Objectives: To isolate a plant-derived compound with efflux inhibitory activity towards the NorA transporter of Staphylococcus aureus. Methods: Bioassay-guided isolation was used, with inhibition of ethidium bromide efflux via NorA as a guide. Characterization of activity was carried out using MIC determination and potentiation studies of a fluoroquinolone antibiotic in combination with the isolated compound. Everted membrane vesicles of Escherichia coli cells enriched with NorA were prepared to study efflux inhibitory activity in an isolated manner. Results: The ethanolic extract of Persea lingue was subjected to bioassay-guided fractionation and led to the isolation of the known compound kaempferol-3-O-α-l-(2,4-bis-E-p-coumaroyl)rhamnoside (compound 1). Evaluation of the dose-response relationship of compound 1 showed that ethidium bromide efflux was inhibited, with an IC 50 value of 2 μM. The positive control, reserpine, was found to have an IC 50 value of 9 μM. Compound 1 also inhibited NorA in enriched everted membrane vesicles of E. coli. Potentiation studies revealed that compound 1 at 1.56 mg/L synergistically increased the antimicrobial activity of ciprofloxacin 8-fold against a NorA overexpresser, and the synergistic activity was exerted at a fourth of the concentration necessary for reserpine. Compound 1 was not found to exert a synergistic effect on ciprofloxacin against a norA deletion mutant. The 2,3-coumaroyl isomer of compound 1 has been shown previously not to cause acute toxicity in mice at 20 mg/kg/day. Conclusions: Our results show that compound 1 acts through inhibition of the NorA efflux pump. Combination of compound 1 with subinhibitory concentrations of ciprofloxacin renders a wild-type more susceptible and a NorA overexpresser S. aureus susceptible.",

author = "Holler, {Jes Gitz} and Christensen, {S{\o}ren Br{\o}gger} and Hans-Christian Slotved and Rasmussen, {Hasse Bonde} and A. Guzman and Olsen, {Carl Erik} and Bent Petersen and Per M{\o}lgaard",

year = "2012",

month = may,

doi = "10.1093/jac/dks005",

language = "English",

volume = "67",

pages = "1138 -- 1144",

journal = "Journal of Antimicrobial Chemotherapy",

issn = "0305-7453",

publisher = "Oxford University Press",

number = "5",

}

TY - JOUR

T1 - Novel inhibitory activity of the Staphylococcus aureus NorA efflux pump by a kaempferol rhamnoside isolated from Persea lingue Nees

AU - Holler, Jes Gitz

AU - Christensen, Søren Brøgger

AU - Slotved, Hans-Christian

AU - Rasmussen, Hasse Bonde

AU - Guzman, A.

AU - Olsen, Carl Erik

AU - Petersen, Bent

AU - Mølgaard, Per

PY - 2012/5

Y1 - 2012/5

N2 - Objectives: To isolate a plant-derived compound with efflux inhibitory activity towards the NorA transporter of Staphylococcus aureus. Methods: Bioassay-guided isolation was used, with inhibition of ethidium bromide efflux via NorA as a guide. Characterization of activity was carried out using MIC determination and potentiation studies of a fluoroquinolone antibiotic in combination with the isolated compound. Everted membrane vesicles of Escherichia coli cells enriched with NorA were prepared to study efflux inhibitory activity in an isolated manner. Results: The ethanolic extract of Persea lingue was subjected to bioassay-guided fractionation and led to the isolation of the known compound kaempferol-3-O-α-l-(2,4-bis-E-p-coumaroyl)rhamnoside (compound 1). Evaluation of the dose-response relationship of compound 1 showed that ethidium bromide efflux was inhibited, with an IC 50 value of 2 μM. The positive control, reserpine, was found to have an IC 50 value of 9 μM. Compound 1 also inhibited NorA in enriched everted membrane vesicles of E. coli. Potentiation studies revealed that compound 1 at 1.56 mg/L synergistically increased the antimicrobial activity of ciprofloxacin 8-fold against a NorA overexpresser, and the synergistic activity was exerted at a fourth of the concentration necessary for reserpine. Compound 1 was not found to exert a synergistic effect on ciprofloxacin against a norA deletion mutant. The 2,3-coumaroyl isomer of compound 1 has been shown previously not to cause acute toxicity in mice at 20 mg/kg/day. Conclusions: Our results show that compound 1 acts through inhibition of the NorA efflux pump. Combination of compound 1 with subinhibitory concentrations of ciprofloxacin renders a wild-type more susceptible and a NorA overexpresser S. aureus susceptible.

AB - Objectives: To isolate a plant-derived compound with efflux inhibitory activity towards the NorA transporter of Staphylococcus aureus. Methods: Bioassay-guided isolation was used, with inhibition of ethidium bromide efflux via NorA as a guide. Characterization of activity was carried out using MIC determination and potentiation studies of a fluoroquinolone antibiotic in combination with the isolated compound. Everted membrane vesicles of Escherichia coli cells enriched with NorA were prepared to study efflux inhibitory activity in an isolated manner. Results: The ethanolic extract of Persea lingue was subjected to bioassay-guided fractionation and led to the isolation of the known compound kaempferol-3-O-α-l-(2,4-bis-E-p-coumaroyl)rhamnoside (compound 1). Evaluation of the dose-response relationship of compound 1 showed that ethidium bromide efflux was inhibited, with an IC 50 value of 2 μM. The positive control, reserpine, was found to have an IC 50 value of 9 μM. Compound 1 also inhibited NorA in enriched everted membrane vesicles of E. coli. Potentiation studies revealed that compound 1 at 1.56 mg/L synergistically increased the antimicrobial activity of ciprofloxacin 8-fold against a NorA overexpresser, and the synergistic activity was exerted at a fourth of the concentration necessary for reserpine. Compound 1 was not found to exert a synergistic effect on ciprofloxacin against a norA deletion mutant. The 2,3-coumaroyl isomer of compound 1 has been shown previously not to cause acute toxicity in mice at 20 mg/kg/day. Conclusions: Our results show that compound 1 acts through inhibition of the NorA efflux pump. Combination of compound 1 with subinhibitory concentrations of ciprofloxacin renders a wild-type more susceptible and a NorA overexpresser S. aureus susceptible.

U2 - 10.1093/jac/dks005

DO - 10.1093/jac/dks005

M3 - Journal article

C2 - 22311936

SN - 0305-7453

VL - 67

SP - 1138

EP - 1144

JO - Journal of Antimicrobial Chemotherapy

JF - Journal of Antimicrobial Chemotherapy

IS - 5

ER -

Novel inhibitory activity of the Staphylococcus aureus NorA efflux pump by a kaempferol rhamnoside isolated from Persea lingue Nees

Abstract

Access to Document

Fingerprint

Cite this