A quinolinol-based small molecule with anti-MRSA activity that targets bacterial membrane and promotes fermentative metabolism

Dhanalakshmi R. Nair, Ji Chen, João M. Monteiro, Michaele Josten, Mariana G. Pinho, Hans Georg Sahl, Jimmy Wu, Ambrose Cheung

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

In a loss-of-viability screen of small molecules against methicillin-resistant Staphylococcus aureus (MRSA) USA300, we found a small molecule, designated DNAC-2, which has an MIC of 8 μg ml1. DNAC-2 is a quinolinol derivative that is bactericidal at 2X MIC. Macromolecular synthesis assays at 2 × MIC of DNAC-2 revealed inhibition of DNA, cell wall, RNA and protein synthesis within fifteen to thirty minutes of treatment when compared to the untreated control. Transmission electron microscopy of DNAC-2-treated cells revealed a significantly thicker cell wall and impaired daughter cell separation. Exposure of USA300 cells to 1 × MIC of DNAC-2 resulted in mislocalization of PBP2 away from the septum in an FtsZ-independent manner. In addition, membrane localization with FM4-64, as well as depolarization study with DiOC 2 and lipophilic cation TPP+ displayed membrane irregularities and rapid membrane depolarization, respectively, in DNAC-2-treated cells vs -untreated control. However, DNAC-2 exhibited almost no toxicity toward eukaryotic membranes. Notably, DNAC-2 drives energy generation toward substrate level phosphorylation and the bacteria become more sensitive to DNAC-2 under anaerobic conditions. We propose that DNAC-2 affects USA300 by targeting the membrane, leading to partial membrane depolarization and subsequently affecting aerobic respiration and energy-dependent functional organization of macromolecular biosynthetic pathways. The multiple effects may have the desirable consequence of limiting the emergence of resistance to DNAC-2.

Original languageEnglish
Pages (from-to)1009-1019
Number of pages11
JournalJournal of Antibiotics
Volume70
Issue number10
DOIs
Publication statusPublished - 1 Oct 2017

Fingerprint

Hydroxyquinolines
Methicillin-Resistant Staphylococcus aureus
Membranes
Cell Wall
Cell Separation
Biosynthetic Pathways
Transmission Electron Microscopy
Cations
Respiration
Phosphorylation
RNA
Bacteria
DNA

Cite this

Nair, Dhanalakshmi R. ; Chen, Ji ; Monteiro, João M. ; Josten, Michaele ; Pinho, Mariana G. ; Sahl, Hans Georg ; Wu, Jimmy ; Cheung, Ambrose. / A quinolinol-based small molecule with anti-MRSA activity that targets bacterial membrane and promotes fermentative metabolism. In: Journal of Antibiotics. 2017 ; Vol. 70, No. 10. pp. 1009-1019.
@article{7364e6c9c22b4c2b989b5a4ffc6d2922,
title = "A quinolinol-based small molecule with anti-MRSA activity that targets bacterial membrane and promotes fermentative metabolism",
abstract = "In a loss-of-viability screen of small molecules against methicillin-resistant Staphylococcus aureus (MRSA) USA300, we found a small molecule, designated DNAC-2, which has an MIC of 8 μg ml1. DNAC-2 is a quinolinol derivative that is bactericidal at 2X MIC. Macromolecular synthesis assays at 2 × MIC of DNAC-2 revealed inhibition of DNA, cell wall, RNA and protein synthesis within fifteen to thirty minutes of treatment when compared to the untreated control. Transmission electron microscopy of DNAC-2-treated cells revealed a significantly thicker cell wall and impaired daughter cell separation. Exposure of USA300 cells to 1 × MIC of DNAC-2 resulted in mislocalization of PBP2 away from the septum in an FtsZ-independent manner. In addition, membrane localization with FM4-64, as well as depolarization study with DiOC 2 and lipophilic cation TPP+ displayed membrane irregularities and rapid membrane depolarization, respectively, in DNAC-2-treated cells vs -untreated control. However, DNAC-2 exhibited almost no toxicity toward eukaryotic membranes. Notably, DNAC-2 drives energy generation toward substrate level phosphorylation and the bacteria become more sensitive to DNAC-2 under anaerobic conditions. We propose that DNAC-2 affects USA300 by targeting the membrane, leading to partial membrane depolarization and subsequently affecting aerobic respiration and energy-dependent functional organization of macromolecular biosynthetic pathways. The multiple effects may have the desirable consequence of limiting the emergence of resistance to DNAC-2.",
author = "Nair, {Dhanalakshmi R.} and Ji Chen and Monteiro, {Jo{\~a}o M.} and Michaele Josten and Pinho, {Mariana G.} and Sahl, {Hans Georg} and Jimmy Wu and Ambrose Cheung",
year = "2017",
month = "10",
day = "1",
doi = "10.1038/ja.2017.79",
language = "English",
volume = "70",
pages = "1009--1019",
journal = "Journal of Antibiotics",
issn = "0021-8820",
publisher = "Japan Antibiotics Res Assoc",
number = "10",

}

A quinolinol-based small molecule with anti-MRSA activity that targets bacterial membrane and promotes fermentative metabolism. / Nair, Dhanalakshmi R.; Chen, Ji; Monteiro, João M.; Josten, Michaele; Pinho, Mariana G.; Sahl, Hans Georg; Wu, Jimmy; Cheung, Ambrose.

In: Journal of Antibiotics, Vol. 70, No. 10, 01.10.2017, p. 1009-1019.

Research output: Contribution to journalArticle

TY - JOUR

T1 - A quinolinol-based small molecule with anti-MRSA activity that targets bacterial membrane and promotes fermentative metabolism

AU - Nair, Dhanalakshmi R.

AU - Chen, Ji

AU - Monteiro, João M.

AU - Josten, Michaele

AU - Pinho, Mariana G.

AU - Sahl, Hans Georg

AU - Wu, Jimmy

AU - Cheung, Ambrose

PY - 2017/10/1

Y1 - 2017/10/1

N2 - In a loss-of-viability screen of small molecules against methicillin-resistant Staphylococcus aureus (MRSA) USA300, we found a small molecule, designated DNAC-2, which has an MIC of 8 μg ml1. DNAC-2 is a quinolinol derivative that is bactericidal at 2X MIC. Macromolecular synthesis assays at 2 × MIC of DNAC-2 revealed inhibition of DNA, cell wall, RNA and protein synthesis within fifteen to thirty minutes of treatment when compared to the untreated control. Transmission electron microscopy of DNAC-2-treated cells revealed a significantly thicker cell wall and impaired daughter cell separation. Exposure of USA300 cells to 1 × MIC of DNAC-2 resulted in mislocalization of PBP2 away from the septum in an FtsZ-independent manner. In addition, membrane localization with FM4-64, as well as depolarization study with DiOC 2 and lipophilic cation TPP+ displayed membrane irregularities and rapid membrane depolarization, respectively, in DNAC-2-treated cells vs -untreated control. However, DNAC-2 exhibited almost no toxicity toward eukaryotic membranes. Notably, DNAC-2 drives energy generation toward substrate level phosphorylation and the bacteria become more sensitive to DNAC-2 under anaerobic conditions. We propose that DNAC-2 affects USA300 by targeting the membrane, leading to partial membrane depolarization and subsequently affecting aerobic respiration and energy-dependent functional organization of macromolecular biosynthetic pathways. The multiple effects may have the desirable consequence of limiting the emergence of resistance to DNAC-2.

AB - In a loss-of-viability screen of small molecules against methicillin-resistant Staphylococcus aureus (MRSA) USA300, we found a small molecule, designated DNAC-2, which has an MIC of 8 μg ml1. DNAC-2 is a quinolinol derivative that is bactericidal at 2X MIC. Macromolecular synthesis assays at 2 × MIC of DNAC-2 revealed inhibition of DNA, cell wall, RNA and protein synthesis within fifteen to thirty minutes of treatment when compared to the untreated control. Transmission electron microscopy of DNAC-2-treated cells revealed a significantly thicker cell wall and impaired daughter cell separation. Exposure of USA300 cells to 1 × MIC of DNAC-2 resulted in mislocalization of PBP2 away from the septum in an FtsZ-independent manner. In addition, membrane localization with FM4-64, as well as depolarization study with DiOC 2 and lipophilic cation TPP+ displayed membrane irregularities and rapid membrane depolarization, respectively, in DNAC-2-treated cells vs -untreated control. However, DNAC-2 exhibited almost no toxicity toward eukaryotic membranes. Notably, DNAC-2 drives energy generation toward substrate level phosphorylation and the bacteria become more sensitive to DNAC-2 under anaerobic conditions. We propose that DNAC-2 affects USA300 by targeting the membrane, leading to partial membrane depolarization and subsequently affecting aerobic respiration and energy-dependent functional organization of macromolecular biosynthetic pathways. The multiple effects may have the desirable consequence of limiting the emergence of resistance to DNAC-2.

UR - http://www.scopus.com/inward/record.url?scp=85030124954&partnerID=8YFLogxK

U2 - 10.1038/ja.2017.79

DO - 10.1038/ja.2017.79

M3 - Article

VL - 70

SP - 1009

EP - 1019

JO - Journal of Antibiotics

JF - Journal of Antibiotics

SN - 0021-8820

IS - 10

ER -