Metabolites of the "smoke tree", Dalea spinosa, potentiate antibiotic activity against multidrug-resistant Staphylococcus aureus.
Two new 2-arylbenzofuran aldehydes (1 and 2) and three known phenolic compounds (3-5) were isolated from organic extracts of Dalea spinosa. These compounds were evaluated for their intrinsic antimicrobial activity and their ability to perform as multidrug-resistance inhibitors by potentiating the activity of known antimicrobials against a variety of pathogenic microorganisms. Compound 1 and its acetate derivative 6 exhibited no direct antimicrobial activity but enhanced the effect of the weak plant antimicrobial berberine when tested against Staphylococcus aureus. Additional potentiation assays with S. aureus overexpression and knockout isogenic efflux mutants for the NorA pump were done in order to assess whether the potentiating effects were associated with inhibition of this known pump mechanism.
Belofsky
Gil
G
Department of Chemistry and Biochemistry, The University of Tulsa, Tulsa, Oklahoma 74101, USA. gbelofsky@efficas.com
Carreno
Roberto
R
Lewis
Kim
K
Ball
Anthony
A
Casadei
Gabriele
G
Tegos
George P
GP
D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D001572:Benzofurans / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D001599:Berberine / Q000494:pharmacology; D003889:Desert Climate; D018432:Drug Resistance, Multiple; D007887:Fabaceae / Q000737:chemistry*; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D010946:Plants, Medicinal / Q000737:chemistry*; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000235:genetics
D000900:Anti-Bacterial Agents; D001572:Benzofurans; C508821:spinosan A; C508822:spinosan B; D001599:Berberine