The antibacterial efficacy of an aceraceous plant [Shantung maple (Acer truncatum Bunge)] may be related to inhibition of bacterial beta-oxoacyl-acyl carrier protein reductase (FabG).
Polyphenols, including flavonoids, are the major components of the extracts from aceraceous plants. They possess remarkable antibacterial and antitumour activity. Our study focused on whether the inhibition of the bacterial type II fatty acid synthesis system is the mechanism for the antibacterial effect of the related plant polyphenols. Extracts obtained from the fallen leaves of the Shantung maple (Acer truncatum Bunge) using different solvents, and the related pure compound PGG (1,2,3,4,6-penta-O-galloyl-beta-D-glucose), potently inhibited the FabG (beta-oxoacyl-ACP reductase) steps in the fatty-acid-elongation cycle with the IC(50) values between 0.9 and 7.2 microg/ml. An ethyl acetate extract appeared to inhibit FabG reductase in a mixed manner with NADPH, as did PGG with NADPH, demonstrating that they interfered with the binding of the cofactor to the enzyme. Gram-positive and Gram-negative bacteria and some fungi were used to evaluate the antibacterial abilities of different extract samples. The experiments showed that a higher polyphenol content of the extracts led to a more potent inhibitory capacity against FabG, thus enhancing the antibacterial efficacy.
Zhang
Feng
F
Department of Chemical Biology, School of Chemical Biology and Pharmaceutical Sciences, Capital Medical University, Beijing 100069, People's Republic of China.
Luo
Shi-Yun
SY
Ye
Yan-Bin
YB
Zhao
Wen-Hua
WH
Sun
Xu-Guang
XG
Wang
Zhi-Qun
ZQ
Li
Ran
R
Sun
Ying-Hui
YH
Tian
Wei-Xi
WX
Zhang
Ying-Xia
YX
D031002:Acer / Q000737:chemistry*; D000429:Alcohol Oxidoreductases / Q000037:antagonists & inhibitors* / Q000737:chemistry / Q000302:isolation & purification; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D001665:Binding Sites; D004305:Dose-Response Relationship, Drug; D004365:Drugs, Chinese Herbal / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D004789:Enzyme Activation / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D004926:Escherichia coli / Q000187:drug effects / Q000201:enzymology*; D005658:Fungi / Q000187:drug effects; D006090:Gram-Negative Bacteria / Q000187:drug effects; D006094:Gram-Positive Bacteria / Q000187:drug effects; D020128:Inhibitory Concentration 50; D007700:Kinetics; D008826:Microbial Sensitivity Tests; D018515:Plant Leaves / Q000737:chemistry; D013045:Species Specificity; D013329:Structure-Activity Relationship; D013997:Time Factors
D000900:Anti-Bacterial Agents; D004365:Drugs, Chinese Herbal; D004791:Enzyme Inhibitors; D000429:Alcohol Oxidoreductases; C023744:acetoacetyl-CoA reductase