TY - JOUR
T1 - Expression analysis of up-regulated genes responding to plumbagin in Escherichia coli
AU - Chen, Jenn Wei
AU - Sun, Chang Ming
AU - Sheng, Wei Lun
AU - Wang, Yu Chen
AU - Syu, Wan
PY - 2006/1
Y1 - 2006/1
N2 - Plumbagin is found in many medicinal plants and has been reported to have antimicrobial activities. We examined the molecular responses of Escherichia coli to plumbagin by using a proteomic approach to search for bacterial genes up-regulated by the drug. The protein profile obtained was compared with that of E. coli without the plumbagin treatment. Subsequent analyses of the induced proteins by mass spectroscopy identified several up-regulated genes, including ygfZ, whose function has not been defined. Analyses of the 5′-flanking sequences indicate that most of these genes contain a marbox-like stretch, and several of them are categorized as members of the mar/sox regulon. Representatives of these genes were cloned into plasmids, and the marbox-like sequences were modified by site-directed mutagenesis. It was proven that mutations in these regions substantially repressed the level of proteins encoded by the downstream genes. Furthermore, plumbagin's early effect was demonstrated to robustly induce SoxS rather than MarA, an observation distinctly different from that seen with sodium salicylate.
AB - Plumbagin is found in many medicinal plants and has been reported to have antimicrobial activities. We examined the molecular responses of Escherichia coli to plumbagin by using a proteomic approach to search for bacterial genes up-regulated by the drug. The protein profile obtained was compared with that of E. coli without the plumbagin treatment. Subsequent analyses of the induced proteins by mass spectroscopy identified several up-regulated genes, including ygfZ, whose function has not been defined. Analyses of the 5′-flanking sequences indicate that most of these genes contain a marbox-like stretch, and several of them are categorized as members of the mar/sox regulon. Representatives of these genes were cloned into plasmids, and the marbox-like sequences were modified by site-directed mutagenesis. It was proven that mutations in these regions substantially repressed the level of proteins encoded by the downstream genes. Furthermore, plumbagin's early effect was demonstrated to robustly induce SoxS rather than MarA, an observation distinctly different from that seen with sodium salicylate.
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U2 - 10.1128/JB.188.2.456-463.2006
DO - 10.1128/JB.188.2.456-463.2006
M3 - Article
C2 - 16385035
AN - SCOPUS:30744438630
SN - 0021-9193
VL - 188
SP - 456
EP - 463
JO - Journal of Bacteriology
JF - Journal of Bacteriology
IS - 2
ER -