Iron and salicylate induction of cytochrome P450BM-1 in Bacillus megaterium.
The effects of iron and salicylate on the expression of cytochrome P450s in Bacillus megaterium were investigated in this report. Immunoblot analysis showed that the addition of 4 mM ferric iron or 10 mM salicylate to the culture medium resulted in a significant increase in the P450BM-1 level, while the same condition had little effect on P450BM-3 expression. Substantial induction of chloramphenicol acetyltransferase (CAT) activity by iron and salicylate in B. megaterium cells bearing a P450BM-1 promoter-cat transcriptional fusion vector suggests that the induction of P450BM-1 by iron and salicylate occurs at the transcriptional level. Unexpectedly, in contrast to the bm1P1-dependent induction of P450BM-1 by pentobarbital, disruption of bm1P1 gene did not affect induction of P450BM-1 by iron and salicylate. This result suggests that the induction of P450BM-1 by iron and salicylate occurs by a bm1P1-independent mechanism. To our knowledge, this is the first example of an iron-regulated cytochrome P450 gene in prokaryotes.
Shaw
G C
GC
Institute of Biochemistry, School of Life Science, National Yang-Ming University, Taipei, Taiwan, Republic of China.
Kao
H S
HS
Sung
C C
CC
Chiang
A N
AN
D001410:Bacillus megaterium / Q000201:enzymology*; D003577:Cytochrome P-450 Enzyme System / Q000096:biosynthesis*; D004305:Dose-Response Relationship, Drug; D004790:Enzyme Induction / Q000187:drug effects; D015151:Immunoblotting; D007501:Iron / Q000494:pharmacology*; D012459:Salicylates / Q000494:pharmacology*
D012459:Salicylates; D003577:Cytochrome P-450 Enzyme System; D007501:Iron