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Bacillus subtilis HemY is a peripheral membrane protein essential for protoheme IX synthesis which can oxidize coproporphyrinogen III and protoporphyrinogen IX

Hansson, Mats LU and Hederstedt, Lars LU (1994) In Journal of Bacteriology 176(19). p.5962-5970
Abstract
The hemY gene of the Bacillus subtilis hemEHY operon is essential for protoheme IX biosynthesis. Two previously isolated hemY mutations were sequenced. Both mutations are deletions affecting the hemY reading frame, and they cause the accumulation of coproporphyrinogen III or coproporphyrin III in the growth medium and the accumulation of trace amounts of other porphyrinogens or porphyrins intracellularly. HemY was found to be a 53-kDa peripheral membrane-bound protein. In agreement with recent findings by Dailey et al. (J. Biol. Chem. 269:813-815, 1994) B. subtilis HemY protein synthesized in Escherichia coli oxidized coproporphyrinogen III and protoporphyrinogen IX to coproporphyrin and protoporphyrin, respectively. The protein is not a... (More)
The hemY gene of the Bacillus subtilis hemEHY operon is essential for protoheme IX biosynthesis. Two previously isolated hemY mutations were sequenced. Both mutations are deletions affecting the hemY reading frame, and they cause the accumulation of coproporphyrinogen III or coproporphyrin III in the growth medium and the accumulation of trace amounts of other porphyrinogens or porphyrins intracellularly. HemY was found to be a 53-kDa peripheral membrane-bound protein. In agreement with recent findings by Dailey et al. (J. Biol. Chem. 269:813-815, 1994) B. subtilis HemY protein synthesized in Escherichia coli oxidized coproporphyrinogen III and protoporphyrinogen IX to coproporphyrin and protoporphyrin, respectively. The protein is not a general porphyrinogen oxidase since it did not oxidize uroporphyrinogen III. The apparent specificity constant, kcat/Km, for HemY was found to be about 12-fold higher with coproporphyrinogen III as a substrate compared with protoporphyrinogen IX as a substrate. The protoporphyrinogen IX oxidase activity is consistent with the function of HemY in a late step of protoheme IX biosynthesis, i.e., HemY catalyzes the penultimate step of the pathway. However, the efficient coproporphyrinogen III to coproporphyrin oxidase activity is unexplained in the current view of protoheme IX biosynthesis. (Less)
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published
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keywords
Porphyrinogens/*metabolism, Oxidation-Reduction, Mutation, Molecular Sequence Data, Membrane Proteins/biosynthesis/*genetics, Kinetics, Heme/*biosynthesis, Coproporphyrinogens/metabolism, Molecular, Cloning, Base Sequence, Amino Acid Sequence, Bacillus subtilis/*genetics/metabolism, Protoporphyrins/metabolism, Recombinant Fusion Proteins/biosynthesis, Sequence Analysis, DNA, Sequence Deletion, Species Specificity
in
Journal of Bacteriology
volume
176
issue
19
pages
5962 - 5970
publisher
American Society for Microbiology
external identifiers
  • scopus:0027969301
ISSN
0021-9193
language
English
LU publication?
yes
id
2c3cb378-4a7e-45a2-b16b-00878cbec743 (old id 8001505)
alternative location
http://www.ncbi.nlm.nih.gov/pubmed/7928957
date added to LUP
2015-10-01 09:19:00
date last changed
2017-02-19 03:42:33
@article{2c3cb378-4a7e-45a2-b16b-00878cbec743,
  abstract     = {The hemY gene of the Bacillus subtilis hemEHY operon is essential for protoheme IX biosynthesis. Two previously isolated hemY mutations were sequenced. Both mutations are deletions affecting the hemY reading frame, and they cause the accumulation of coproporphyrinogen III or coproporphyrin III in the growth medium and the accumulation of trace amounts of other porphyrinogens or porphyrins intracellularly. HemY was found to be a 53-kDa peripheral membrane-bound protein. In agreement with recent findings by Dailey et al. (J. Biol. Chem. 269:813-815, 1994) B. subtilis HemY protein synthesized in Escherichia coli oxidized coproporphyrinogen III and protoporphyrinogen IX to coproporphyrin and protoporphyrin, respectively. The protein is not a general porphyrinogen oxidase since it did not oxidize uroporphyrinogen III. The apparent specificity constant, kcat/Km, for HemY was found to be about 12-fold higher with coproporphyrinogen III as a substrate compared with protoporphyrinogen IX as a substrate. The protoporphyrinogen IX oxidase activity is consistent with the function of HemY in a late step of protoheme IX biosynthesis, i.e., HemY catalyzes the penultimate step of the pathway. However, the efficient coproporphyrinogen III to coproporphyrin oxidase activity is unexplained in the current view of protoheme IX biosynthesis.},
  author       = {Hansson, Mats and Hederstedt, Lars},
  issn         = {0021-9193},
  keyword      = {Porphyrinogens/*metabolism,Oxidation-Reduction,Mutation,Molecular Sequence Data,Membrane Proteins/biosynthesis/*genetics,Kinetics,Heme/*biosynthesis,Coproporphyrinogens/metabolism,Molecular,Cloning,Base Sequence,Amino Acid Sequence,Bacillus subtilis/*genetics/metabolism,Protoporphyrins/metabolism,Recombinant Fusion Proteins/biosynthesis,Sequence Analysis,DNA,Sequence Deletion,Species Specificity},
  language     = {eng},
  number       = {19},
  pages        = {5962--5970},
  publisher    = {American Society for Microbiology},
  series       = {Journal of Bacteriology},
  title        = {Bacillus subtilis HemY is a peripheral membrane protein essential for protoheme IX synthesis which can oxidize coproporphyrinogen III and protoporphyrinogen IX},
  volume       = {176},
  year         = {1994},
}