Crystallization (Comment) | Organism |
---|---|
heme oxygenase HmuO in tertiary complex with reaction intermediate verdoheme and N3, X-ray diffraction structure determination and analysis at 1.7 resolution | Corynebacterium diphtheriae |
heme oxygenase HO1 complexed with reaction intermediate verdoheme, and in tertiary complex with verdoheme and NO, X-ray diffraction structure determination and analysis at 2.2 and 2.1 A resolution, respectively | Homo sapiens |
heme oxygenase HO1 complexed with reaction intermediate verdoheme, X-ray diffraction structure determination and analysis at 2.2 A resolution | Rattus norvegicus |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
CO | the third reaction step is inhibited by CO | Corynebacterium diphtheriae | |
CO | the third reaction step is inhibited by CO | Homo sapiens | |
CO | the third reaction step is inhibited by CO | Rattus norvegicus |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
heme + 3 AH2 + 3 O2 | Homo sapiens | - |
biliverdin + Fe2+ + CO + 3 A + 3 H2O | - |
? | |
heme + 3 AH2 + 3 O2 | Rattus norvegicus | - |
biliverdin + Fe2+ + CO + 3 A + 3 H2O | - |
? | |
heme + 3 AH2 + 3 O2 | Corynebacterium diphtheriae | - |
biliverdin + Fe2+ + CO + 3 A + 3 H2O | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Corynebacterium diphtheriae | Q54AI1 | - |
- |
Homo sapiens | P09601 | - |
- |
Rattus norvegicus | P06762 | - |
- |
Reaction | Comment | Organism | Reaction ID |
---|---|---|---|
protoheme + 3 [reduced NADPH-hemoprotein reductase] + 3 O2 = biliverdin + Fe2+ + CO + 3 [oxidized NADPH-hemoprotein reductase] + 3 H2O | heme degradation by heme oxygenase proceeds through three successive steps of O2 activation. The first step is formation of alpha-meso-hydroxyheme from heme, second formation of verdoheme from alpha-meso-hydroxyheme, the third step is the ring opening of verdoheme. Only alpha-verdoheme with the O atom in its alpha position, and not beta-, gamma-, or delta-verdoheme, is converted to biliverdin. The third step, like the first, shows regiospecificity, the distal Asp plays an important role in this step, similar to the first. The substrate heme is sandwiched between two helices, termed the proximal and distal helices. Reaction mechanism, overview | Homo sapiens | |
protoheme + 3 [reduced NADPH-hemoprotein reductase] + 3 O2 = biliverdin + Fe2+ + CO + 3 [oxidized NADPH-hemoprotein reductase] + 3 H2O | heme degradation by heme oxygenase proceeds through three successive steps of O2 activation. The first step is formation of alpha-meso-hydroxyheme from heme, second formation of verdoheme from alpha-meso-hydroxyheme, the third step is the ring opening of verdoheme. Only alpha-verdoheme with the O atom in its alpha position, and not beta-, gamma-, or delta-verdoheme, is converted to biliverdin. The third step, like the first, shows regiospecificity, the distal Asp plays an important role in this step, similar to the first. The substrate heme is sandwiched between two helices, termed the proximal and distal helices. Reaction mechanism, overview | Rattus norvegicus | |
protoheme + 3 [reduced NADPH-hemoprotein reductase] + 3 O2 = biliverdin + Fe2+ + CO + 3 [oxidized NADPH-hemoprotein reductase] + 3 H2O | heme degradation by heme oxygenase proceeds through three successive steps of O2 activation. The first step is formation of alpha-meso-hydroxyheme from heme, second formation of verdoheme from alpha-meso-hydroxyheme, the third step is the ring opening of verdoheme. Only alpha-verdoheme with the O atom in its alpha position, and not beta-, gamma-, or delta-verdoheme, is converted to biliverdin. The third step, like the first, shows regiospecificity, the distal Asp plays an important role in this step, similar to the first. The substrate heme is sandwiched between two helices, termed the proximal and distal helices. Reaction mechanism, overview | Corynebacterium diphtheriae |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
heme + 3 AH2 + 3 O2 | - |
Homo sapiens | biliverdin + Fe2+ + CO + 3 A + 3 H2O | - |
? | |
heme + 3 AH2 + 3 O2 | - |
Rattus norvegicus | biliverdin + Fe2+ + CO + 3 A + 3 H2O | - |
? | |
heme + 3 AH2 + 3 O2 | - |
Corynebacterium diphtheriae | biliverdin + Fe2+ + CO + 3 A + 3 H2O | - |
? | |
heme + 3 AH2 + 3 O2 | reaction intermediate verdoheme and the verdoheme-enzyme complex are gradually degraded in the presence of O2 | Homo sapiens | biliverdin + Fe2+ + CO + 3 A + 3 H2O | - |
? | |
heme + 3 AH2 + 3 O2 | reaction intermediate verdoheme and the verdoheme-enzyme complex are gradually degraded in the presence of O2 | Rattus norvegicus | biliverdin + Fe2+ + CO + 3 A + 3 H2O | - |
? | |
heme + 3 AH2 + 3 O2 | reaction intermediate verdoheme and the verdoheme-enzyme complex are gradually degraded in the presence of O2 | Corynebacterium diphtheriae | biliverdin + Fe2+ + CO + 3 A + 3 H2O | - |
? |
Subunits | Comment | Organism |
---|---|---|
More | structure comparisons, overview | Homo sapiens |
More | structure comparisons, overview | Rattus norvegicus |
More | structure comparisons, overview | Corynebacterium diphtheriae |
Synonyms | Comment | Organism |
---|---|---|
HmuO | - |
Corynebacterium diphtheriae |
Ho1 | - |
Homo sapiens |
Ho1 | - |
Rattus norvegicus |
General Information | Comment | Organism |
---|---|---|
evolution | bacterial HmuO and mammalian heme oxygenases are similar in their reaction mechanisms and structures | Homo sapiens |
evolution | bacterial HmuO and mammalian heme oxygenases are similar in their reaction mechanisms and structures | Rattus norvegicus |
evolution | HmuO and mammalian heme oxygenases are similar in their reaction mechanisms and structures | Corynebacterium diphtheriae |
malfunction | mutation of the distal Asp decreases the verdoheme ring opening activity | Homo sapiens |
malfunction | mutation of the distal Asp decreases the verdoheme ring opening activity | Rattus norvegicus |
malfunction | mutation of the distal Asp decreases the verdoheme ring opening activity | Corynebacterium diphtheriae |
additional information | heme oxygenase is an enzyme that catalyzes the regiospecific conversion of heme to biliverdin IXalpha, carbon monoxide, and free Fe(II). Heme degradation by heme oxygenase proceeds through three successive steps of O2 activation. The first step is formation of alpha-meso-hydroxyheme from from heme, second formation of verdoheme from alpha-meso-hydroxyheme, the third step is the ring opening of verdoheme, Only alpha-verdoheme with the O atom in its alpha position, and not beta-, gamma-, or delta-verdoheme, is converted to biliverdin. The third step, like the first, shows regiospecificity, the distal Asp plays an important role in this step, similar to the first. The substrate heme is sandwiched between two helices, termed the proximal and distal helices | Homo sapiens |
additional information | heme oxygenase is an enzyme that catalyzes the regiospecific conversion of heme to biliverdin IXalpha, carbon monoxide, and free Fe(II). Heme degradation by heme oxygenase proceeds through three successive steps of O2 activation. The first step is formation of alpha-meso-hydroxyheme from from heme, second formation of verdoheme from alpha-meso-hydroxyheme, the third step is the ring opening of verdoheme, Only alpha-verdoheme with the O atom in its alpha position, and not beta-, gamma-, or delta-verdoheme, is converted to biliverdin. The third step, like the first, shows regiospecificity, the distal Asp plays an important role in this step, similar to the first. The substrate heme is sandwiched between two helices, termed the proximal and distal helices | Rattus norvegicus |
additional information | heme oxygenase is an enzyme that catalyzes the regiospecific conversion of heme to biliverdin IXalpha, carbon monoxide, and free Fe(II). Heme degradation by heme oxygenase proceeds through three successive steps of O2 activation. The first step is formation of alpha-meso-hydroxyheme from heme, second formation of verdoheme from alpha-meso-hydroxyheme, the third step is the ring opening of verdoheme. Only alpha-verdoheme with the O atom in its alpha position, and not beta-, gamma-, or delta-verdoheme, is converted to biliverdin. The third step, like the first, shows regiospecificity, the distal Asp plays an important role in this step, similar to the first. The substrate heme is sandwiched between two helices, termed the proximal and distal helices | Corynebacterium diphtheriae |