1n15
From Proteopedia
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==Overview== | ==Overview== | ||
| - | The structures of nitrite reductase from Paracoccus denitrificans GB17, (NiR-Pd) and Pseudomonas aeruginosa (NiR-Pa) have been described for the, oxidized and reduced state (Fulop, V., Moir, J. W. B., Ferguson, S. J., and Hajdu, J. (1995) Cell 81, 369-377; Nurizzo, D., Silvestrini, M. C., Mathieu, M., Cutruzzola, F., Bourgeois, D., Fulop, V., Hajdu, J., Brunori, M., Tegoni, M., and Cambillau, C. (1997) Structure 5, 1157-1171; Nurizzo, D., Cutruzzola, F., Arese, M., Bourgeois, D., Brunori, M., Cambillau, C. , and Tegoni, M. (1998) Biochemistry 37, 13987-13996). Major conformational, rearrangements are observed in the extreme states although they are more, substantial in NiR-Pd. The four structures differ significantly in the c, heme domains. Upon reduction, a His17/Met106 heme-ligand ... | + | The structures of nitrite reductase from Paracoccus denitrificans GB17, (NiR-Pd) and Pseudomonas aeruginosa (NiR-Pa) have been described for the, oxidized and reduced state (Fulop, V., Moir, J. W. B., Ferguson, S. J., and Hajdu, J. (1995) Cell 81, 369-377; Nurizzo, D., Silvestrini, M. C., Mathieu, M., Cutruzzola, F., Bourgeois, D., Fulop, V., Hajdu, J., Brunori, M., Tegoni, M., and Cambillau, C. (1997) Structure 5, 1157-1171; Nurizzo, D., Cutruzzola, F., Arese, M., Bourgeois, D., Brunori, M., Cambillau, C. , and Tegoni, M. (1998) Biochemistry 37, 13987-13996). Major conformational, rearrangements are observed in the extreme states although they are more, substantial in NiR-Pd. The four structures differ significantly in the c, heme domains. Upon reduction, a His17/Met106 heme-ligand switch is, observed in NiR-Pd together with concerted movements of the Tyr in the, distal site of the d1 heme (Tyr10 in NiR-Pa, Tyr25 in NiR-Pd) and of a, loop of the c heme domain (56-62 in NiR-Pa, 99-116 in NiR-Pd). Whether the, reduction of the c heme, which undergoes the major rearrangements, is the, trigger of these movements is the question addressed by our study. This, conformational reorganization is not observed in the partially reduced, species, in which the c heme is partially or largely (15-90%) reduced but, the d1 heme is still oxidized. These results suggest that the d1 heme, reduction is likely to be responsible of the movements. We speculate about, the mechanistic explanation as to why the opening of the d1 heme distal, pocket only occurs upon electron transfer to the d1 heme itself, to allow, binding of the physiological substrate NO2- exclusively to the reduced, metal center. |
==About this Structure== | ==About this Structure== | ||
| - | 1N15 is a | + | 1N15 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Pseudomonas_aeruginosa Pseudomonas aeruginosa] with HEC and DHE as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Transferred_entry:_1.7.2.1 Transferred entry: 1.7.2.1], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.9.3.2 1.9.3.2] Structure known Active Sites: NIA and NIB. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1N15 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: pseudomonas aeruginosa]] | [[Category: pseudomonas aeruginosa]] | ||
| - | ''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Mon Nov 5 14:55:01 2007'' |
Revision as of 12:49, 5 November 2007
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FOLLOWING THE C HEME REDUCTION IN NITRITE REDUCTASE FROM PSEUDOMONAS AERUGINOSA
Overview
The structures of nitrite reductase from Paracoccus denitrificans GB17, (NiR-Pd) and Pseudomonas aeruginosa (NiR-Pa) have been described for the, oxidized and reduced state (Fulop, V., Moir, J. W. B., Ferguson, S. J., and Hajdu, J. (1995) Cell 81, 369-377; Nurizzo, D., Silvestrini, M. C., Mathieu, M., Cutruzzola, F., Bourgeois, D., Fulop, V., Hajdu, J., Brunori, M., Tegoni, M., and Cambillau, C. (1997) Structure 5, 1157-1171; Nurizzo, D., Cutruzzola, F., Arese, M., Bourgeois, D., Brunori, M., Cambillau, C. , and Tegoni, M. (1998) Biochemistry 37, 13987-13996). Major conformational, rearrangements are observed in the extreme states although they are more, substantial in NiR-Pd. The four structures differ significantly in the c, heme domains. Upon reduction, a His17/Met106 heme-ligand switch is, observed in NiR-Pd together with concerted movements of the Tyr in the, distal site of the d1 heme (Tyr10 in NiR-Pa, Tyr25 in NiR-Pd) and of a, loop of the c heme domain (56-62 in NiR-Pa, 99-116 in NiR-Pd). Whether the, reduction of the c heme, which undergoes the major rearrangements, is the, trigger of these movements is the question addressed by our study. This, conformational reorganization is not observed in the partially reduced, species, in which the c heme is partially or largely (15-90%) reduced but, the d1 heme is still oxidized. These results suggest that the d1 heme, reduction is likely to be responsible of the movements. We speculate about, the mechanistic explanation as to why the opening of the d1 heme distal, pocket only occurs upon electron transfer to the d1 heme itself, to allow, binding of the physiological substrate NO2- exclusively to the reduced, metal center.
About this Structure
1N15 is a Single protein structure of sequence from Pseudomonas aeruginosa with HEC and DHE as ligands. Active as Transferred entry: 1.7.2.1, with EC number 1.9.3.2 Structure known Active Sites: NIA and NIB. Full crystallographic information is available from OCA.
Reference
Does the reduction of c heme trigger the conformational change of crystalline nitrite reductase?, Nurizzo D, Cutruzzola F, Arese M, Bourgeois D, Brunori M, Cambillau C, Tegoni M, J Biol Chem. 1999 May 21;274(21):14997-5004. PMID:10329702
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