| Structural highlights
Function
[AAUA_ALCFA] Oxidizes primary aromatic amines and, more slowly, some long-chain aliphatic amines, but not methylamine or ethylamine. Uses azurin as an electron acceptor to transfer electrons from the reduced tryptophylquinone cofactor.[1] [2] [3] [4] [5] [6] [7] [AAUB_ALCFA] Oxidizes primary aromatic amines and, more slowly, some long-chain aliphatic amines, but not methylamine or ethylamine. Uses azurin as an electron acceptor to transfer electrons from the reduced tryptophylquinone cofactor.[8] [9] [10] [11]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Structure-activity correlations have been employed previously in the mechanistic interpretation of TTQ-dependent amine dehydrogenases using a series of para-substituted benzylamines. However, by combining the use of kinetic isotope effects (KIEs) and crystallographic analysis, in conjunction with structure-reactivity correlation studies, we show that para-substituted benzylamines are poor reactivity probes for TTQ-dependent aromatic amine dehydrogenase (AADH). Stopped-flow kinetic studies of the reductive half-reaction, with para-substituted benzylamines and their dideuterated counterparts, demonstrate that C-H or C-D bond breakage is not fully rate limiting (KIEs approximately unity). Contrary to previous reports, Hammett plots exhibit a poor correlation of structure-reactivity data with electronic substituent effects for para-substituted benzylamines and phenylethylamines. Crystallographic studies of enzyme-substrate complexes reveal that the observed structure-reactivity correlations are not attributed to distinct binding modes for para-substituted benzylamines in the active site, although two binding sites for p-nitrobenzylamine are identified. We identify structural rearrangements, prior to the H-transfer step, which are likely to limit the rate of TTQ reduction by benzylamines. This work emphasizes (i) the need for caution when applying structure-activity correlations to enzyme-catalyzed reactions and (ii) the added benefit of using both isotope effects and structural analysis, in conjunction with structure-reactivity relationships, to study chemical steps in enzyme reaction cycles.
Isotope effects reveal that para-substituted benzylamines are poor reactivity probes of the quinoprotein mechanism for aromatic amine dehydrogenase.,Hothi P, Roujeinikova A, Khadra KA, Lee M, Cullis P, Leys D, Scrutton NS Biochemistry. 2007 Aug 14;46(32):9250-9. Epub 2007 Jul 18. PMID:17636875[12]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Chistoserdov AY. Cloning, sequencing and mutagenesis of the genes for aromatic amine dehydrogenase from Alcaligenes faecalis and evolution of amine dehydrogenases. Microbiology. 2001 Aug;147(Pt 8):2195-202. PMID:11495996
- ↑ Hothi P, Khadra KA, Combe JP, Leys D, Scrutton NS. Tryptophan tryptophylquinone cofactor biogenesis in the aromatic amine dehydrogenase of Alcaligenes faecalis. Cofactor assembly and catalytic properties of recombinant enzyme expressed in Paracoccus denitrificans. FEBS J. 2005 Nov;272(22):5894-909. PMID:16279953 doi:http://dx.doi.org/EJB4990
- ↑ Govindaraj S, Eisenstein E, Jones LH, Sanders-Loehr J, Chistoserdov AY, Davidson VL, Edwards SL. Aromatic amine dehydrogenase, a second tryptophan tryptophylquinone enzyme. J Bacteriol. 1994 May;176(10):2922-9. PMID:8188594
- ↑ Edwards SL, Davidson VL, Hyun YL, Wingfield PT. Spectroscopic evidence for a common electron transfer pathway for two tryptophan tryptophylquinone enzymes. J Biol Chem. 1995 Mar 3;270(9):4293-8. PMID:7876189
- ↑ Sukumar N, Chen ZW, Ferrari D, Merli A, Rossi GL, Bellamy HD, Chistoserdov A, Davidson VL, Mathews FS. Crystal structure of an electron transfer complex between aromatic amine dehydrogenase and azurin from Alcaligenes faecalis. Biochemistry. 2006 Nov 14;45(45):13500-10. PMID:17087503 doi:http://dx.doi.org/10.1021/bi0612972
- ↑ Roujeinikova A, Scrutton NS, Leys D. Atomic level insight into the oxidative half-reaction of aromatic amine dehydrogenase. J Biol Chem. 2006 Dec 29;281(52):40264-72. Epub 2006 Sep 27. PMID:17005560 doi:http://dx.doi.org/10.1074/jbc.M605559200
- ↑ Masgrau L, Roujeinikova A, Johannissen LO, Hothi P, Basran J, Ranaghan KE, Mulholland AJ, Sutcliffe MJ, Scrutton NS, Leys D. Atomic description of an enzyme reaction dominated by proton tunneling. Science. 2006 Apr 14;312(5771):237-41. PMID:16614214 doi:312/5771/237
- ↑ Chistoserdov AY. Cloning, sequencing and mutagenesis of the genes for aromatic amine dehydrogenase from Alcaligenes faecalis and evolution of amine dehydrogenases. Microbiology. 2001 Aug;147(Pt 8):2195-202. PMID:11495996
- ↑ Hothi P, Khadra KA, Combe JP, Leys D, Scrutton NS. Tryptophan tryptophylquinone cofactor biogenesis in the aromatic amine dehydrogenase of Alcaligenes faecalis. Cofactor assembly and catalytic properties of recombinant enzyme expressed in Paracoccus denitrificans. FEBS J. 2005 Nov;272(22):5894-909. PMID:16279953 doi:http://dx.doi.org/EJB4990
- ↑ Govindaraj S, Eisenstein E, Jones LH, Sanders-Loehr J, Chistoserdov AY, Davidson VL, Edwards SL. Aromatic amine dehydrogenase, a second tryptophan tryptophylquinone enzyme. J Bacteriol. 1994 May;176(10):2922-9. PMID:8188594
- ↑ Masgrau L, Roujeinikova A, Johannissen LO, Hothi P, Basran J, Ranaghan KE, Mulholland AJ, Sutcliffe MJ, Scrutton NS, Leys D. Atomic description of an enzyme reaction dominated by proton tunneling. Science. 2006 Apr 14;312(5771):237-41. PMID:16614214 doi:312/5771/237
- ↑ Hothi P, Roujeinikova A, Khadra KA, Lee M, Cullis P, Leys D, Scrutton NS. Isotope effects reveal that para-substituted benzylamines are poor reactivity probes of the quinoprotein mechanism for aromatic amine dehydrogenase. Biochemistry. 2007 Aug 14;46(32):9250-9. Epub 2007 Jul 18. PMID:17636875 doi:10.1021/bi7007239
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