dc.contributor.author | Pinakoulaki, Eftychia | en |
dc.contributor.author | Koutsoupakis, Constantinos | en |
dc.contributor.author | Sawai, H. | en |
dc.contributor.author | Pavlou, A. | en |
dc.contributor.author | Kato, Y. | en |
dc.contributor.author | Asano, Y. | en |
dc.contributor.author | Aono, S. | en |
dc.creator | Pinakoulaki, Eftychia | en |
dc.creator | Koutsoupakis, Constantinos | en |
dc.creator | Sawai, H. | en |
dc.creator | Pavlou, A. | en |
dc.creator | Kato, Y. | en |
dc.creator | Asano, Y. | en |
dc.creator | Aono, S. | en |
dc.date.accessioned | 2019-11-21T06:22:19Z | |
dc.date.available | 2019-11-21T06:22:19Z | |
dc.date.issued | 2011 | |
dc.identifier.issn | 1520-6106 | |
dc.identifier.uri | http://gnosis.library.ucy.ac.cy/handle/7/56027 | |
dc.description.abstract | Fourier transform infrared (FTIR) spectra, "light" minus "dark" difference FTIR spectra, and time-resolved step-scan (TRS 2) FTIR spectra are reported for carbonmonoxy aldoxime dehydratase. Two C-O modes of heme at 1945 and 1964 cm-1 have been identified and remained unchanged in H2O/D2O exchange and in the pH 5.6-8.5 range, suggesting the presence of two conformations at the active site. The observed C-O frequencies are 5 and 16 cm-1 lower and higher, respectively, than that obtained previously (Oinuma, K.-I. | en |
dc.description.abstract | et al. FEBS Lett.2004, 568, 44-48). We suggest that the strength of the Fe-His bond and the neutralization of the negatively charged propionate groups modulate the ν(Fe-CO)/ν(CO) back-bonding correlation. The "light" minus "dark" difference FTIR spectra indicate that the heme propionates are in both the protonated and deprotonated forms, and the photolyzed CO becomes trapped within a ligand docking site (ν(CO) = 2138 cm-1). The TRS2-FTIR spectra show that the rate of recombination of CO to the heme is k1945 cm-1 = 126 ± 20 s -1 and k1964 cm-1 = 122 ± 20 s -1 at pH 5.6, and k1945 cm-1 = 148 ± 30 s-1 and k1964 cm-1 = 158 ± 32 s -1 at pH 8.5. The rate of decay of the heme propionate vibrations is on a time scale coincident with the rate of rebinding, suggesting that there is a coupling between ligation dynamics in the distal heme environment and the environment sensed by the heme propionates. The implications of these results with respect to the proximal His-Fe heme environment including the propionates and the positively charged or proton-donating residues in the distal pocket which are crucial for the synthesis of nitriles are discussed. © 2011 American Chemical Society. | en |
dc.source | Journal of Physical Chemistry B | en |
dc.source.uri | https://www.scopus.com/inward/record.uri?eid=2-s2.0-80455129765&doi=10.1021%2fjp205944e&partnerID=40&md5=6a74e830eb2b986a6758d0487d641eed | |
dc.subject | Time-scales | en |
dc.subject | Vibrations (mechanical) | en |
dc.subject | Volatile fatty acids | en |
dc.subject | Time-resolved | en |
dc.subject | Cyanides | en |
dc.subject | FT-IR spectrum | en |
dc.subject | Fourier transforms | en |
dc.subject | Protonated | en |
dc.subject | Active site | en |
dc.subject | Fourier transform infrared | en |
dc.subject | Porphyrins | en |
dc.subject | Aldoxime dehydratase | en |
dc.subject | Back-bonding | en |
dc.subject | Deprotonated form | en |
dc.subject | Distal pocket | en |
dc.subject | Heme propionates | en |
dc.subject | Ligand docking | en |
dc.subject | Positively charged | en |
dc.subject | Rate of recombination | en |
dc.subject | Triple bonds | en |
dc.title | Aldoxime dehydratase: Probing the heme environment involved in the synthesis of the carbon-nitrogen triple bond | en |
dc.type | info:eu-repo/semantics/article | |
dc.identifier.doi | 10.1021/jp205944e | |
dc.description.volume | 115 | |
dc.description.issue | 44 | |
dc.description.startingpage | 13012 | |
dc.description.endingpage | 13018 | |
dc.author.faculty | 002 Σχολή Θετικών και Εφαρμοσμένων Επιστημών / Faculty of Pure and Applied Sciences | |
dc.author.department | Τμήμα Χημείας / Department of Chemistry | |
dc.type.uhtype | Article | en |
dc.description.notes | <p>Cited By :7</p> | en |
dc.source.abbreviation | J Phys Chem B | en |
dc.contributor.orcid | Pinakoulaki, Eftychia [0000-0003-3320-6112] | |
dc.gnosis.orcid | 0000-0003-3320-6112 | |