uu.seUppsala University Publications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Probing the Role of the Heme Distal and Proximal Environment in Ligand Dynamics in the Signal Transducer Protein HemAT by Time-Resolved Step-Scan FTIR and Resonance Raman Spectroscopy
Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Molecular Biomimetics. Univ Cyprus, Dept Chem, POB 20537, CY-1678 Nicosia, Cyprus.
Univ Cyprus, Dept Chem, POB 20537, CY-1678 Nicosia, Cyprus..
Natl Inst Nat Sci, Okazaki Inst Integrat Biosci, Inst Mol Sci, 5-1 Higashiyama, Okazaki, Aichi 4448787, Japan.;Univ Tokyo, Dept Chem, Tokyo, Japan..
Natl Inst Nat Sci, Okazaki Inst Integrat Biosci, Inst Mol Sci, 5-1 Higashiyama, Okazaki, Aichi 4448787, Japan..
Show others and affiliations
2017 (English)In: Biochemistry, ISSN 0006-2960, E-ISSN 1520-4995, Vol. 56, no 40, p. 5309-5317Article in journal (Refereed) Published
Abstract [en]

HemAT is a heme-containing oxygen sensor protein that controls aerotaxis. Time-resolved step-scan FTIR studies were performed on the isolated sensor domain and full-length HemAT proteins as well as on the Y70F (B-helix), L92A (E-helix), T95A (E-helix), and Y133F (G-helix) mutants to elucidate the effect of the site-specific mutations on the ligand dynamics subsequent to CO photolysis. The mutations aimed to perturb H-bonding and electrostatic interactions near the heme Fe-bound gaseous ligand (CO) and the heme proximal environment. Rebinding of CO to the heme Fe is biphasic in the sensor domain and full-length HemAT, as well as in the mutants, with the exception of the Y133F mutant protein. The monophasic rebinding of CO in Y133F suggests that in the absence of the H-bond between Y133 and the heme proximal H123 residue the ligand rebinding process is significantly affected. The role of the proximal environment is also probed by resonance Raman photodissociation experiments, in which the Fe His mode of the photoproduct of sensor domain HemAT-CO is detected at a frequency higher than that of the deoxy form in the difference resonance Raman spectra. The role of the conformational changes of Y133 (G-helix) and the role of the distal L92 and T95 residues (E-helix) in regulating ligand dynamics in the heme pocket are discussed.

Place, publisher, year, edition, pages
AMER CHEMICAL SOC , 2017. Vol. 56, no 40, p. 5309-5317
National Category
Chemical Sciences
Identifiers
URN: urn:nbn:se:uu:diva-340144DOI: 10.1021/acs.biochem.7b00558ISI: 000412966200013PubMedID: 28876054OAI: oai:DiVA.org:uu-340144DiVA, id: diva2:1177978
Available from: 2018-01-26 Created: 2018-01-26 Last updated: 2018-01-26Bibliographically approved

Open Access in DiVA

No full text in DiVA

Other links

Publisher's full textPubMed

Authority records BETA

Pavlou, Andrea

Search in DiVA

By author/editor
Pavlou, Andrea
By organisation
Molecular Biomimetics
In the same journal
Biochemistry
Chemical Sciences

Search outside of DiVA

GoogleGoogle Scholar

doi
pubmed
urn-nbn

Altmetric score

doi
pubmed
urn-nbn
Total: 25 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf