Laser desorption supersonic jet spectroscopy of hydrated tyrosine

June 18th, 2013

Hikari OBA

Tokyo Tech, Japan

Cooperative effect of hydrogen bond

*R. Nathaniel Pribble, et al.J. Chem. Phys., 106, 2145 (1997).

Bz-(MeOH)1

Bz-(MeOH)2

Why tyrosine-water cluster ?

Phenylalanine X

Tyrosine XR

Dopa

different ! almost same

[1]　 L. C. Snoek, et al., CPL, 2000 321 49. [2] Y. Shimozono, et al., PCCP, 2013, 15, 5163. [3] S. Ishiuchi, et al., PCCP, 2011, 13, 7812

Why tyrosine-water cluster ?

Stronger H-bond

To Investigate cooperative effect of separate hydrogen bond

more enhanced ?

Dopa

weaker H-bond

Tyr XR-(H2O)1

Laser desorption supersonic jet

REMPI and IR dip spectroscopyREMPI IR dip

REMPI spectra

bands 1bands 2

[1] Y. Shimozono, et al., PCCP, 2013, 15, 5163

[1]

REMPI

A)

B)

Different structures!

IR dip spectra of Tyr-(H2O)1 cluster

Assignment of water binding site

free OHH-bonded OH

*　 T. Ebata, et al., International Journal of Mass Spectrometry and Ion Processes, 1996, 159, 111.

*

A)

B)

Tyr-(H2O)1

Phenol

Phenol-(H2O)1

*

Assignment of water binding site

bands 1bands 2 (phenolic OH bound)

Assignment of conformation of tyrosine-(H2O)1

Tyr XR-(H2O)1

Tyr XR

Tyr XR-(H2O)1

[1]

[1] Y. Shimozono, et al., PCCP, 2013, 15, 5163

phenolic OH bound

Phe X

Tyr XR

Dopa

Tyr XR-(H2O)1

Comparison of the effect on hydrogen bond in amino acid

stronger H-bond

weaker H-bond

This work !

?

Importance of direction of dipole moments

Dopa

Tyr XR-(H2O)1

Different direction !

Summary

REMPI and IR dip spectra of tyrosine-(H2O)1 were measured.

Direction of dipole moments is important to enhance the hydrogen bond strength in cooperative effect.

Acknowledgment

Merci beaucoup !

Ms. Yoko Shimozono

Dr. Shun-ichi Ishiuchi

Prof. Masaaki Fujii Chemical Resources Lab., Tokyo Tech.

Chemical Resources Lab., Tokyo Tech.

Chemical Resources Lab., Tokyo Tech.

Dr. Pierre Çarçabal Institut des Sciences Moléculaires d’Orsay, U. Paris-Sud.

IR-UV Hole Burning spectra

Dipole moment of amino acid site and OH site

REMPI spectra of Tyr, Tyr-(H2O)1, Dopa

Assignment of conformation

A)

B)

Amino acid bound Phenolic OH bound

IR spectra of 12 conformers of tyrosine [1]

Assignment of amino acid chain

[1] Y. Shimozono, et al., PCCP, 2013.