Reactions of excited triplet states of metal-substituted myoglobins

Sandor J. Papp; Jane M. Vanderkooi; Charles M. Phillips

doi:10.1117/12.17734

1 May 1990 Reactions of excited triplet states of metal-substituted myoglobins

Sandor J. Papp, Jane M. Vanderkooi, Charles M. Phillips

Proceedings Volume 1204, Time-Resolved Laser Spectroscopy in Biochemistry II; (1990) https://doi.org/10.1117/12.17734
Event: OE/LASE '90, 1990, Los Angeles, CA, United States

Abstract

The small-molecule (i.e. oxygen) penetrability into proteins carries important implications for both the structural character and dynamic properties of proteins. We investigated aspects of protein dynamics by studying triplet-state quenching of Zn and Pd derivatives of myoglobin by oxygen. These two derivatives make an interesting comparison because the Zn derivative of myoglobin is five coordinated and is out-of-plane (as is deoxy myoglobin), whereas Pd porphyrin is planar (as is oxy myoglobin). Therefore relaxation of the polypeptide chain in the excited state analogues of the two functional conformations of myoglobin can be studied. In case of Znmyoglobin, the spectra did not exhibit an isosbestic point and the decay kinetics to the ground state dependtd upon the wavelength of measurement. The decay profiles could be fit by a double exponential function with a good correlation. In the case of Pd-myoglobin an isosbestic point was observed in the emission and the decay profile could be fit with a single exponential function. The comparison of the quenching constants for the two metal substituted derivatives suggests that there is no significant difference between the oxygen penetrability of the Zn and the Pd substituted myoglobins.

Citation Download Citation

Sandor J. Papp, Jane M. Vanderkooi, and Charles M. Phillips "Reactions of excited triplet states of metal-substituted myoglobins", Proc. SPIE 1204, Time-Resolved Laser Spectroscopy in Biochemistry II, (1 May 1990); https://doi.org/10.1117/12.17734

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available