HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Yamamoto, H. Articles by Yonetani, T. Search for Related Content PubMed PubMed Citation Articles by Yamamoto, H. Articles by Yonetani, T. Social Bookmarking                      What's this?

Studies on Modified Hemoglobins

IV. HYBRID HEMOGLOBINS CONTAINING PROTO- AND MESOHEMES AND THEIR OXYGENATION CHARACTERISTICS

From the ¹ From the Johnson Research Foundation, Department of Biophysics and Physical Biochemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19174

An artificial hybrid hemoglobin, (Meso)ß(Proto), the and ß subunits of which contain meso- and protohemes, respectively, and its complementary hybrid, (Proto)ß(Meso), were prepared. These hybrid hemoglobins are indistinguishable from native protohemoglobin and artificial mesohemoglobin in terms of electrophoretic and molecular sieving characteristics. The visible absorption spectra of the hybrid hemoglobins show minor differences between them as well as from those of an equimolar mixture of proto- and mesohemoglobins.

The Hill plot of the absorbance changes upon oxygenation of (Proto)ß(Meso) are independent of measuring wavelengths and give identical oxygenation parameters for the protoheme-containing subunits and the mesoheme-containing ß subunits. On the other hand, the Hill plot of the absorbance changes upon oxygenation of (Meso)ß(Proto) is dependent on measuring wavelengths as that of an equimolar mixture of proto- and mesohemoglobins. A method has been devised to calculate individual oxygenation parameters for the mesoheme-containing subunits and the protoheme-containing ß subunits in (Meso)ß(Proto). The comparison of the oxygenation parameters of the hybrids with those of proto- and mesohemoglobins suggests that the intricate intersubunit contacts which exist in the highly cooperative protohemoglobin may have been perturbed by the partial and complete substitutions of the prosthetic groups with mesoheme for protoheme.

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?