Abstract:
:The distal side of the heme pocket, known to regulate ligand affinity, is shown to be directly involved in subunit interactions. Valency hybrids with oxygen or carbon monoxide bound to the reduced chain are used to model R-state hemoglobin with different distal perturbations. Electron paramagnetic resonance of the oxidized chains shows that the carbon monoxide perturbation is transmitted between subunits to the distal histidine and the oxidized iron center. A comparison of hybrids with only one type of chain oxidized and hybrids with a single alpha beta dimer oxidized is consistent with this perturbation being transmitted across the alpha 1 beta 1 interface. This represents a new mode of subunit interactions in hemoglobin.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Levy A,Sharma VS,Zhang L,Rifkind JMdoi
10.1016/S0006-3495(92)81879-9subject
Has Abstractpub_date
1992-03-01 00:00:00pages
750-5issue
3eissn
0006-3495issn
1542-0086pii
S0006-3495(92)81879-9journal_volume
61pub_type
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