Abstract:
:A significant amount of work has been devoted to obtaining a detailed atomistic knowledge of the human hemoglobin mechanism. Despite this impressive research, to date, the ligand diffusion processes remain unclear and controversial. Using recently developed computational techniques, PELE, we are capable of addressing the ligand migration processes. First, the methodology was tested on myoglobin's CO migration, and the results were compared with the wealth of theoretical and experimental studies. Then, we explored both hemoglobin tense and relaxed states and identified the differences between the α-and β-subunits. Our results indicate that the proximal site, equivalent to the Xe1 cavity in myoglobin, is never visited. Furthermore, strategically positioned residues alter the diffusion processes within hemoglobin's subunits and suggest that multiple pathways exist, especially diversified in the α-globins. A significant dependency of the ligand dynamics on the tertiary structure is also observed.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Lucas MF,Guallar Vdoi
10.1016/j.bpj.2012.01.011subject
Has Abstractpub_date
2012-02-22 00:00:00pages
887-96issue
4eissn
0006-3495issn
1542-0086pii
S0006-3495(12)00084-7journal_volume
102pub_type
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