Abstract:
:The rate constants for CO binding to the five-coordinate ferrous iron complexes of 5,10,15,20-[pyromellitoyl(tetrakis-o-oxyoxyphenyl)]porphyrin and 5,10,15,20-[pyromellitoyl(tetrakis-o-oxypropoxyphenyl)]porphyrin have been measured and compared with the corresponding rate constants for other hemes and hemoproteins. The second-order rate constant is independent of cap size and is comparable to that of high-affinity state hemoglobin (k5 approximately 4 X 10(6) M-1s-1). Therefore, these capped porphyrins provide no steric hindrance to CO binding. In addition, a kinetic scheme involving an unusual seven-coordinate porphyrin species is described.
journal_name
Proc Natl Acad Sci U S Aauthors
Rose EJ,Venkatasubramanian PN,Swartz JC,Jones RD,Basolo F,Hoffman BMdoi
10.1073/pnas.79.18.5742subject
Has Abstractpub_date
1982-09-01 00:00:00pages
5742-5issue
18eissn
0027-8424issn
1091-6490journal_volume
79pub_type
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