A Caltech Library Service

The combining power of myoglobin for alkyl isocyanides and the structure of the myoglobin molecule

Lein, Allen and Pauling, Linus (1956) The combining power of myoglobin for alkyl isocyanides and the structure of the myoglobin molecule. Proceedings of the National Academy of Sciences of the United States of America, 42 (2). pp. 51-54. ISSN 0027-8424.

See Usage Policy.


Use this Persistent URL to link to this item:


It was found by St. George and Pauling(1) that, although the combining powers of ferroheme with ethyl isocyanide, isopropyl isocyanide, and tertiary butyl isocyanide are essentially the same (the extreme values of the equilibrium constants differing by only a factor of 3), hemoglobin combines far more strongly with ethyl isocyanide than with t-butyl isocyanide, corresponding to a factor of 200 in the equilibrium constants, with isopropyl isocyanide having an intermediate value. These facts led St. George and Pauling to the conclusion that there is steric hindrance between the alkyl groups of the isocyanides and a part of the globin in the hemoglobin molecule. Inasmuch as it is known that the heme group is attached to globin by way of an imidazole ring of a histidine side chain of the globin on the side opposite that to which the alkyl isocyanide molecule is attached, it was concluded that the heme groups of hemoglobin are buried within the protein molecule.

Item Type:Article
Related URLs:
URLURL TypeDescription
Additional Information:© 1956 by the National Academy of Sciences. Communicated November 26, 1955. Gates and Crellin Laboratories of Chemistry, Contribution No. 2059.
Issue or Number:2
Record Number:CaltechAUTHORS:LEIpnas56
Persistent URL:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:9216
Deposited By: Tony Diaz
Deposited On:27 Nov 2007
Last Modified:02 Oct 2019 23:58

Repository Staff Only: item control page