Pii: S0025-5564(99)00050-4
نویسندگان
چکیده
The paper discusses combinatorial and probabilistic models allowing to characterize various aspects of spacial symmetry and structural heterogeneity of the giant hexagonal bilayer hemoglobins (HBL Hb). Linker±dodecamer con®gurations of HBL are described for two and four linker types (occurring in the two most studied HBL Hb of Arenicola and Lumbricus, respectively), and the most probable con®gurations are found. It is shown that, for HBL with marked dodecamers, the number of `normal-marked' pairs of dodecamers in homological position follows a binomial distribution. The group of symmetries of the dodecamer substructure of HBL is identi®ed with the dihedral group D6. Under natural symmetry assumptions, the total dipole moment of the dodecamer substructure of HBL is shown to be zero. Biological implications of the mathematical ®ndings are discussed. Ó 2000 Elsevier Science Inc. All rights reserved.
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