Premium
An estimation of the dimensions of the phycocyanin molecule
Author(s) -
Jennings B. R.
Publication year - 1968
Publication title -
biopolymers
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.556
H-Index - 125
eISSN - 1097-0282
pISSN - 0006-3525
DOI - 10.1002/bip.1968.360060812
Subject(s) - random hexamer , monomer , chemistry , globular protein , aggregate (composite) , macromolecule , ellipsoid , crystallography , chemical physics , nanotechnology , polymer , organic chemistry , materials science , physics , biochemistry , astronomy
Knowledge of the total particle volume and the specific volumes of the constituent polar and nonpolar amino acid residues of a globular protein may be used in suitable instances to estimate the size and shape, of the macromolecule. Use has been made of the data, which is available in the literature for phycocyanin from Plectonema calothricoidcs , to predict possible models for the monomer and hexamer forms of this protein. The monomer is well represented by a prolate ellipsoid with semiaxes of 45 and 17Å and an approximate molecular weight of (46000). The hexamer is envisaged as the aggregate of six such monomers, in juxtaposition, with their major axes parallel so as to form a closed ring structure of about 268000 molecular weight. These proposed models are consistent with the previously published electron micrographs and hydrodynamic properties of this protein.