Urease oligomerizes in a linear pattern: Further hydrodynamic evidence from intrinsic viscosity theories and measurement

Measurements of the intrinsic viscosity of the urease “monomer” and of a mixture of oligomers are shown to lead to the conclusion that urease oligomerizes in a linear fashion, when viewed in the light of several available theories of intrinsic viscosity of rigid protein macromolecules. This conclusion is also consistent with previously reported work on the sedimentation coefficients of the urease oligomers. The use of a detailed subunit structure for the urease “monomer” and oligomers is explored and found to give quantitatively good results for all hydrodynamic properties of all urease oligomers. The realm of validity of the intrinsic viscosity theories proposed by Garcia de la Torre and Bloomfield, by Tsuda, and by Abdel‐Khalik and Bird is explored in this context.