A circular dichroism study of the protective role of polyphosphoesters polymer chains in polyphosphoester-myoglobin conjugates

Chirality. 2022 Sep;34(9):1257-1265. doi: 10.1002/chir.23486. Epub 2022 Jun 17.

Abstract

Protein-polymer conjugates are a blooming class of hybrid systems with high biomedical potential. Despite a plethora of papers on their biomedical properties, the physical-chemical characterization of many protein-polymer conjugates is missing. Here, we evaluated the thermal stability of a set of fully-degradable polyphosphoester-protein conjugates by variable temperature circular dichroism, a common but powerful technique. We extensively describe their thermodynamic stability in different environments (in physiological buffer or in presence of chemical denaturants, e.g., acid or urea), highlighting the protective role of the polymer in preserving the protein from denaturation. For the first time, we propose a simple but effective protocol to achieve useful information on these systems in vitro, useful to screen new samples in their early stages.

Keywords: circular dichroism; polyphosphoesters; protein thermal stability; protein unfolding; protein-polymer conjugates.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Circular Dichroism
  • Myoglobin*
  • Polymers* / chemistry
  • Protein Denaturation
  • Stereoisomerism
  • Thermodynamics

Substances

  • Myoglobin
  • Polymers