The role of short-chain conjugated poly-(R)-3-hydroxybutyrate (cPHB) in protein folding

Int J Mol Sci. 2013 May 23;14(6):10727-48. doi: 10.3390/ijms140610727.


Poly-(R)-3-hydroxybutyrate (PHB), a linear polymer of R-3-hydroxybutyrate (R-3HB), is a fundamental constituent of biological cells. Certain prokaryotes accumulate PHB of very high molecular weight (10,000 to >1,000,000 residues), which is segregated within granular deposits in the cytoplasm; however, all prokaryotes and all eukaryotes synthesize PHB of medium-chain length (~100-200 residues) which resides within lipid bilayers or lipid vesicles, and PHB of short-chain length (<12 residues) which is conjugated to proteins (cPHB), primarily proteins in membranes and organelles. The physical properties of cPHB indicate it plays important roles in the targeting and folding of cPHB-proteins. Here we review the occurrence, physical properties and molecular characteristics of cPHB, and discuss its influence on the folding and structure of outer membrane protein A (OmpA) of Escherichia coli.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Bacterial Outer Membrane Proteins / chemistry
  • Bacterial Outer Membrane Proteins / metabolism
  • Escherichia coli / metabolism
  • Hydroxybutyrates / chemistry
  • Hydroxybutyrates / metabolism*
  • Polyesters / chemistry
  • Polyesters / metabolism*
  • Protein Folding*


  • Bacterial Outer Membrane Proteins
  • Hydroxybutyrates
  • Polyesters
  • OMPA outer membrane proteins
  • poly-beta-hydroxybutyrate