Multiple conformations of PEVK proteins detected by single-molecule techniques.


Journal Article

An important component of muscle elasticity is the PEVK region of titin, so named because of the preponderance of these amino acids. However, the PEVK region, similar to other elastomeric proteins, is thought to form a random coil and therefore its structure cannot be determined by standard techniques. Here we combine single-molecule electron microscopy and atomic force microscopy to examine the conformations of the human cardiac titin PEVK region. In contrast to a simple random coil, we have found that cardiac PEVK shows a wide range of elastic conformations with end-to-end distances ranging from 9 to 24 nm and persistence lengths from 0.4 to 2.5 nm. Individual PEVK molecules retained their distinctive elastic conformations through many stretch-relaxation cycles, consistent with the view that these PEVK conformers cannot be interconverted by force. The multiple elastic conformations of cardiac PEVK may result from varying degrees of proline isomerization. The single-molecule techniques demonstrated here may help elucidate the conformation of other proteins that lack a well-defined structure.

Full Text

Duke Authors

Cited Authors

  • Li, H; Oberhauser, AF; Redick, SD; Carrion-Vazquez, M; Erickson, HP; Fernandez, JM

Published Date

  • September 11, 2001

Published In

Volume / Issue

  • 98 / 19

Start / End Page

  • 10682 - 10686

PubMed ID

  • 11526214

Pubmed Central ID

  • 11526214

International Standard Serial Number (ISSN)

  • 0027-8424

Digital Object Identifier (DOI)

  • 10.1073/pnas.191189098


  • eng

Conference Location

  • United States