Improved non-chromatographic purification of a recombinant protein by cationic elastin-like polypeptides.

Journal Article (Journal Article)

This paper reports an improvement in the purification of thioredoxin (Trx) expressed from E. coli by inverse transition cycling (ITC) using cationic elastin-like polypeptides (ELPs). Two ELP libraries having 2% and 5% lysine residues and molecular weights ranging from 4 to 61.1 kDa showed greater salt sensitivity in their inverse transition behavior than purely aliphatic ELPs. Expression yield of Trx-ELP fusions was an unpredictable function of guest residue composition, but reducing the molecular weight of the ELP tag generally increased Trx yield. A cationic 4.3 kDa ELP is the shortest ELP used to purify any protein by ITC to date. A 15.9 kDa ELP with a guest residue composition of K:V:F of 1:7:1 was found to be the optimal cationic tag to purify Trx, as it provided 50% greater Trx yield and only required one-fifth the added NaCl for purification of Trx as compared to previously used aliphatic ELP tags.

Full Text

Duke Authors

Cited Authors

  • Lim, DW; Trabbic-Carlson, K; Mackay, JA; Chilkoti, A

Published Date

  • May 2007

Published In

Volume / Issue

  • 8 / 5

Start / End Page

  • 1417 - 1424

PubMed ID

  • 17407348

Pubmed Central ID

  • PMC2562536

Electronic International Standard Serial Number (EISSN)

  • 1526-4602

International Standard Serial Number (ISSN)

  • 1525-7797

Digital Object Identifier (DOI)

  • 10.1021/bm060849t


  • eng