Hostname: page-component-848d4c4894-2pzkn Total loading time: 0 Render date: 2024-04-30T23:59:03.717Z Has data issue: false hasContentIssue false

Proline inhibits aggregation during protein refolding

Published online by Cambridge University Press:  01 February 2000

DHARMARAJ SAMUEL
Affiliation:
Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan
THALLAMPURANAM KRISHNASWAMY S. KUMAR
Affiliation:
Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan Institute of Chemistry, Academia Sinica, Taipei, Taiwan
GOPAL GANESH
Affiliation:
Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan
GURUNATHAN JAYARAMAN
Affiliation:
Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan Present address: Institute of Life Sciences, National Tsing Hua University, Hsinchu, Taiwan.
PEY-WEN YANG
Affiliation:
Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan
MEI-MING CHANG
Affiliation:
Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan
VISHWA DEO TRIVEDI
Affiliation:
Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan Institute of Chemistry, Academia Sinica, Taipei, Taiwan
SUE-LEIN WANG
Affiliation:
Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan
KUO-CHU HWANG
Affiliation:
Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan
DING-KWO CHANG
Affiliation:
Institute of Chemistry, Academia Sinica, Taipei, Taiwan
CHIN YU
Affiliation:
Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan
Get access

Abstract

The in vitro refolding of hen egg-white lysozyme is studied in the presence of various osmolytes. Proline is found to prevent aggregation during protein refolding. However, other osmolytes used in this study fail to exhibit a similar property. Experimental evidence suggests that proline inhibits protein aggregation by binding to folding intermediate(s) and trapping the folding intermediate(s) into enzymatically inactive, “aggregation-insensitive” state(s). However, elimination of proline from the refolded protein mixture results in significant recovery of the bacteriolytic activity. At higher concentrations (>1.5 M), proline is shown to form loose, higher-order molecular aggregate(s). The supramolecular assembly of proline is found to possess an amphipathic character. Formation of higher-order aggregates is believed to be crucial for proline to function as a protein folding aid. In addition to its role in osmoregulation under water stress conditions, the results of this study hint at the possibility of proline behaving as a protein folding chaperone.

Type
Research Article
Copyright
© 2000 The Protein Society

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)