TY  - JOUR
AU  - Strucksberg, K.H.
AU  - Rosenkranz, T.
AU  - Fitter, J.
TI  - Reversible and irreversible unfolding of multi-domain proteins
JO  - Biochimica et biophysica acta / Proteins and proteomics
VL  - 1774
SN  - 1570-9639
CY  - Amsterdam [u.a.]
PB  - Elsevier
M1  - PreJuSER-60251
SP  - 1501 - 1603
PY  - 2007
N1  - Record converted from VDB: 12.11.2012
AB  - In contrast to single-domain proteins unfolding of larger multi-domain proteins is often irreversible. In a comparative case study on three different multi-domain proteins (phosphoglycerate kinase: PGK and two homologous alpha-amylases: TAKA and BLA) we investigated properties of unfolded states and their ability to fold back into the native state. For this purpose guanidine hydrochloride, alkaline pH, and thermal unfolded states were characterized. Structural alterations upon unfolding and refolding transitions were monitored using fluorescence and CD spectroscopy. Static and dynamic light scattering was employed to follow aggregation processes. Furthermore, proper refolding was also investigated by enzyme activity measurements. While for PGK at least partial reversible unfolding transitions were observed in most cases, we found reversible unfolding for TAKA in the case of alkaline pH and GndHCl induced unfolding. BLA exhibits reversible unfolding only under conditions with high concentrations of protecting osmolytes (glycerol), indicating that aggregation of the unfolded state is the main obstacle to achieve proper refolding for this protein. Structural properties, such as number and size of domains, secondary structure contents and compositions within domains, and domain topology were analyzed and considered in the interpretation of differences in refolding behavior of the investigated proteins.
KW  - Aspergillus oryzae: enzymology
KW  - Bacillus: enzymology
KW  - Buffers
KW  - Glycerol: pharmacology
KW  - Guanidine: pharmacology
KW  - Hydrogen-Ion Concentration
KW  - Models, Molecular
KW  - Osmolar Concentration
KW  - Phosphoglycerate Kinase: chemistry
KW  - Protein Denaturation: drug effects
KW  - Protein Folding
KW  - Protein Structure, Tertiary: drug effects
KW  - Protein Structure, Tertiary: physiology
KW  - Temperature
KW  - Transition Temperature
KW  - alpha-Amylases: chemistry
KW  - Buffers (NLM Chemicals)
KW  - Guanidine (NLM Chemicals)
KW  - Glycerol (NLM Chemicals)
KW  - Phosphoglycerate Kinase (NLM Chemicals)
KW  - alpha-Amylases (NLM Chemicals)
KW  - J (WoSType)
LB  - PUB:(DE-HGF)16
C6  - pmid:17964867
UR  - <Go to ISI:>//WOS:000252238600012
DO  - DOI:10.1016/j.bbapap.2007.09.005
UR  - https://juser.fz-juelich.de/record/60251
ER  -