PEDS Advance Access originally published online on April 5, 2004
Protein Engineering Design and Selection 2004 17(3):251-260; doi:10.1093/protein/gzh029
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© 2004 Oxford University Press
Effects of novel peptides derived from the acidic tail of synuclein (ATS) on the aggregation and stability of fusion proteins
Department of Microbiology and Brain Korea 21 Project of Medical Sciences, Yonsei University College of Medicine, 134 Shinchon-dong, Seodaemoon-gu, Seoul 120-752, Korea
1 To whom correspondence should be addressed. e-mail: jkim63{at}yumc.yonsei.ac.kr
The acidic tail of
-synuclein (ATS
) has been shown to protect the glutathione S-transferase (GST)ATS
fusion protein from environmental stresses, such as heat, pH and metal ions. In this study, we further demonstrated that the introduction of ATS
into other proteins, such as dehydrofolate reductase and adiponectin, renders the fusion proteins resistant to heat-induced aggregation and that the acidic tail of ß- or
-synuclein can also protect the fusion proteins from heat-induced aggregation. Interestingly, the heat resistance of GSTATS
deletion mutants, which contain shorter peptides derived from the highly charged regions of ATS
, was approximately proportional to the number of added Glu/Asp residues. However, the negative charges in the ATS
-derived peptides appear insufficient to explain the extreme heat resistance of the fusion proteins, since polyglutamates appeared to be much less effective than the ATS
-derived peptides in conferring heat resistance on the fusion proteins. These results suggest that not only the negatively charged residues but also the specific amino acid sequence of ATS
play an important role in conferring extreme heat resistance on the fusion proteins. Furthermore, the heat-induced secondary structural changes and thermal inactivation curves of GSTATS
deletion mutants indicated that the introduction of ATS
-derived peptides does not significantly affect the intrinsic stability of the fusion proteins.
Received December 16, 2003; revised February 27, 2004; accepted March 16, 2004 Edited by Taiji Imoto