|
|
||||||||
1 Department of Biology, Masschusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
2 Department of Chemical Engineering, University of Delaware, Newark, Delaware 19716, USA
3 Syngenta, Research Triangle Park, North Carolina, 27709 USA
Reprint requests to: Dr. Jonathan King, Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA; e-mail: jaking{at}mit.edu; fax: (617) 252-1843.
The predominantly ß-sheet phage P22 tailspike adhesin contains eight reduced cysteines per 666 residue chain, which are buried and unreactive in the native trimer. In the pathway to the native trimer, both in vivo and in vitro transient interchain disulfide bonds are formed and reduced. This occurs in the protrimer, an intermediate in the formation of the interdigitated ß-sheets of the trimeric tailspike. Each of the eight cysteines was replaced with serine by site-specific mutagenesis of the cloned P22 tailspike gene and the mutant genes expressed in Escherichia coli. Although the yields of native-like Cys>Ser proteins varied, sufficient soluble trimeric forms of each of the eight mutants accumulated to permit purification. All eight single Cys>Ser mature proteins maintained the high thermostability of the wild type, as well as the wild-type biological activity in forming infectious virions. Thus, these cysteine thiols are not required for the stability or activity of the native state. When their in vivo folding and assembly kinetics were examined, six of the mutant substitutionsC267S, C287S, C458S, C613S, and C635Swere significantly impaired at higher temperatures. FourC290S, C496, C613S, and C635showed significantly impaired kinetics even at lower temperatures. The in vivo folding of the C613S/C635S double mutant was severely defective independent of temperature. Since the trimeric states of the single Cys>Ser substituted chains were as stable and active as wild type, the impairment of tailspike maturation presumably reflects problems in the in vivo folding or assembly pathways. The formation or reduction of the transient interchain disulfide bonds in the protrimer may be the locus of these kinetic functions.
Keywords: Protein folding; assembly; oligomers; cysteines; tailspike
Abbreviations: SDS, sodium dodecyl sulfate BPTI, bovine pancreatic trypsin inhibitor PFU, plaque-forming units LPS, lipopolysaccharide PMSF, phenylmethylsulfonyl fluoride IPTG, isopropyl ß-D-thiogalatopyranoside.
![]()
CiteULike
Connotea
Del.icio.us
Digg
Reddit
Technorati What's this?
This article has been cited by other articles:
![]() |
J. Kim and A. S. Robinson Dissociation of intermolecular disulfide bonds in P22 tailspike protein intermediates in the presence of SDS Protein Sci., July 1, 2006; 15(7): 1791 - 1793. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Jain, M. S. Evans, J. King, and P. L. Clark Monoclonal Antibody Epitope Mapping Describes Tailspike {beta}-Helix Folding and Aggregation Intermediates J. Biol. Chem., June 17, 2005; 280(24): 23032 - 23040. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Betts, C. Haase-Pettingell, K. Cook, and J. King Buried hydrophobic side-chains essential for the folding of the parallel {beta}-helix domains of the P22 tailspike Protein Sci., September 1, 2004; 13(9): 2291 - 2303. [Abstract] [Full Text] [PDF] |
||||
![]() |
W. H. Pope, C. Haase-Pettingell, and J. King Protein Folding Failure Sets High-Temperature Limit on Growth of Phage P22 in Salmonella enterica Serovar Typhimurium Appl. Envir. Microbiol., August 1, 2004; 70(8): 4840 - 4847. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. L. Danek and A. S. Robinson Nonnative Interactions between Cysteines Direct Productive Assembly of P22 Tailspike Protein Biophys. J., November 1, 2003; 85(5): 3237 - 3247. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. F. Kreisberg, S. D. Betts, C. Haase-Pettingell, and J. King The interdigitated {beta}-helix domain of the P22 tailspike protein acts as a molecular clamp in trimer stabilization Protein Sci., April 1, 2002; 11(4): 820 - 830. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. P. Li, A. Nakanishi, S. W. Clark, and H. Kasamatsu Formation of transitory intrachain and interchain disulfide bonds accompanies the folding and oligomerization of simian virus 40 Vp1 in the cytoplasm PNAS, January 17, 2002; (2002) 32668699. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. P. Li, A. Nakanishi, S. W. Clark, and H. Kasamatsu Formation of transitory intrachain and interchain disulfide bonds accompanies the folding and oligomerization of simian virus 40 Vp1 in the cytoplasm PNAS, February 5, 2002; 99(3): 1353 - 1358. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |