The JI
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     
 

This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Horiuchi, T.
Right arrow Articles by Volanakis, J. E.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Horiuchi, T.
Right arrow Articles by Volanakis, J. E.

The Journal of Immunology, Vol 147, Issue 2 584-589, Copyright © 1991 by American Association of Immunologists

ARTICLES

Site-directed mutagenesis of the region around Cys-241 of complement component C2. Evidence for a C4b binding site

T Horiuchi, KJ Macon, JA Engler and JE Volanakis
Department of Medicine, University of Alabama, Birmingham 35294.

We probed the functional significance of the region around Cys-241 in human C2 by testing the hemolytic activity of a series of mutant rC2. Mutant C2 cDNA were constructed by oligonucleotide-directed site- specific mutagenesis and expressed transiently in COS cells. Wild-type rC2 had threefold higher specific hemolytic activity than native serum C2. Substitution of Gly, Ala, or Ser for Cys-241 resulted in a slightly, but significantly, increased activity. In addition, I2 had no effect on the activity of these mutant C2. Substitution of Lys for Gln- 243 increased the hemolytic activity by more than two-fold. Increased activity in all cases was due to slower decay rates of the C3 convertase. Finally, substitution of Leu or Ala for Asp-240 or Ser-244, respectively, resulted in more than 100-fold decrease of hemolytic activity. The results suggest that residues 240 to 244 of human C2 represent an important structural determinant of the C4b binding site of C2a. They also confirm that Cys-241 is the residue responsible for the increased activity of C2 reacted with I2.


This article has been cited by other articles:


Home page
 J. Biol. Chem.Home page
L. A. Kuttner-Kondo, M. P. Dybvig, L. M. Mitchell, N. Muqim, J. P. Atkinson, M. E. Medof, and D. E. Hourcade
A Corresponding Tyrosine Residue in the C2/Factor B Type A Domain Is a Hot Spot in the Decay Acceleration of the Complement C3 Convertases
J. Biol. Chem., December 26, 2003; 278(52): 52386 - 52391.
[Abstract] [Full Text] [PDF]

Home page
 J. Immunol.Home page
J. M. Inal and J. A. Schifferli
Complement C2 Receptor Inhibitor Trispanning and the {beta}-Chain of C4 Share a Binding Site for Complement C2
J. Immunol., May 15, 2002; 168(10): 5213 - 5221.
[Abstract] [Full Text] [PDF]

Home page
 J. Immunol.Home page
Q. Pan, R. O. Ebanks, and D. E. Isenman
Two Clusters of Acidic Amino Acids Near the NH2 Terminus of Complement Component C4 {alpha}'-Chain Are Important for C2 Binding
J. Immunol., September 1, 2000; 165(5): 2518 - 2527.
[Abstract] [Full Text] [PDF]

Home page
 J. Immunol.Home page
D. E. Hourcade, L. M. Mitchell, and T. J. Oglesby
Mutations of the Type A Domain of Complement Factor B That Promote High-Affinity C3b-Binding
J. Immunol., March 1, 1999; 162(5): 2906 - 2911.
[Abstract] [Full Text] [PDF]

Home page
 J. Biol. Chem.Home page
D. E. Hourcade, L. M. Mitchell, and T. J. Oglesby
A Conserved Element in the Serine Protease Domain of Complement Factor B
J. Biol. Chem., October 2, 1998; 273(40): 25996 - 26000.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
This Website Copyright © 1991 by The American Association of Immunologists, Inc. All rights reserved.
All Contents Copyright © 1991 by The American Association of Immunologists, Inc. All rights reserved.