Ottmann, Christian; Rose, Rolf; Huttenlocher, Franziska; Cedzich, Anna; Hauske, Patrick; Kaiser, Markus; Huber, Robert; Schaller, Andreas:
Structural basis for Ca2+-independence and activation by homodimerization of tomato subtilase 3
2009
In: Proceedings of the National Academy of Sciences of the United States of America : PNAS, Jg. 106 (2009), Heft 40, S. 17223 - 17228
Artikel/Aufsatz in Zeitschrift / Fach: Biologie
Fakultät für Biologie
Titel:
Structural basis for Ca2+-independence and activation by homodimerization of tomato subtilase 3
Autor(in):
Ottmann, Christian; Rose, Rolf; Huttenlocher, Franziska; Cedzich, Anna; Hauske, Patrick im Online-Personal- und -Vorlesungsverzeichnis LSF anzeigen; Kaiser, Markus im Online-Personal- und -Vorlesungsverzeichnis LSF anzeigen; Huber, Robert; Schaller, Andreas
Erscheinungsjahr
2009
Erschienen in:
Proceedings of the National Academy of Sciences of the United States of America : PNAS, Jg. 106 (2009), Heft 40, S. 17223 - 17228
ISSN
WWW URL

Abstract:

Subtilases are serine proteases found in Archae, Bacteria, yeasts, and higher eukaryotes. Plants possess many more of these subtilisin-like endopeptidases than animals, e.g., 56 identified genes in Arabidopsis compared with only 9 in humans, indicating important roles for subtilases in plant biology. We report the first structure of a plant subtilase, SBT3 from tomato, in the active apo form and complexed with a chloromethylketone (cmk) inhibitor. The domain architecture comprises an N-terminal protease domain displaying a 132 aa protease-associated (PA) domain insertion and a C-terminal seven-stranded jelly-roll fibronectin (Fn) III-like domain. We present the first structural evidence for an explicit function of PA domains in proteases revealing a vital role in the homo-dimerization of SBT3 and in enzyme activation. Although Ca2+-binding sites are conserved and critical for stability in other subtilases, SBT3 was found to be Ca2+-free and its thermo stability is Ca2+-independent.