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The Importance of Correct Protein Concentration for Kinetics and Affinity Determination in Structure-function Analysis
Published on: March 17, 2010
Fighting an enemy within: cytoplasmic inhibitors of bacterial cysteine proteases
Jan Potempa1, Ewa Golonka, Renata Filipek
1Department of Microbiology, Faculty of Biotechnology, Jagiellonian University, ul. Gronostajowa 7, 30-387 Kraków, Poland. potempa@uga.edu
Abstract:
The genes encoding secreted, broad-spectrum activity cysteine proteases of Staphylococcus spp. (staphopains) and Streptococcus pyogenes (streptopain, SpeB) are genetically linked to genes encoding cytoplasmic inhibitors. While staphopain inhibitors have lipocalin-like folds, streptopain is inhibited by a protein bearing the scaffold of the enzyme profragment. Bioinformatic analysis of other prokaryotic genomes has revealed that two more species may utilize this same genetic arrangement to control streptopain-like proteases with lipocalin-like inhibitors, while three other species may employ a C-terminally located domain that resembles the profragment. This apparently represents a novel system that bacteria use to control the intracellular activity of their proteases.
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