Sandbox 16
From Proteopedia
Alpha-lytic protease
Alpha-lytic protease (αlp) is a 198-aa extracellular bacterial serine protease produced by Lysobacter enzymogenes. The three-dimensional fold of αlp puts it in the same class as cymotrypsin, trypsin and other digestive serine proteases despite only modest sequence homology[1]. However, unlike its thermodynamically stable homologs, αlp is stabilized by a large unfolding activation barrier. This kinetic stability optimizes the native state to survive under the harsh, proteolytic conditions in which it operates. Since the native state is less stable than both an intermediate and a completely unfolded state, αlp requires a pro region to facilitate folding by stabilizing the folding transition state as well as the native state. After folding, the pro region is proteolytically cleaved, leaving an active αlp kinetically trapped
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| 2alp, resolution 1.70Å () | |||||||||
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| Ligands: | |||||||||
| Activity: | Alpha-lytic endopeptidase, with EC number 3.4.21.12 | ||||||||
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| Resources: | FirstGlance, OCA, RCSB, PDBsum | ||||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||||
Structure
The contains the double β-barrel motif (colored yellow) that is characteristic of the chymotrypsin family as well as an active site containing the - His 57, Asp 102, and Ser 195 - that is responsible for proteolysis. The preference for αlp to cleave substrates on the C-terminal side of small hydrophobic residues, such as Alanine and Valine is mostly due to consisting of Met 190, Met 213, and Val 218[2].
References
- ↑ Brayer GD, Delbaere LT, James MN. Molecular structure of the alpha-lytic protease from Myxobacter 495 at 2.8 Angstroms resolution. J Mol Biol. 1979 Jul 15;131(4):743-75. PMID:117110
- ↑ Rader SD, Agard DA. Conformational substates in enzyme mechanism: the 120 K structure of alpha-lytic protease at 1.5 A resolution. Protein Sci. 1997 Jul;6(7):1375-86. PMID:9232638
