NMR structure note: alkaline proteinase inhibitor APRin from Pseudomonas aeruginosa
The alkaline proteinase inhibitor (APRin) from Pseudomonas aeruginosa is an 11.5-kDa, high affinity, high specificity inhibitor of the serralysin class of zinc-dependent proteinases secreted by several Gram-negative bacteria (Feltzer et al. 2000). The inhibitor APRin is co-secreted from the bacterium presumably to prevent adventitious proteolysis of host proteins during the secretion process. The serralysins are mechanistically and structurally related to the matrix metalloproteinases (Morihara et al. 2000), and the active site zinc atom is accessible through a tunnel to the enzyme surface. These enzymes are capable of degrading a variety of host proteins and thereby enhance the pathogenicity of these organisms (Morihara and Homma 1985).
The X-ray structure of the proteinase-APRin complex revealed that the five N-terminal inhibitor residues occupy the extended substrate binding site of the enzyme and that the terminal amino group (Ser) coordinates to the catalytic...
KeywordsExtended Chain Rotational Correlation Time Residual Dipolar Coupling Catalytic Zinc Backbone Chemical Shift
This work was supported by the Kentucky Challenge for Excellence (to ANL). NMR spectra were recorded at the JG Brown Cancer Center NMR Facility with support from The National Science Foundation EPSCoR grant # EPS−0447479 and the Brown Foundation.
- Cavanagh J, Fairbrother WJ, Palmer AG, Skelton AGNJ (1996) Protein NMR spectroscopy principles and practice. Academic Press, San DiegoGoogle Scholar
- Kay LE, Nicholson LK, Delaglio F, Bax A, Torchia DA (1992) Pulse sequences for removal of the effects of cross-correlation between dipolar and chemical-shift anisotropy relaxation mechanism on the measurement of heteronuclear T1 and T2 values in proteins. J Magn Reson 97:359–375Google Scholar
- Morihara K, Homma J (1985) Bacterial enzymes and virulence bacterial enzymes and virulence I. Holder. CRC Press, Boca Raton, pp 41–47Google Scholar
- Morihara K, Hata Y, Okuda K (2000) Serralysin Zn-metalloproteinases—structure, function, secretion pathway, and pathogenicity. Seikagaku 72:16–25Google Scholar