Characterization of proteases secreted by leek roots
- 107 Downloads
Some characteristics of root-secreted proteases were studied. We measured their molecular weights and mechanism of BSA digestion in comparison to endogenous root proteases. We related these studies to culture medium N composition. The seedlings of Allium porrum L. (cv. Bartek) were cultivated on MS medium, MS without inorganic nitrogen (MS-IN), and MS without IN, but with 0.1% casein (MS-IN + 0.1% casein). Electrophoretic study showed that root-secreted proteases had one isoform with a mol wt of 45 kD, regardless of medium N composition. Difference in molecular weights of root-secreted proteases and endogenous root proteases active under used conditions (>66 kD) provide us another strong evidence that root-secreted proteases were not just leaking from the roots, but they were secreted. Proteases exuded by roots degraded BSA in a similar way as endogenous proteases, with only one SDS-PAGE-detectable product of degradation. Our results may be a powerful tool in the extraction and purification of these enzymes and also in proteomic studies.
KeywordsAllium porrum organic nitrogen plant nitrogen nutrition protease secretion proteolytic activity
MS without inorganic nitrogen
Unable to display preview. Download preview PDF.
- 6.Paungfoo-Lonhienne, C., Lonhienne, T.G.A., Rentsch, D., Robinson, N., Christie, M., Webb, R.I., Gamage, H.K., Caroll, B.J., Schenk, P.M., and Schmidt, S., Plants can use protein as nitrogen source without assistance from other organisms, Proc. Natl. Acad. Sci. USA, 2008, vol. 105, pp. 4524–4529.PubMedCentralPubMedCrossRefGoogle Scholar
- 8.Head, G.C., Estimating seasonal changes in the quantity of white unsuberized root on fruit trees, J. Hortic. Sci., 1966, vol. 41, pp. 197–206.Google Scholar
- 11.Adamczyk, B., Smolander, A., Kitunen, V., and Godlewski, M., Proteoid roots and exudation of proteases by plant roots, Secretions and Exudates in Biological Systems, Signaling and Communication in Plants, vol. 12, Vivanco, J.M., Baluška, F., Eds., Berlin; Heidelberg: Springer-Verlag, 2012, pp. 75–89.Google Scholar
- 12.Adamczyk, B. and Godlewski, M., Inter specific variability in protein use by two vegetable crop species, Braz. J. Plant Physiol., 2011, vol. 22, pp. 171–176.Google Scholar