• Bulletin of the Korean Chemical Society
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• v.32 no.12
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• pp.4253-4257
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• 2011

Sodium dodecyl sulfate-capillary gel electrophoresis (SDS-CGE) and capillary isoelectric focusing (CIEF) were employed to characterize and compare ricin E purified from the small grain seeds of Ricinus communis with ricin D isoform. During the purification of ricin E using ion-exchange and size-exclusion chromatography, SDS-CGE was found to be useful for monitoring the efficiencies of purification steps. SDS-CGE showed that the molecular size of ricin E was not significantly different from that of ricin D, which was confirmed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. CIEF was useful for discriminating ricin E from ricin D based on their isoelectric points (pI). The pI values of ricin E and D were 8.6-8.8 and 7.0-7.4, respectively. This study demonstrates the usefulness of SDS-CGE and CIEF for the characterization of ricin toxins.

• Current Research on Agriculture and Life Sciences
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• v.11
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• pp.121-132
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• 1993

This study was carried out to research the effect of the chemotaxis of Bradyrhizobium japonicum KCTC 2422 and its mutant toward soybean root exudate and to elucidate the effect of the lectin of host specificity (Host Recognition) in soybean-Bradyrhizobium symbiosis. The results obtained were as follows: The homogeneities of the purified lectins from soybean and pea seed was ascertained chromatographically and electrophoretically. Gel electrophoresis of soybean lectin in the presence of sodium dodecyl sulfate appeared a single protein band, whereas pea lectin appeared two protein bands. Soybean lectin from 2 cultivars formed immunoprecipitin arcs at same position with anti-soybean lectin rabbit IgG, but pea lectin did not form immunoprecipitin lines with anti-soybean lectin rabbit IgG. Chemotactic responses of KCTC 2422, LPN-100 and LCR-101 toward proline in capillary assays were 3.1, 1.3 and 1.0-fold above background, respectively. The chemotactic responses of KCTC 2422, LPN-100, and LCR-101 toward Paldal crude root exudate in capillary assays were 3.5, 1.4 and 1.4-fold above background, respectively. The present work shows that B. japonicum and its mutants are capable of very different responses toward root exudate fraction. The chemotactic responses of KCTC 2422 was most with neutral fraction, least with anionic fraction and intermediate with cationic fraction. The nitrogenase activity of soybean nodule was shown in 15days after inoculation with LCR-101. However, we couldn't find out the nodules when soybean was inoculated with LPN-100. From these result we can suppose that the chemotaxis of Bradyrhizobium plays inportant the role of forming the nodule (host recognition) in the soybean-B. japonicum symbiosis.