• 한국미생물·생명공학회지
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• 제17권1호
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• pp.69-73
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• 1989

자가분해 효소는 Cl. butyricum의 포자형성 배지에서 배양할 때 체외로 배출되어 배양액에도 존재하였다. 배양액으로부터 약 50배로 부분정제된 자가분해 효소를 사용하여 효소의 성질을 조사하였다. 자가분해 효소의 최적 pH와 온도는 각각 5.0과 37$^{\circ}C$였으며 중성 pH에서는 안정하나, 열에는 비교적 불안정하여 5$0^{\circ}C$에서 5분간 열처리한 후 효소활성의 70%가 소실되었다. 또한 Cu ion$^{++}$에 의해서 효소활성이 저하되었으나 그 밖의 금속이온에 의하여서는 큰 영향을 받지 않았다. 또한 자가분해 효소는 기질로서 영양세포에는 직접 활성을 나타내지 못하나, 세포벽 fraction에는 활성을 가지고 있었다.

• The Plant Pathology Journal
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• 제21권4호
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• pp.301-309
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• 2005

Trichoderma species/isolates exhibited varied degree of agglutination on sclerotial (Sc) and hyphal (Hy) surface of Macrophomina phaseolina. The agglutination efficiencies on Sc and Hy ranged from $11\;to\;57\%$. Isolates of T. harzianum (Th) and T. viride (Tv) showed greater agglutination on Sc ($23-57\%$) and Hy ($16-47\%$). Different enzymes (trypsin, pepsin, proteinase k, a-chymotrypsin, lyticase and glucosidase) and inhibitors (tunicamycin, cycloheximide, brefeldin A, sodium azide, dithiothreitol and SDS) reduced the agglutination potential of conidia of Th-23/98 and Tv-25/98; however, the extent of response varied greatly in different treatments. Different fractions of Th-23/98 and Tv-25/98 exhibited haemagglutinating reaction with human blood group A, B, AB and O. Haemagglutinating activity was inhibited by different sugars and glycoproteins tested. Crude haemagglutinating protein from outer cell wall protein fraction of Th-23/98 and Tv-25/98 were eluted on Sephadex G-100 column. Initially Th-23/98 and Tv-25/98 exhibited two peaks showing no agglutination activity; however, lectin activity was detected in the third peak. Similar to crude lectin, the purified lectin also exhibited haemagglutinating activity with different erythrocyte source. SDS-PAGE analysis of partially purified lectin revealed single band with an estimated molecular mass of 55 and 52 kDa in Th-23/98 and Tv-25/98, respectively. Trypsin, chymotrypsin and b-1,3-glucanase totally inhibited lectin activity. Similarly, various pH also affected the haemagglutinating activity of Th-23/98 and Tv-25/98. From the present observations, it can be concluded that the recognition/attachment of mycoparasite (T. harzianum and T. viride) to the host surface (M. phaseolina) may be most likely due to lectin-carbohydrate interaction.