Isolation and Characterization of Lectin in Soybean(Glycine max L.)

대두(Glycine max L.)의 렉틴 분리 및 특성

This experiment was carried out to investigate the lectin of soybean (Glycine max L.) seed. Purification was done by 50-80% ammonium sulfate precipitation, CM-cellulose and Sephadex G-100 column. The purity was ascertained by electrophoresis. The molecular weight of purified lectin was estimated as 132,000. It was composed of three subunits which molecular weight was 45,000. The lectin was identified as glycoprotein by Schiff's reagent staining and Dubois method. The lectin agglutinated erythrocytes of rabbit and human. The amounts of the lectin to agglutinate human erythrocytes differed among the blood types: The blood type A required the least amount, the next was B, O, and AB in order. The agglutination was specifically inhibited by 5${\mu}$g/ml of N -acetyl.-D-galactoseamine and 200${\mu}$g/ml of D-galactose. Other tested sugars could not inhibit the agglutination of the erythrocytes by the lectin.

본 실험은 대두(Glycine max L.) 방사품종의 종자단백질에서 렉틴을 분리하여 그 특성을 조사하기 위하여 수행되었다. 렉틴의 분리방법은 (NH$_4$)$_2$SO$_4$의 50~80% 포화침전단백질을 Carboxymethyl cellulose column과 Sephadex G 100 column을 거쳐서 분리, 정제되었다. 순도의 검정은 2~30% polyacrylamide porosity gradient gel을 사용한 전기영동법으로 단일 band를 확인하였고 또한 분자량은 11% sodium dodecyl sulfate polyacrylamide gel에 의하여 134,000 dalton임을 추정하였으며 45,000 dalton의 3개의 subunits로 구성되어 있음을 알았다. Schiff reagent에 의하여 분홍색 반응을 일으켰으므로 이것은 당단백질임을 알 수 있었다. 본 당단백질은 토끼와 사람의 적혈구 모두에서 적혈구응집 반응이 일어났으며 사람의 혈액형중에서 적형구응집 정도는 A>B>O>AB형의 순서로 응집이 잘 일어났다. 당류에 의한 적혈구응집저해는 N -acetyl-D-galactoseamine 과 D-galactose에 의하여 일어났다.