본 논문에서는 기내 배양된 담배의 생장과 chlorophyll 및 rubisco/rubisco activase에 미치는 Cd에 대한 암모늄염의 영향을 연구하였다. Cd에 의해 감소된 담배의 생장은 $NH_4NO_3$에 의해 회복되었으며, 이 현상은 80 mM $NH_4NO_3$에서 현저하게 높았다. Chlorophyll 또한 같은 농도의 질소원에서 회복되었다. 80 mM $NH_4NO_3$에서의 rubisco의 함량이 다른 처리구보다 현저하게 증가하였으며, rubisco의 활성 또한 rubisco의 함량과 같은 변화를 보였다. 이러한 결과들은 rubisco의 함량이 rubisco의 활성과 연관되어있음을 의미하며, Cd에 의해 감소된 rubisco의 함량과 활성이 암모늄염에 의해 회복되었음을 암시한다. SDS-PAGE에 의해 분석된, 80 mM $NH_4NO_3$에서의 55 kD와 15 kD의 large subunit와 small subunit의 intensity는 다른 처리구보다 현저하게 증가하였다. Rubisco에 대한 $NH_4NO_3$의 효과가 rubisco activase에 의해 기인될 것으로 추측되어 이의 함량과 활성을 측정한 결과, 80 mM $NH_4NO_3$에서의 rubisco activase의 함량은 다른 처리구보다 현저하게 증가하였으며, 이의 활성은 함량과 같은 경향을 나타냈다.
Influence of ammonium against cadmium (Cd) effects on in vitro growth, chlorophyll and rubisco/rubisco activase was investigated in tobacco grown on M5 medium. In vitro growth reduced by Cd was recovered by $NH_4NO_3$, and this recovery was most significant when tobacco was treated with 80 mM $NH_4NO_3$. Chlorophyll levels were also recovered by 80 mM $NH_4NO_3$. Rubisco content at 80 mM $NH_4NO_3$ was significantly increased than that at other treatments. Rubisco activity showed patterns of change similar to rubisco content. These data suggest that rubisco content was associated with activity of rubisco, and that the content and activity of rubisco reduced by Cd were recovered by ammonium. The degree of intensity of 55 and 15 kD polypeptides identified as the large and small subunit of rubisco by SDS-PACE analysis at 80 mM $NH_4NO_3$ was significantly higher than that at other treatments. Under the assumption that effects of ammonium on rubisco may be related to rubisco activase, its content and activity were determined. The rubisco activase content at 80 mM $NH_4NO_3$ was more increased than other treatments. A similar change pattern was also observed in activity of rubisco activase.
