Abstract
We isolated histone-type basic proteins from lemna paucicostata for the first time. Basic proteins were extracted directly with dilute mineral acids from homogenized lemna paucicostata. Amino acid compositions of basic protein portions adsorbed on Amberlite CG-50(at pH 6. 0) were resembled to those of calf thymus histones. Especially, lysine content was the greatest of the other amino acids. By chromatographic studies, adsorbed portions of basic protein components on carboxymethyl cellulose column(at pH 4. 2) were shown to be homogeneous to calf thymus histones, however, the area under the individual curve was different, and furthermore, the containing of a non-adsorbed portion in the large extent was markedly different from calf thymus histones. And amino acid compositions of adsorbed portions represented the histone-type basic propertes, but non-adsorbed portions were considered as a different protein compared with the typical histone. When calf thymus histone and protein components separated from lemna paucicostata were heated($60^{\circ}C$) with a solution of $HgSO_4-H_2SO_4$, precipitates were not obtained.
"좀개구리밥"에서 histone 型 鹽基性 蛋白質을 單離하는데 처음으로 成功했다. 鹽基性 單白質은 "좀개구리밥"의 細胞磨碎物에서 稀 錦酸으로 抽出 分離하였다. 그 中 Amberlite CG-50에 (pH 6.0에서) 吸着되는 蛋白質成分은 송아지 胸腺 histone과 비슷한 amino 酸組成을 보였고, 構成 amino 酸 殘基로서는 lysine 이 特히 많았다. Carboxymethyl cellulose에 (pH 4.2에서) 吸着되는 蛋白成分의 溶出 chromatogram은 송아지 胸腺 histone과 비슷했으나, 各 peak의 比率은 相遠했으며, 特히 非吸着 成分이 含有되어 있음도 相違했다. 또 吸着成分의 amino 酸組成은 histone 型 鹽基成을 나타냈으나, 非吸着 成分은 典型的인 histone과는 相異한 蛋白質임을 確認했다. 송아지 胸腺 histone과 "좀개구리밥"에서 單離한 蛋白 成分들의 黃酸 存在下에서 $HgSO_4$와의 沈澱反應을 histone아닌 蛋白質과 比較 檢討한 結果, "좀개구리밥"에서 單離한 것은 histone 型 蛋白成分이 分明하였다.