Abstract:
Soybean proteins are limited by their low contents of methionine and cysteine. Herein, 7S globulin accumulation was reduced using RNA interference to silence CG-β-1 expression, and the content of the A2B1a subunit was largely increased under the soybean seed-specific oleosin8 promoter. The results showed that the sulfur-containing amino acid content in soybean seeds drastically improved, reaching 79.194 nmol/mg, and the 11S/7S ratio had a 1.89-fold increase compared to the wild-type acceptor. The secondary structures of 11S globulin were also altered, and the β-sheet content increased with decreasing β-turn content, which was confirmed by Fourier transform infrared spectroscopy, Raman spectroscopy and circular dichroism analysis. Our findings suggested that raising the accumulation of 11S glycinin at the expense of reducing the content of 7S globulin is an attractive and precise engineering strategy to increase the amount of sulfur-containing amino acids, and soybean proteins with A2B1a subunits of 11S isolates improved, and β-subunits of 7S fractions reduced simultaneously might be an effective new material for food production.
摘要:
大豆蛋白受限于其低含量的甲硫氨酸和半胱氨酸。在这里,使用RNA干扰沉默CG-β-1表达减少7S球蛋白积累,在大豆种子特异性oleosin8启动子下,A2B1a亚基的含量大大增加。结果表明,大豆种子中含硫氨基酸含量显著提高,达到79.194nmol/mg,与野生型受体相比,11S/7S比率增加了1.89倍。11S球蛋白的二级结构也发生了改变,β-折叠含量随着β-转角含量的降低而增加,傅里叶变换红外光谱证实了这一点,拉曼光谱和圆二色性分析。我们的发现表明,以降低7S球蛋白含量为代价提高11S大豆球蛋白的积累是增加含硫氨基酸量的一种有吸引力且精确的工程策略,11S分离株A2B1a亚基的大豆蛋白得到了改善,同时减少的7S馏分的β亚基可能是食品生产的有效新材料。