Vornlocher H P, Scheible W R, Faulhammer H G, Sprinzl M
Laboratorium für Biochemie, Universität Bayreuth, Germany.
Eur J Biochem. 1997 Jan 15;243(1-2):66-71. doi: 10.1111/j.1432-1033.1997.66_1a.x.
Translation initiation factor 2 (IF2) is one of three protein factors required for initiation of protein synthesis in eubacteria. The protein is responsible for binding the initiator RNA to the ribosomal P site. IF2 is a member of the GTP GDP-binding protein superfamily. In the extreme thermophilic bacterium Thermus thermophilus, IF2 was identified as a 66-kDa protein by affinity labeling and immunoblotting. The protein was purified to homogeneity. The specific activity indicates a stoichiometric IF2-mediated binding of formylmethionine-tRNA to 70S ribosomes. The N-terminal amino acid sequences of the intact protein and of two proteolytic fragments of 25 kDa and 40 kDa were determined. Comparison with other bacterial IF2 sequences indicates a similar domain architecture in all bacterial IF2 proteins.
翻译起始因子2（IF2）是真细菌中蛋白质合成起始所需的三种蛋白质因子之一。该蛋白质负责将起始RNA结合到核糖体的P位点。IF2是GTP GDP结合蛋白超家族的成员。在极端嗜热细菌嗜热栖热菌中，通过亲和标记和免疫印迹法将IF2鉴定为一种66 kDa的蛋白质。该蛋白质被纯化至同质。比活性表明IF2介导甲酰甲硫氨酸 - tRNA与70S核糖体的化学计量结合。测定了完整蛋白质以及25 kDa和40 kDa的两个蛋白水解片段的N端氨基酸序列。与其他细菌IF2序列的比较表明，所有细菌IF2蛋白具有相似的结构域结构。
