Sandal N N, Bojsen K, Marcker K A
Nucleic Acids Res. 1987 Feb 25;15(4):1507-19. doi: 10.1093/nar/15.4.1507.
The primary structure of two nodule specific soybean genes are presented. The two genes code for primary products of 20.0 (nodulin 20) and 22.7 (nodulin 22) kdaltons, respectively. Both genes are related to the nodulin 23 and 44 genes. Alignment of the deduced amino acid sequences of all four genes revealed three domains of high homology interrupted by highly diverged regions due to numerous duplication and insertion events. The first conserved domain codes for a putative signal peptide, while the two others each contain four Cys residues that can be arranged in a way reminiscent of the metal binding domains present in some enzymes and in several DNA binding proteins.
本文展示了两个大豆根瘤特异性基因的一级结构。这两个基因分别编码20.0千道尔顿（根瘤素20）和22.7千道尔顿（根瘤素22）的初级产物。这两个基因都与根瘤素23和44基因相关。对所有四个基因推导的氨基酸序列进行比对，发现三个高度同源的结构域被高度分化的区域打断，这些区域是由大量的重复和插入事件造成的。第一个保守结构域编码一个假定的信号肽，而另外两个结构域每个都含有四个半胱氨酸残基，它们的排列方式让人联想到某些酶和几种DNA结合蛋白中存在的金属结合结构域。
