Telenti A, Southworth M, Alcaide F, Daugelat S, Jacobs W R, Perler F B
Institut für Medizinische Mikrobiologie, Universität Bern, Switzerland.
J Bacteriol. 1997 Oct;179(20):6378-82. doi: 10.1128/jb.179.20.6378-6382.1997.
The 198-amino-acid in-frame insertion in the gyrA gene of Mycobacterium xenopi is the smallest known naturally occurring active protein splicing element (intein). Comparison with other mycobacterial gyrA inteins suggests that the M. xenopi intein underwent a complex series of events including (i) removal of 222 amino acids that encompass most of the central intein domain, and (ii) addition of a linker of unrelated residues. This naturally occurring genetic rearrangement is a representative characteristic of the taxon. The deletion process removes the conserved motifs involved in homing endonuclease activity. The linker insertion represents a structural requirement, as its mutation resulted in failure to splice. The M. xenopi GyrA intein thus provides a paradigm for a minimal protein splicing element.
蟾分枝杆菌gyrA基因中198个氨基酸的框内插入是已知最小的天然存在的活性蛋白质剪接元件（内含肽）。与其他分枝杆菌gyrA内含肽的比较表明，蟾分枝杆菌内含肽经历了一系列复杂事件，包括：（i）去除包含大部分中央内含肽结构域的222个氨基酸，以及（ii）添加不相关残基的连接子。这种天然发生的基因重排是该分类单元的一个代表性特征。缺失过程去除了归巢内切核酸酶活性所涉及的保守基序。连接子插入代表一种结构要求，因为其突变导致剪接失败。因此，蟾分枝杆菌GyrA内含肽为最小蛋白质剪接元件提供了一个范例。
