Context-dependent anticodon recognition by class I lysyl-tRNA synthetases.
Context-dependent anticodon recognition by class I lysyl-tRNA synthetases.
复制标题
I 类赖氨酰-tRNA 合成酶的上下文依赖性反密码子识别。
DOI：
10.1073/pnas.97.26.14224
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发表时间：
2000
影响因子：
11.1
通讯作者：
Ibba,M
中科院分区：
文献类型：
--
作者：
Söll,D;Becker,HD;Plateau,P;Blanquet,S;Ibba,M
赖氨酰-tRNA合成由两个不相关的氨酰-tRNA合成酶家族催化。在大多数细菌和所有真核生物中，已知的赖氨酰-tRNA合成酶（LysRS）是IIb类氨酰-tRNA合成酶，而许多古细菌和分散的细菌含有不相关的I类-型LysRS。部分修饰的tRNALysanticodon变体的细菌（从伯氏疏螺旋体）和古细菌（从甲烷球菌maripaludis）I类赖氨酰-tRNA合成酶的识别检查显示两种酶之间的反密码子识别模式的差异。U35和U36对B.而只有U36在M. maripaludisLysRS. I类LysRS的系统发育分布研究表明，U35和U36的识别与天冬酰胺酰-tRNA合成酶（AsnRS）的存在之间存在相关性，AsnRS也识别U35和U36的tRNAAsn的反密码子。然而，缺乏AsnRS的幽门螺杆菌的II类LysRS也识别U35和U36，表明AsnRS的存在仅影响I类LysRS的系统发育分布。这些数据表明，不相关的氨酰-tRNA合成酶之间的竞争重叠的反密码子序列是现存的合成酶家族的系统发育分布的决定因素。这种竞争模式也为I类赖氨酰-tRNA合成酶进化中假设的两个独立的水平基因转移事件提供了基础。
Lysyl-tRNA synthesis is catalyzed by two unrelated families of aminoacyl-tRNA synthetases. In most bacteria and all eukarya, the known lysyl-tRNA synthetases (LysRSs) are subclass IIb-type aminoacyl-tRNA synthetases, whereas many archaea and a scattering of bacteria contain an unrelated class I-type LysRS. Examination of the recognition of partially modified tRNALysanticodon variants by a bacterial (fromBorrelia burgdorferi) and an archaeal (fromMethanococcus maripaludis) class I lysyl-tRNA synthetase revealed differences in the pattern of anticodon recognition between the two enzymes. U35 and U36 were both important for recognition by theB. burgdorferienzyme, whereas only U36 played a role in recognition byM. maripaludisLysRS. Examination of the phylogenetic distribution of class I LysRSs suggested a correlation between recognition of U35 and U36 and the presence of asparaginyl-tRNA synthetase (AsnRS), which also recognizes U35 and U36 in the anticodon of tRNAAsn. However, the class II LysRS ofHelicobacter pylori, an organism that lacks AsnRS, also recognizes both U35 and U36, indicating that the presence of AsnRS has solely influenced the phylogenetic distribution of class I LysRSs. These data suggest that competition between unrelated aminoacyl-tRNA synthetases for overlapping anticodon sequences is a determinant of the phylogenetic distribution of extant synthetase families. Such patterns of competition also provide a basis for the two separate horizontal gene transfer events hypothesized in the evolution of the class I lysyl-tRNA synthetases.