Evolution of eukaryal tRNA-guanine transglycosylase: insight gained from the heterocyclic substrate recognition by the wild-type and mutant human and Escherichia coli tRNA-guanine transglycosylases.
Evolution of eukaryal tRNA-guanine transglycosylase: insight gained from the heterocyclic substrate recognition by the wild-type and mutant human and Escherichia coli tRNA-guanine transglycosylases.
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DOI：
10.1093/nar/gkq1188
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发表时间：
2011-04
影响因子：
14.9
通讯作者：
Garcia GA
中科院分区：
文献类型：
--
作者：
Chen YC;Brooks AF;Goodenough-Lashua DM;Kittendorf JD;Showalter HD;Garcia GA
tRNA-鸟嘌呤转糖基酶（TGT）参与真核生物和真细菌中tRNA的肌苷修饰以及古细菌中tRNA的古核苷修饰。然而，不同类别的TGT利用不同的杂环底物（在古细菌的情况下是tRNA）。基于X-射线结构分析，早期的研究[Stengl等人（2005）Mechanism and substrate specificity of tRNA-guanine transglycosylases（TGT）：tRNA-modifying enzymes from the three different kingdom of life share a common catalytic mechanism. Chembiochem，6，1926-1939]已经为真细菌和古细菌TGT的分歧进化提出了令人信服的理由。真核类TGT的X射线结构尚不清楚。我们进行了序列同源性和系统发育分析，并进行了酶动力学研究与野生型和突变体TGT从大肠杆菌和人类使用各种杂环底物，我们合成的。用Cys 145 Val（E.大肠杆菌）和相应的Val 161 Cys（人）TGT的进化与这样的想法一致，即Cys 145在真细菌TGT中进化为识别preQ 1但不识别精氨酸，而真核等价物Val 161进化为增加对精氨酸的识别并伴随减少对preQ 1的识别。系统发育和动力学分析都支持这样的结论，即所有的TGT已经分化地进化到特异性地识别它们的同源杂环底物。
The enzyme tRNA-guanine transglycosylase (TGT) is involved in the queuosine modification of tRNAs in eukarya and eubacteria and in the archaeosine modification of tRNAs in archaea. However, the different classes of TGTs utilize different heterocyclic substrates (and tRNA in the case of archaea). Based on the X-ray structural analyses, an earlier study [Stengl et al. (2005) Mechanism and substrate specificity of tRNA-guanine transglycosylases (TGTs): tRNA-modifying enzymes from the three different kingdoms of life share a common catalytic mechanism. Chembiochem, 6, 1926–1939] has made a compelling case for the divergent evolution of the eubacterial and archaeal TGTs. The X-ray structure of the eukaryal class of TGTs is not known. We performed sequence homology and phylogenetic analyses, and carried out enzyme kinetics studies with the wild-type and mutant TGTs from Escherichia coli and human using various heterocyclic substrates that we synthesized. Observations with the Cys145Val (E. coli) and the corresponding Val161Cys (human) TGTs are consistent with the idea that the Cys145 evolved in eubacterial TGTs to recognize preQ1 but not queuine, whereas the eukaryal equivalent, Val161, evolved for increased recognition of queuine and a concomitantly decreased recognition of preQ1. Both the phylogenetic and kinetic analyses support the conclusion that all TGTs have divergently evolved to specifically recognize their cognate heterocyclic substrates.
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影响因子：
4.8
作者：
Boland, Coilin;Hayes, Patti;Kelly, Vincent P.
通讯作者：
Kelly, Vincent P.
影响因子：
2.4
作者：
Hoops, GC;Park, J;Townsend, LB
通讯作者：
Townsend, LB
DOI：
10.1039/p19880001637
发表时间：
1988-07-01
期刊：
JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 1
影响因子：
--
作者：
AKIMOTO, H;IMAMIYA, E;NISHIMURA, S
通讯作者：
NISHIMURA, S
影响因子：
1.8
作者：
Brooks, Allen F.;Garcia, George A.;Showalter, H. D. Hollis
通讯作者：
Showalter, H. D. Hollis
影响因子：
5.1
作者：
Goodenough-Lashua, DM;Garcia, GA
通讯作者：
Garcia, GA