Thömmes P, Fett R, Schray B, Kunze N, Knippers R
Fakultät für Biologie, Universität Konstanz, FRG.
Nucleic Acids Res. 1988 Jun 24;16(12):5391-406. doi: 10.1093/nar/16.12.5391.
We have isolated from a Lambda-gt 11 library a human cDNA clone with one open reading frame of about 2400 bases. A stretch of about 350 amino acids in the deduced amino acid sequence is up to 40 percent identical with parts of the known amino acid sequences of E. coli and yeast glutaminyl (Gln)-tRNA synthetase. The isolated cDNA sequence corresponds to an internal section of a 5500 bases long mRNA that codes for a 170 kDa polypeptide associated with Gln-tRNA synthetase. Thus, the human enzyme is about three times larger than the E. coli and two times larger than the yeast Gln-tRNA synthetase. The three enzymes share an evolutionarily conserved core but differ in amino acid sequences linked to the N-terminal and C-terminal side of the core.
我们从一个λ-gt 11文库中分离出一个人类cDNA克隆，它有一个约2400个碱基的开放阅读框。推导的氨基酸序列中约350个氨基酸的一段与大肠杆菌和酵母谷氨酰胺（Gln）-tRNA合成酶的已知氨基酸序列部分高达40%相同。分离出的cDNA序列对应于一个5500个碱基长的mRNA的内部片段，该mRNA编码一种与Gln-tRNA合成酶相关的170 kDa多肽。因此，人类酶比大肠杆菌的酶大约大三倍，比酵母Gln-tRNA合成酶大约大二倍。这三种酶共享一个进化上保守的核心，但在与核心的N端和C端相连的氨基酸序列上有所不同。
