An exposed tyrosine residue of RNase T1 and its involvement in the interaction with guanylic acid

FEBS Letters

Hayashi, Fumiaki¹  Sakiyama, Fumio¹  Kawata, Yasushi¹  Nagai, Hiroshi¹  Kyogoku, Yoshimasa¹ 

[1] Institute for Protein Research, Osaka University, Suita, Osaka 565, Japan

关键词: Photo-CIDNP;    RNase T1;    Guanylic acid;    Nitration;    NMR;    Enzyme-substrate binding;   

DOI  :  10.1016/0014-5793(85)81017-6

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

A photo-CIDNP spectrum of RNase T₁ showed that 4 out of the total 9 tyrosines are accessible to the photosensitive dye, while none of the histidine and tryptophan residues are accessible. By comparison with the results of nitration of tyrosine side chains followed by peptide analysis, it can be concluded that Tyr 45 is mostly exposed on the surface of RNase T₁. On addition of 2'-GMP, the signal of Tyr 45 shifts upfield and is remarkably broadened, which suggests that the phenyl ring of Tyr 45 stacks on the guanine ring of 2'-GMP. Similar phenomena were observed on addition of 3'-GMP and 3'-dGMP.

【 授权许可】

Unknown