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|
| Type |
Poster Presentation |
| Area |
Life Chemistry |
| Room No. |
Exhibition Hall 2 |
| Time |
4월 19일 (금요일) 11:00~12:30 |
| Code |
LIFE.P-367 |
| Subject |
Psychrophilic Cold Shock Protein has Tyrosine in its Hydrophobic Core: Key Determinant of the Low Thermostability |
| Authors |
Yeongjoon Lee, Yangmee Kim*
Department of Biotechnology, Konkuk University, Korea
|
| Abstract |
Cold shock proteins (Csps) function as RNA chaperones at lower-than-optimum temperatures. Here, we investigated the structure and dynamics of the psychrophilic Csp from Colwellia psychrerythraea 34H (Cp-Csp) for the first time. Despite of high sequence homology, its thermostability (37℃) was markedly lower than those of other Csps. NMR spectroscopic analysis revealed that Cp-Csp has a flexible structure with only one salt bridge and 10 residues in the hydrophobic cavity. Instead of the conserved Phe, Cp-Csp contains Tyr51 in its hydrophobic core. The Y51F mutation increased the stability of hydrophobic packing and may have allowed the formation of a K3–E21 salt bridge, increasing the thermostability to 43℃. Cp-Csp exhibited conformational exchanges in its ribonucleoprotein motifs 1 and 2, and these motions were decreased by the nucleic acid binding. Fewer salt bridges, longer flexible loops, and less compact hydrophobic cavity lead to the low thermostability of Cp-Csp. The conformational flexibility of Cp-Csp facilitates its accommodation of nucleic acids at low temperatures in polar oceans and its function as an RNA chaperone for cold adaptation. |
| E-mail |
lyj7956@konkuk.ac.kr |
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123rd General Meeting of the KCS