Single-stranded DNA (ssDNA)-binding proteins (SSBs) are essential for DNA replication, recombination, and repair processes in all organisms. Sulfolobus solfataricus (S. solfataricus), a hyperthermophilic species, overexpresses its SSB (S. solfataricus SSB (SsoSSB)) to protect ssDNA during DNA metabolisms. Even though the crystal structure of apo SsoSSB and its ssDNA-bound solution structure have been reported at room temperature, structural information at high temperature is not yet available. To find out how SsoSSB maintains its structure and ssDNA binding affinity at high temperatures, we performed multidimensional NMR experiments for SsoSSB at 323K. In this study, we present the backbone and side chain chemical shifts and predict the secondary structure of SsoSSB from the chemical shifts. We found that SsoSSB is ordered, even at high temperatures, and has the same fold at high temperature as at room temperature. Our data will help improve structural analyses and our understanding of the features of thermophilic proteins.

单链 DNA (ssDNA) 结合蛋白 (SSB) 对于所有生物体的 DNA 复制、重组和修复过程至关重要。硫磺菌( S. solfataricus ) 是一种超嗜热物种，它过度表达其 SSB (硫磺菌SSB (SsoSSB)) 以在 DNA 代谢过程中保护单链 DNA。尽管 apo SsoSSB 的晶体结构及其 ssDNA 结合溶液结构已在室温下报道，但高温下的结构信息尚不可用。为了了解 SsoSSB 如何在高温下保持其结构和 ssDNA 结合亲和力，我们在 323K 下对 SsoSSB 进行了多维 NMR 实验。在这项研究中，我们提出了主链和侧链的化学位移，并根据化学位移预测了 SsoSSB 的二级结构。我们发现，即使在高温下，SsoSSB 也是有序的，并且在高温下具有与室温下相同的折叠。我们的数据将有助于改进结构分析和我们对嗜热蛋白质特征的理解。