Primary Citation of Related Structures:   1SSO
PubMed Abstract: 
The archaeon Sulfolobus solfataricus expresses large amounts of a small basic protein, Sso7d, which was previously identified as a DNA-binding protein possibly involved in compaction of DNA. We have determined the solution structure of Sso7d. The protein consists of a triple-stranded anti-parallel beta-sheet onto which an orthogonal double-stranded beta-sheet is packed ...
The archaeon Sulfolobus solfataricus expresses large amounts of a small basic protein, Sso7d, which was previously identified as a DNA-binding protein possibly involved in compaction of DNA. We have determined the solution structure of Sso7d. The protein consists of a triple-stranded anti-parallel beta-sheet onto which an orthogonal double-stranded beta-sheet is packed. This topology is very similar to that found in eukaryotic Src homology-3 (SH3) domains. Sso7d binds strongly (Kd < 10 microM) to double-stranded DNA and protects it from thermal denaturation. In addition, we note that epsilon-mono-methylation of lysine side chains of Sso7d is governed by cell growth temperatures, suggesting that methylation is related to the heat-shock response.
Related Citations: 
DNA-Binding Surface of the Sso7D Protein from Sulfolobus Solfataricus Baumann, H., Knapp, S., Karshikoff, A., Ladenstein, R., Hard, T. (1995) J Mol Biol 247: 840
Organizational Affiliation: 
Center for Structural Biochemistry, Karolinska Institutet, NOVUM, Huddinge, Sweden.