2I2J

NMR structure of UA159sp in TFE

2I2J の概要

• エントリーDOI: 10.2210/pdb2i2j/pdb
• NMR情報: BMRB: 15068
• 分子名称: Competence stimulating peptide (1 entity in total)
• 機能のキーワード: helix, signaling protein
• 由来する生物種: Streptococcus mutans
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 2365.69

構造登録者

Syvitski, R.T.,Jakeman, D.L.,Li, Y. (登録日: 2006-08-16, 公開日: 2006-10-17, 最終更新日: 2024-10-16)

主引用文献

Syvitski, R.T.,Tian, X.L.,Sampara, K.,Salman, A.,Lee, S.F.,Jakeman, D.L.,Li, Y.H.
Structure-Activity Analysis of Quorum-Sensing Signaling Peptides from Streptococcus mutans.
J.Bacteriol., 189:1441-1450, 2007

PubMed Abstract: Streptococcus mutans secretes and utilizes a 21-amino-acid signaling peptide pheromone to initiate quorum sensing for genetic competence, biofilm formation, stress responses, and bacteriocin production. In this study, we designed and synthesized a series of truncated peptides and peptides with amino acid substitutions to investigate their structure-activity relationships based on the three-dimensional structures of S. mutans wild-type signaling peptide UA159sp and C-terminally truncated peptide TPC3 from mutant JH1005 defective in genetic competence. By analyzing these peptides, we demonstrated that the signaling peptide of S. mutans has at least two functional domains. The C-terminal structural motif consisting of a sequence of polar hydrophobic charged residues is crucial for activation of the signal transduction pathway, while the core alpha-helical structure extending from residue 5 to the end of the peptide is required for receptor binding. Peptides in which three or more residues were deleted from the C terminus did not induce genetic competence but competitively inhibited quorum sensing activated by UA159sp. Disruption of the amphipathic alpha-helix by replacing the Phe-7, Phe-11, or Phe-15 residue with a hydrophilic residue resulted in a significant reduction in or complete loss of the activity of the peptide. In contrast to the C-terminally truncated peptides, these peptides with amino acid substitutions did not compete with UA159sp to activate quorum sensing, suggesting that disruption of the hydrophobic face of the alpha-helical structure results in a peptide that is not able to bind to the receptor. This study is the first study to recognize the importance of the signaling peptide C-terminal residues in streptococcal quorum sensing.

PubMed: 16936029
DOI: 10.1128/JB.00832-06

実験手法

SOLUTION NMR