ジャーナル: Structure / 年: 2023 タイトル: Cryo-EM structure of the Agrobacterium tumefaciens T-pilus reveals the importance of positive charges in the lumen. 著者: Jaafar Amro / Corbin Black / Zakaria Jemouai / Nathan Rooney / Caroline Daneault / Natalie Zeytuni / Matthieu Ruiz / Khanh Huy Bui / Christian Baron / 要旨: Agrobacterium tumefaciens is a natural genetic engineer that transfers DNA into plants, which is the most applied process for generation of genetically modified plants. DNA transfer is mediated by a ...Agrobacterium tumefaciens is a natural genetic engineer that transfers DNA into plants, which is the most applied process for generation of genetically modified plants. DNA transfer is mediated by a type IV secretion system in the cell envelope and extracellular T-pili. We here report the cryo-electron microscopic structures of the T-pilus at 3.2-Å resolution and of the plasmid pKM101-determined N-pilus at 3-Å resolution. Both pili contain a main pilus protein (VirB2 in A. tumefaciens, TraM in pKM101) and phospholipids arranged in a five-start helical assembly. They contain positively charged amino acids in the lumen, and the lipids are positively charged in the T-pilus (phosphatidylcholine) conferring overall positive charge. Mutagenesis of the lumen-exposed Arg91 in VirB2 results in protein destabilization and loss of pilus formation. Our results reveal that different phospholipids can be incorporated into type IV secretion pili and that the charge of the lumen may be of functional importance.
1A: Conjugal transfer protein TraM 1B: Conjugal transfer protein TraM 1C: Conjugal transfer protein TraM 1D: Conjugal transfer protein TraM 1E: Conjugal transfer protein TraM 1F: Conjugal transfer protein TraM 1G: Conjugal transfer protein TraM 1H: Conjugal transfer protein TraM 1I: Conjugal transfer protein TraM 1J: Conjugal transfer protein TraM 1K: Conjugal transfer protein TraM 1L: Conjugal transfer protein TraM 1M: Conjugal transfer protein TraM 1N: Conjugal transfer protein TraM 2A: Conjugal transfer protein TraM 2B: Conjugal transfer protein TraM 2C: Conjugal transfer protein TraM 2D: Conjugal transfer protein TraM 2E: Conjugal transfer protein TraM 2F: Conjugal transfer protein TraM 2G: Conjugal transfer protein TraM 2H: Conjugal transfer protein TraM 2I: Conjugal transfer protein TraM 2J: Conjugal transfer protein TraM 2K: Conjugal transfer protein TraM 2L: Conjugal transfer protein TraM 2M: Conjugal transfer protein TraM 2N: Conjugal transfer protein TraM 3A: Conjugal transfer protein TraM 3B: Conjugal transfer protein TraM 3C: Conjugal transfer protein TraM 3D: Conjugal transfer protein TraM 3E: Conjugal transfer protein TraM 3F: Conjugal transfer protein TraM 3G: Conjugal transfer protein TraM 3H: Conjugal transfer protein TraM 3I: Conjugal transfer protein TraM 3J: Conjugal transfer protein TraM 3K: Conjugal transfer protein TraM 3L: Conjugal transfer protein TraM 3M: Conjugal transfer protein TraM 3N: Conjugal transfer protein TraM 4A: Conjugal transfer protein TraM 4B: Conjugal transfer protein TraM 4C: Conjugal transfer protein TraM 4D: Conjugal transfer protein TraM 4E: Conjugal transfer protein TraM 4F: Conjugal transfer protein TraM 4G: Conjugal transfer protein TraM 4H: Conjugal transfer protein TraM 4I: Conjugal transfer protein TraM 4J: Conjugal transfer protein TraM 4K: Conjugal transfer protein TraM 4L: Conjugal transfer protein TraM 4M: Conjugal transfer protein TraM 4N: Conjugal transfer protein TraM 5A: Conjugal transfer protein TraM 5B: Conjugal transfer protein TraM 5C: Conjugal transfer protein TraM 5D: Conjugal transfer protein TraM 5E: Conjugal transfer protein TraM 5F: Conjugal transfer protein TraM 5G: Conjugal transfer protein TraM 5H: Conjugal transfer protein TraM 5I: Conjugal transfer protein TraM 5J: Conjugal transfer protein TraM 5K: Conjugal transfer protein TraM 5L: Conjugal transfer protein TraM 5M: Conjugal transfer protein TraM 5N: Conjugal transfer protein TraM ヘテロ分子
装置: FEI VITROBOT MARK IV / 凍結剤: ETHANE / 湿度: 100 % / 凍結前の試料温度: 277 K 詳細: 3 uL of the sample was repeatedly applied and manually blotted three times using the multiple blotting technique prior to the Vitrobot step to increase the concentration of pili.