ジャーナル: Nat Commun / 年: 2020 タイトル: Structure and mechanism of DNA delivery of a gene transfer agent. 著者: Pavol Bárdy / Tibor Füzik / Dominik Hrebík / Roman Pantůček / J Thomas Beatty / Pavel Plevka / 要旨: Alphaproteobacteria, which are the most abundant microorganisms of temperate oceans, produce phage-like particles called gene transfer agents (GTAs) that mediate lateral gene exchange. However, the ...Alphaproteobacteria, which are the most abundant microorganisms of temperate oceans, produce phage-like particles called gene transfer agents (GTAs) that mediate lateral gene exchange. However, the mechanism by which GTAs deliver DNA into cells is unknown. Here we present the structure of the GTA of Rhodobacter capsulatus (RcGTA) and describe the conformational changes required for its DNA ejection. The structure of RcGTA resembles that of a tailed phage, but it has an oblate head shortened in the direction of the tail axis, which limits its packaging capacity to less than 4,500 base pairs of linear double-stranded DNA. The tail channel of RcGTA contains a trimer of proteins that possess features of both tape measure proteins of long-tailed phages from the family Siphoviridae and tail needle proteins of short-tailed phages from the family Podoviridae. The opening of a constriction within the RcGTA baseplate enables the ejection of DNA into bacterial periplasm.
モデルのタイプ: INSILICO MODEL In silico モデル: stochastic gradient descent in RELION 2.1 de novo
最終 再構成
想定した対称性 - 点群: C1 (非対称) / 解像度のタイプ: BY AUTHOR / 解像度: 4.25 Å / 解像度の算出法: FSC 0.143 CUT-OFF / ソフトウェア - 名称: RELION (ver. 3.0) 詳細: relion_align_symmetry was used to shift map mass roughly into rotation center 使用した粒子像数: 35966
初期 角度割当
タイプ: MAXIMUM LIKELIHOOD / ソフトウェア - 名称: RELION (ver. 2.1)
最終 角度割当
タイプ: MAXIMUM LIKELIHOOD / ソフトウェア - 名称: RELION (ver. 3.0)
最終 3次元分類
クラス数: 3 / ソフトウェア - 名称: RELION (ver. 2.1) / 詳細: best class was selected for skip_align refinement