ジャーナル: EMBO J / 年: 2021 タイトル: Endospore Appendages: a novel pilus superfamily from the endospores of pathogenic Bacilli. 著者: Brajabandhu Pradhan / Janine Liedtke / Mike Sleutel / Toril Lindbäck / Ephrem Debebe Zegeye / Kristin O Sullivan / Ann-Katrin Llarena / Ola Brynildsrud / Marina Aspholm / Han Remaut / 要旨: Bacillus cereus sensu lato is a group of Gram-positive endospore-forming bacteria with high ecological diversity. Their endospores are decorated with micrometer-long appendages of unknown identity ...Bacillus cereus sensu lato is a group of Gram-positive endospore-forming bacteria with high ecological diversity. Their endospores are decorated with micrometer-long appendages of unknown identity and function. Here, we isolate endospore appendages (Enas) from the food poisoning outbreak strain B. cereus NVH 0075-95 and find proteinaceous fibers of two main morphologies: S- and L-Ena. By using cryoEM and 3D helical reconstruction of S-Enas, we show these to represent a novel class of Gram-positive pili. S-Enas consist of single domain subunits with jellyroll topology that are laterally stacked by β-sheet augmentation. S-Enas are longitudinally stabilized by disulfide bonding through N-terminal connector peptides that bridge the helical turns. Together, this results in flexible pili that are highly resistant to heat, drought, and chemical damage. Phylogenomic analysis reveals a ubiquitous presence of the ena-gene cluster in the B. cereus group, which include species of clinical, environmental, and food importance. We propose Enas to represent a new class of pili specifically adapted to the harsh conditions encountered by bacterial spores.
A: DUF3992 domain-containing protein B: DUF3992 domain-containing protein C: DUF3992 domain-containing protein D: DUF3992 domain-containing protein E: DUF3992 domain-containing protein F: DUF3992 domain-containing protein G: DUF3992 domain-containing protein H: DUF3992 domain-containing protein I: DUF3992 domain-containing protein J: DUF3992 domain-containing protein K: DUF3992 domain-containing protein L: DUF3992 domain-containing protein M: DUF3992 domain-containing protein N: DUF3992 domain-containing protein O: DUF3992 domain-containing protein P: DUF3992 domain-containing protein Q: DUF3992 domain-containing protein R: DUF3992 domain-containing protein S: DUF3992 domain-containing protein T: DUF3992 domain-containing protein U: DUF3992 domain-containing protein V: DUF3992 domain-containing protein W: DUF3992 domain-containing protein