6si7

Publication Abstract from PubMed

Single-molecule long-read DNA sequencing with biological nanopores is fast and high-throughput but suffers reduced accuracy in homonucleotide stretches. We now combine the CsgG nanopore with the 35-residue N-terminal region of its extracellular interaction partner CsgF to produce a dual-constriction pore with improved signal and base-calling accuracy for homopolymer regions. The electron cryo-microscopy structure of CsgG in complex with full-length CsgF shows that the 33 N-terminal residues of CsgF bind inside the beta-barrel of the pore, forming a defined second constriction. In complexes of CsgG bound to a 35-residue CsgF constriction peptide, the second constriction is separated from the primary constriction by ~25 A. We find that both constrictions contribute to electrical signal modulation during single-stranded DNA translocation. DNA sequencing using a prototype CsgG-CsgF protein pore with two constrictions improved single-read accuracy by 25 to 70% in homopolymers up to 9 nucleotides long.

A dual-constriction biological nanopore resolves homonucleotide sequences with high fidelity.,Van der Verren SE, Van Gerven N, Jonckheere W, Hambley R, Singh P, Kilgour J, Jordan M, Wallace EJ, Jayasinghe L, Remaut H Nat Biotechnol. 2020 Jul 6. pii: 10.1038/s41587-020-0570-8. doi:, 10.1038/s41587-020-0570-8. PMID:32632300^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.