Molecular Model of a Type III Secretion System Needle

Molecular model of a type III secretion system needle: Implications for host-cell sensing.

Helical Structure of the Needle of the Type III Secretion System of Shigella Flexneri

METHOD--RECIPROCAL SPACE FIT REFINEMENT PROTOCOL--X-RAY

A SET OF X-RAY STRUCTURE FACTORS WERE COMPUTED BY PLACING THE EM DENSITY IN A CRYSTAL CELL. THE MXIH MONOMER WAS RIGID BODY REFINED AGAINST THESE DATA WITH HARD NCS CONSTRAINTS. THE EM DENSITY FOR THE NEEDLE WAS PUT IN THIS P1 CRYSTAL CELL SO THAT SINGLE CRYSTAL X-RAY MODEL REFINEMENT PROGRAMS COULD BE USED TO FIT THE MODEL.

STAINED WITH A DROP OF 2% URANYL ACETATE, PH 7.5
SHIGELLA FLEXNERI TYPE THREE SECRETION NEEDLE

RESIDUES 2-19 WERE MODELLED AS AN ALPHA HELIX. RESIDUES 20-80 COME FROM MOLECULE A OF PDB ENTRY 2CA5 RESIDUES 81-85 WERE MODELLED AS AN ALPHA HELIX.

MSVTVPNDDWTLSSLSETFDDGTQTLQGELTLALDKLAKNPSNPQLLAEYQSKLSEYTLYRNAQSNTVKVIKDVDAAIIQ
NFR

MXIH NEEDLE PROTEIN OF SHIGELLA FLEXNERI (MONOMERIC FORM, RESIDUES 1-78)

CA ATOMS ONLY, CHAIN A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y, Z, 1, 0

T3SS, VIRULENCE, TRANSPORT, PROTEIN TRANSPORT