Premium
Stretching the arms of the type VI secretion sheath protein
Author(s) -
Leiman Petr G
Publication year - 2018
Publication title -
embo reports
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 4.584
H-Index - 184
eISSN - 1469-3178
pISSN - 1469-221X
DOI - 10.15252/embr.201745627
Subject(s) - structural biology , secretion , effector , biology , chemistry , microbiology and biotechnology , biochemistry
The bacterial type VI secretion system (T6 SS ) is a multicomponent complex responsible for the translocation of effector proteins into the external milieu. The T6 SS consists of an external sheath, an internal rigid tube, a baseplate, and a T6 SS ‐specific membrane complex. Secretion is accomplished by the contraction of the sheath, which expels the effector‐loaded tube. In this issue of EMBO reports , Brackmann et al [1][Brackmann M, 2017] show how modifications of the sheath subunits can lock the T6 SS assembly in the extended state. These findings allowed Wang et al [2][Wang J, 2017] and Nazarov et al [3][Nazarov S, 2017] to purify the T6 SS sheath–tube–baseplate complex in the extended pre‐secretion state and to analyze its structure using cryo‐electron microscopy (cryo EM ).