Crystallization and preliminary X-ray study of TsiV3 fromVibrio cholerae

Abstract

The bacterial type VI secretion system (T6SS), a dynamic organelle, participates in microbial competition by transporting toxic effector molecules to neighbouring cells to kill competitors. TsiV3, a recently defined T6SS immunity protein in Vibrio cholerae, possesses self-protection against killing by T6SS predatory cells by directly binding to and inhibiting their effector protein VgrG-3. Structural information about TsiV3 could help to illuminate its specific mechanism. In this study, TsiV3 from V. cholerae was cloned, expressed and crystallized and single-crystal X-ray diffraction data sets were collected to a resolution of 2.55 Å . Specifically, the crystal belonged to space group P2 1 2 1 2 1 , with unit-cell parameters a = 73.3, b = 78.12, c = 106.18 Å . Matthews coefficient calculations indicated that the crystal may contain six TsiV3 molecules in one asymmetric unit, with a V M value of 2.25 Å 3 Da À1 and a solvent content of 45.42%.

Sequential displacement of Type VI Secretion System effector genes leads to evolution of diverse immunity gene arrays in Vibrio cholerae

“…All investigated strains possess the same three clusters structure as previously described for V. cholerae 12 ( Figs 1 and 2 ): one large cluster and two auxiliary clusters (here termed aux-1 and aux-2). The large cluster includes 17 (or 18, depending on the presence of the regulator protein VCA0122 10 ) structural genes that encode proteins forming the membrane-spanning machinery of the T6SS, which also contains the vgrG -3 gene and an immunity gene encoding a protein protecting against the antibacterial activity of the VgrG-3 C-terminus 15 33 . The aux-1 and aux-2 clusters share a common structure: an allele encoding the secreted Hcp protein, a VgrG protein (VgrG-1 and VgrG-2 in aux-1 and aux-2, respectively) followed by an adaptor protein, an additional effector and a cognate immunity protein 17 ( Fig.…”

Sodium dodecyl sulfate-decorated MOF-derived porous Fe2O3 nanoparticles: High performance, recyclable photocatalysts for fuel denitrification

“…Currently, researchers have been focused their attention on using photocatalysts for one-pot removal of NCCs [5][6][7]. While α-Fe2O3 presents a narrow band gap (2.3 eV) and is a promising photocatalyst [8,9], its low photocatalytic efficiency, which is caused by the high photogenerated carrier recombination rate and low surface-to-volume ratio, limits its practical applications.…”

Structural basis for recognition of the type VI spike protein VgrG3 by a cognate immunity protein

“…The supernatant was purified by nickel affinity chromatography. The expression and purification of TsaB (amino acids 27-122) were performed as described previously [23]. The elution of VgrG3C was concentrated and directly applied to gel filtration (Superdex™ 200 10/300 GL, GE Healthcare).…”

“…The selenomethionine (Se-Met) complex was purified and crystallized essentially in the same conditions as native complex. The crystallization of TsaB was performed as described previously [23]. The X-ray diffraction data were collected at beamline 3W1A of Beijing Synchrotron Radiation Facility (BSRF), China.…”