@article {2014|1645,
	title = {Type VI secretion and bacteriophage tail tubes share a common assembly pathway.},
	journal = {Embo Rep.},
	volume = {15},
	year = {2014},
	month = {mar},
	pages = {315{\textendash}21},
	abstract = {<p>The Type VI secretion system (T6SS) is a widespread macromolecular structure that delivers protein effectors to both eukaryotic and prokaryotic recipient cells. The current model describes the T6SS as an inverted phage tail composed of a sheath-like structure wrapped around a tube assembled by stacked Hcp hexamers. Although recent progress has been made to understand T6SS sheath assembly and dynamics, there is no evidence that Hcp forms tubes in vivo. Here we show that Hcp interacts with TssB, a component of the T6SS sheath. Using a cysteine substitution approach, we demonstrate that Hcp hexamers assemble tubes in an ordered manner with a head-to-tail stacking that are used as a scaffold for polymerization of the TssB/C sheath-like structure. Finally, we show that VgrG but not TssB/C controls the proper assembly of the Hcp tubular structure. These results highlight the conservation in the assembly mechanisms between the T6SS and the bacteriophage tail tube/sheath.</p>},
	keywords = {Amino Acid Sequence, Bacterial Secretion Systems, Escherichia coli, Escherichia coli Proteins, Molecular Sequence Data, Protein Binding, Protein Multimerization, Protein Structure, Tertiary, Virulence Factors},
	issn = {1469-3178},
	doi = {10.1002/embr.201337936},
	author = {Brunet, Yannick R and J{\'e}r{\^o}me H{\'e}nin and Celia, Herv{\'e} and Cascales, Eric}
}
@article {2008|1603,
	title = {Diffusion of glycerol through Escherichia coli aquaglyceroporin GlpF},
	journal = {Biophys. J.},
	volume = {94},
	number = {3},
	year = {2008},
	pages = {832{\textendash}839},
	abstract = {The glycerol uptake facilitator, GlpF, a major intrinsic protein found in Escherichia coli, selectively conducts water and glycerol across the inner membrane. The free energy landscape characterizing the assisted transport of glycerol by this homotetrameric aquaglyceroporin has been explored by means of equilibrium molecular dynamics over a timescale spanning 0.12 micros. To overcome the free energy barriers of the conduction pathway, an adaptive biasing force is applied to the glycerol molecule confined in each of the four channels. The results illuminate the critical role played by intramolecular relaxation on the diffusion properties of the permeant. These free energy calculations reveal that glycerol tumbles and isomerizes on a timescale comparable to that spanned by its adaptive-biasing-force-assisted conduction in GlpF. As a result, reorientation and conformational equilibrium of glycerol in GlpF constitute a bottleneck in the molecular simulations of the permeation event. A profile characterizing the position-dependent diffusion of the permeant has been determined, allowing reaction rate theory to be applied for investigating conduction kinetics based on the measured free energy landscape.},
	keywords = {Aquaporins, Chemical, Computer Simulation, Diffusion, Escherichia coli Proteins, Glycerol, Ion Channel Gating, Models, Molecular, Molecular Conformation, Porosity},
	doi = {10.1529/biophysj.107.115105},
	author = {J{\'e}r{\^o}me H{\'e}nin and Emad Tajkhorshid and Klaus Schulten and Christophe Chipot}
}
