Journal: Journal of the American Chemical Society

Article Title: Probing Bioelectronic Connections using Streptavidin Molecules with Modified Valency

doi: 10.1021/jacs.1c05569

Figure Lengend Snippet: Streptavidin with a controlled ratio of live and dead units. (a) locations of the four biotins bound in the WT tetramer. Thick arrows mark the directions of the biotin connections (from RSC PDB 1STP - note that in this 2D projection, the lengths of the thin arrows marked with dimensions do not reflect true distances). The thio-biotin used in the present work is shown below. (b) Structure showing the subunits in different colors – the approximate locations of the hexaglutamate tails in the SAe4 molecule are shown by the red lines labeled E6. (c) Schematic of the electrochemical STM. Vb is the tip-substrate bias, Vr is the reference bias. (d) Compositions of the reconstituted tetramers. Red = dead monomers, blue = live monomers, arrows = biotin tails, red lines = E6 tails.

Article Snippet: Expression plasmids for hexaglutamate tagged Streptavidin (SAe) and Dead Streptavidin (D) were purchased through Addgene (plasmid #46367 & plasmid #20859).

Techniques: Labeling

Journal: Journal of the American Chemical Society

Article Title: Probing Bioelectronic Connections using Streptavidin Molecules with Modified Valency

doi: 10.1021/jacs.1c05569

Figure Lengend Snippet: Measured distributions of conductance for (a) SAe1D1 (b) SAe2D2 1,2 and 1,4 mixture (c) SAe2D2 1,3 (d) SAe3D1 (e) SAe4 and (f) wild type streptavidin. Gray spots are from sweeping positive to negative, brown spots are from sweeping negative to positive. Colored curves are Gaussian fits to log of conductance. Black curves show the sum of the Gaussians.

Article Snippet: Expression plasmids for hexaglutamate tagged Streptavidin (SAe) and Dead Streptavidin (D) were purchased through Addgene (plasmid #46367 & plasmid #20859).

Techniques:

Journal: Journal of the American Chemical Society

Article Title: Probing Bioelectronic Connections using Streptavidin Molecules with Modified Valency

doi: 10.1021/jacs.1c05569

Figure Lengend Snippet: Rest potential and peak conductance values for the streptavidin molecules. Error bars in the conductance maxima are standard deviation (SD) in the fitted value of the Gaussian peaks for three repeats of the experiments. Error bars in rest potential values are SD of three repeated measurements. NHE is Normal Hydrogen Electrode.

Article Snippet: Expression plasmids for hexaglutamate tagged Streptavidin (SAe) and Dead Streptavidin (D) were purchased through Addgene (plasmid #46367 & plasmid #20859).

Techniques: Standard Deviation

Journal: Journal of the American Chemical Society

Article Title: Probing Bioelectronic Connections using Streptavidin Molecules with Modified Valency

doi: 10.1021/jacs.1c05569

Figure Lengend Snippet: Conductance of the various tetramer compositions as a function of measured surface potential for – blue triangles, Peak III, red dots, Peak II and black squares, Peak 1. The lines are the Lorentzian curves fitted to data for WT streptavidin taken as a function of potential as reported in ref. 7. The conductance of the mutants (data points) fits these curves with no adjustable parameters when plotted vs. their measured rest potentials on the same reference scale.

Article Snippet: Expression plasmids for hexaglutamate tagged Streptavidin (SAe) and Dead Streptavidin (D) were purchased through Addgene (plasmid #46367 & plasmid #20859).

Techniques:

Journal: Journal of the American Chemical Society

Article Title: Probing Bioelectronic Connections using Streptavidin Molecules with Modified Valency

doi: 10.1021/jacs.1c05569

Figure Lengend Snippet: Conductance distributions measured for streptavidin functionalized electrodes bridged by a doubly-biotinylated Φ29 polymerase with (a) WT streptavidin (b) the SAe2D2 1,3 tetramer and (c) the SAe4 tetramer. The cartoon representations are a guide to the gap composition only. The actual structures are likely more compact.

Article Snippet: Expression plasmids for hexaglutamate tagged Streptavidin (SAe) and Dead Streptavidin (D) were purchased through Addgene (plasmid #46367 & plasmid #20859).

Techniques: