Experiments were performed at 9.4 and 34 GHz using Bruker ElexSys 580 and 680 spectrometers. For T2 determination we used a simple 2-pulse sequence, invoking a first π/2 pulse of 16 ns, and an initial delay of the second pulse of 300 ns. The resulting echo was integrated over 175 ns. For T1, a 3-pulse sequence was used. An initial π pulse of 32 ns was followed after 300 ns delay by a 2-pulse echo sequence with 200 ns initial pulse delay for monitoring the inversion recovery. For Rabi experiments, a single π/2 pulse was used. Its length was incremented by 2 or 4 ns. After a delay of ∼84 ns with respect to the pulse ending, the signal was observed with a short integrating time of 16 ns.
Elexsys 580
Manufactured by Bruker
The Elexsys 580 is a state-of-the-art electron paramagnetic resonance (EPR) spectrometer developed by Bruker. It is designed to provide high-performance and versatile capabilities for advanced EPR spectroscopy. The Elexsys 580 offers a range of features and functionalities to support a wide variety of EPR applications, including materials science, chemistry, and biology research.
Automatically generated - may contain errors
8 protocols using elexsys 580
1
EPR Spectroscopy Pulse Sequence Methods
2
Spin-Labeled GlpG Membrane Protein Analysis
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
The final concentration of spin-labeled GlpG in DDM, bicelles, or liposomes was 50 to 100 μM. Four-pulse DEER data were collected on a Q-band Bruker ELEXSYS 580 spectrometer using a 150-W amplifier and an E5106400 cavity resonator (Bruker Biospin). Samples were loaded into quartz capillaries and flash frozen in liquid nitrogen prior to data collection at 50 K. The interspin distances were determined from fits to the background-corrected dipolar evolution data using the model-free, nonnegative Tikhonov regularization algorithm on the LongDistances program (http://www.biochemistry.ucla.edu/Faculty/Hubbell/ ).
3
Pulsed EPR Measurements of GlpG Enzyme
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
DEER-EPR measurements were performed on a Bruker Elexsys 580 spectrometer with Super Q-FTu Bridge, Bruker ER 5107DQ resonator and 10 W Q-band amplifier at 80 K. The spin-labeled samples ranging from 80 to 160 μM GlpG were flash-frozen in quartz capillaries using a liquid nitrogen bath immediately prior to data collection. For data collection, 36-ns π-pump pulse was applied to the low field peak of the nitroxide absorption spectrum, and the observer π/2 (16 ns) and π (32 ns) pulses were positioned 17.8 G (50 MHz) upfield, which corresponded to the nitroxide center resonance. A two-step phase cycling (+x, −x) was carried out on the first (π/2) pulse from the observer frequency. The time domain signal collected for each sample varied from 2.3 to 2.5 μs. Based on the collection time, the reliable inter-spin distance range was ~15−~60 Å. DEER data were analyzed using the program LongDistances, which was written in LabVIEW by Christian Altenbach (http://www.biochemistry.ucla.edu/biochem/Faculty/Hubbell/ ).
4
DEER Spectroscopy for Nanoscale Protein Structure
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
For DEER measurements, deuterated glycerol was added to the samples as a cryo-protectant (final concentration 20%). Spin-labeled GR-67R1 was loaded into quartz capillaries (1.5 mm ID and 1.8 mm OD) and flash frozen using a dry ice/ethanol bath. After freezing, the capillaries were loaded into an ER 5107D2 Q-band flexline resonator and Q-band measurements were performed at 80 K on a Bruker Elexsys 580 spectrometer with a Super Q-FTu Bridge. A 32-ns π-pump pulse was applied to the low field peak of the nitroxide field swept spectrum, and the observer π/2 (16 ns) and π (32 ns) pulses were positioned 50 MHz (17.8 G) upfield, which corresponds to the nitroxide center line. Distance distributions were obtained from the raw data using the LabVIEW (National Instruments) program “LongDistances” [developed by Christian Altenbach and Wayne Hubbell, University of California, Los Angeles (UCLA)] that can be downloaded from http://www.biochemistry.ucla.edu/biochem/Faculty/Hubbell/ . The DEER distance peak simulations were conducted with the open-source package Multiscale Modeling of Macromolecules (MMM)63 (link).
5
Organic Thin-Film Preparation and ESR Analysis
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
Films were prepared under inert
atmosphere by drop-casting 20 μL of solution (concentration
of 5 g/L) onto synthetic quartz glass substrates (Ilmasil PS, QSIL
GmbH) with dimensions of 3 × 25 mm2, followed by annealing
at 150 °C for 120 min after films were dried completely. The
annealed films were placed into synthetic quartz glass tubes (Ilmasil
PS, QSIL GmbH) with 3.8 mm outer and 3.0 mm inner diameters and the
tubes sealed afterward. ESR spectra were recorded at room temperature
on an Elexsys 580 (Bruker Biospin GmbH) spectrometer equipped with
a 4119HS-W1 (Bruker) cavity: microwave frequency, 9.800 GHz; microwave
power, 150 μW (30 dB attenuation, 150 mW source power); modulation
frequency, 100 MHz; modulation amplitude, 0.1 mT.
atmosphere by drop-casting 20 μL of solution (concentration
of 5 g/L) onto synthetic quartz glass substrates (Ilmasil PS, QSIL
GmbH) with dimensions of 3 × 25 mm2, followed by annealing
at 150 °C for 120 min after films were dried completely. The
annealed films were placed into synthetic quartz glass tubes (Ilmasil
PS, QSIL GmbH) with 3.8 mm outer and 3.0 mm inner diameters and the
tubes sealed afterward. ESR spectra were recorded at room temperature
on an Elexsys 580 (Bruker Biospin GmbH) spectrometer equipped with
a 4119HS-W1 (Bruker) cavity: microwave frequency, 9.800 GHz; microwave
power, 150 μW (30 dB attenuation, 150 mW source power); modulation
frequency, 100 MHz; modulation amplitude, 0.1 mT.
6
CW-ESR Spectroscopy of Glycerol-Containing Samples
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
For the CW-ESR measurement, ∼200 μL of the sample, which contained 20% glycerol, was transferred into a 4-mm EPR quartz tube. The CW-ESR spectra were recorded in a Bruker ELEXSYS 580, equipped with an X-band microwave bridge and ER 4122 SHQE resonator, and an ER 4131 VT unit for temperature control. The spectra were recorded at 200 K with a microwave frequency of ∼9.43 GHz, microwave power of 1.5 mW, modulation frequency of 100 kHz, modulation amplitude of 1 G, and scan width of 200 G and 1,024 data points.
7
EPR Spectroscopy of Protein Samples
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
EPR spectra were
recorded at room
temperature on a Bruker ELEXSYS 580 instrument using the High Sensitivity
Resonator (Bruker). Each spectrum is the average of 25 scans of 30
s each over a range of 100 G. Samples (6 μL) at protein concentrations
of 50–100 μM were placed in 0.6 (inside diameter) ×
0.84 (outside diameter) borosilicate capillary tubes. All samples
were in 5 mM MES [2-(morpholino)ethanesulfonic acid] buffer with DM
concentrations varying from 3 to 5%.
recorded at room
temperature on a Bruker ELEXSYS 580 instrument using the High Sensitivity
Resonator (Bruker). Each spectrum is the average of 25 scans of 30
s each over a range of 100 G. Samples (6 μL) at protein concentrations
of 50–100 μM were placed in 0.6 (inside diameter) ×
0.84 (outside diameter) borosilicate capillary tubes. All samples
were in 5 mM MES [2-(morpholino)ethanesulfonic acid] buffer with DM
concentrations varying from 3 to 5%.
8
Pulsed EPR Measurements of GlpG Enzyme
About PubCompare
Our mission is to provide scientists with the largest repository of trustworthy protocols and intelligent analytical tools, thereby offering them extensive information to design robust protocols aimed at minimizing the risk of failures.
We believe that the most crucial aspect is to grant scientists access to a wide range of reliable sources and new useful tools that surpass human capabilities.
However, we trust in allowing scientists to determine how to construct their own protocols based on this information, as they are the experts in their field.
Ready to get started?
Sign up for free.
Registration takes 20 seconds.
Available from any computer
No download required
Revolutionizing how scientists
search and build protocols!