Designed for use with the Crystal Former, the SuperCOMBI screen offers efficient crystallization screening for liquid-liquid diffusion without the redundancy present in sparse matrix screens designed for vapor diffusion methods.

 

Features:

 


  • 96 individual crystallization conditions
  • Comprised of both MCSG and PurePEG screens.
  • Efficient, non-redundant conditions designed to maximize the potential of capillary crystallization
  • Available as deep-well block format with 1mL per condition

 

Rationale

The SuperCOMBI has been design to maximize crystallization returns in the Crystal Former by creating a minimum set of conditions that, when coupled with the gradients sampled in the microcapillaries of the Crystal Former, provide broad and complete coverage of crysatllization space. The first 48 conditions derive from the MCSG crysatllization suite to provide high productivity in a pared down set of starting conditions. These conditions are among the most productive of those commercially available. Conditions 49-96 derive from the PurePEGs screen for which the Crystal Former is able to generate a complex PEG gradient to sample this commonly-successful region of crystallization space in an efficient and cost-effective manner. 

 

Why diffusive mixing?

Diffusive mixing offers tremendous advantages in protein crystallization, including the ability to assess protein phase behavior across the gradient of a given condition for each microchannel used. In contrast to vapor diffusion, exploration of crystallization space becomes more systematic and complete in this format. 

 

What's included?

The Crystal Former can be readily automated on standard liquid handling robots for both protein and reagent dispenses. We have opted to include a 96-well Greiner source plate for customers wishing to use Mosquito (TTP LabTech) or NT8 (Formluatrix) to dispense the SuperCOMBI screen into the Crystal Formers. Users with systems from Art Robbins Instruments can source directly from the provided deep well block. For more information on appropriate protocols for automated Crystal Former set-up, please contact our support team.

SuperCOMBI
SKU
SSC-1

0.1 M sodium chloride, 0.1 M Bis-Tris:HCl 6.5, 1.5 M Ammonium Sulfate
SSC-1 $83.00
SSC-10

0.1 M Na2HPO4:Citric acid pH 4.2, 40% (v/v) PEG 300
SSC-10 $83.00
SSC-11

0.2 M calcium acetate hydrate, 0.1 M sodium cacodylate:HCl pH 6.5, 0.4 PEG 300
SSC-11 $83.00
SSC-12

0.2 M ammonium sulfate, 0.1 M Bis-Tris:HCl pH 5.5, 25% (w/v) PEG 3350
SSC-12 $83.00
SSC-13

0.2 M magnesium chloride, 0.1 M HEPES:NaOH pH 7.5, 25% (w/v) PEG 3350
SSC-13 $83.00
SSC-14

0.2 M sodium chloride, 0.1 M Bis-Tris:HCl pH 5.5, 25% (w/v) PEG 3350
SSC-14 $83.00
SSC-15

0.2 M ammonium acetate, 0.1 M Bis-Tris:HCl pH 5.5, 25% (w/v) PEG 3350
SSC-15 $83.00
SSC-16

0.2 M magnesium chloride, 0.1 M Bis-Tris:HCl pH 6.5, 25% (w/v) PEG 3350
SSC-16 $83.00
SSC-17

0.2 M magnesium chloride, 0.1 M Tris:HCl pH 8.5, 25% (w/v) PEG 3350
SSC-17 $83.00
SSC-18

0.2 M sodium thiocyanate pH 6.9, 20% (w/v) PEG 3350
SSC-18 $83.00
SSC-19

0.2 M potassium thiocyanate, 20% (w/v) PEG 3350
SSC-19 $83.00
SSC-2

0.2 M ammonium phosphate monobasic, 0.1M Tris:HCl pH 8.5, 50% (v/v) MPD
SSC-2 $83.00
SSC-20

0.2 M potassium sodium tartrate, 20% (w/v) PEG 3350
SSC-20 $83.00
SSC-21

0.1 M Tris:HCl pH 8.5, 25% (w/v) PEG 3350
SSC-21 $83.00
SSC-22

0.2 M potassium iodide, 20% (w/v) PEG 3350
SSC-22 $83.00
MCSG1-2 A2 2 MCSG-1 100mL $83.00
MCSG1-20 B8 20 MCSG-1 100mL $83.00
MCSG1-21 B9 21 MCSG-1 100mL $83.00
MCSG1-22 B10 22 MCSG-1 100mL $83.00
MCSG1-23 B11 23 MCSG-1 100mL $83.00
MCSG1-24 B12 24 MCSG-1 100mL $83.00
MCSG1-25 C1 25 MCSG-1 100mL $83.00
MCSG1-26 C2 26 MCSG-1 100mL $83.00
MCSG1-27 C3 27 MCSG-1 100mL $83.00

How was the MCSG screen developed?

The MCSG Crystallization Suite has been developed by the Midwest Center for Structural Genomics for use throughout the PSI:Biology initiative. The component crystallization conditions of the Suite have been mined from over a dozen of commercially available screens throughout 10 years of extensive crystallization trials carried out through previous phases of the PSI. Only conditions giving crystal hits were included in the screen, resulting in the most validated, chemically diverse and non-redundant screen on the market today.

What target type of targets is MCSG screen suitable for?

Over 40,000 targets from more than a 100 different organisms, both prokatyotic and eukaryotic, including bacteria, C. elegans, S. cerevisiae, humans and mice were used for data mining of the screen. The broadest target base of MCSG likely produced conditions that are more applicable to a larger number of protein families and organisms than any other sparse matrix screen on the market.

How is the screen organized?

The complete MCSG suite comprises 384 conditions. Conditions 1-288 are organized in order of decreasing crystal productivity in screens MCSG-1, MCSG-2 and MCSG-3. Thus MCSG-1 condition A1 has yielded the greatest number of unique crystals for all targets screened with the suite predecessors. The conditions that comprise MCSG-4 have been rationally selected to systematically sample regions of crystallization space for proteins requiring additional screening. They were selected from a set of conditions for crystallizing difficult proteins, with all conditions giving crystals.

I have a challenging target with not enough protein to run all four MCSG screens. Which of the MCSG screens should I chose to maximize the crystallization potential?

While the first three screens are arranged in order of productivity, MCSG 4 set was mined from singleton hit conditions of fewer difficult targets, and contains a more unique set of precipitants combinations. Therefore, running MCSG 1 and 2 would cover most productive conditions. Given enough protein, addition of MCSG4 will provide additional coverage of crystallization space.

Our lab stocks a variety of screens from multiple manufacturers, why should we consider adding yet another screen to our inventory?

With numerous crystallization screens available, it can be difficult to ensure that purchased screens do not overlap significantly with one another, sampling the same or very similar conditions multiple times. Setting up numerous screens for each sample is also costly in terms of consumption of precious protein, materials and time. Moreover, multiple survey studies indicate that 200-400 of well-selected conditions are sufficient to assess crystallizability of a protein sample. MCSG screen allows to streamline the screening process by covering the most chemical space in the least number of well-selected and validated conditions. Multiple structural genomics centers and industrial groups have adopted MCSG screen as the only initial screen, and are getting excellent result with it. For success stories please click here.

We use JCSG + or JCSG Core suite in our lab as a first screening pass, how is MCSG different?

The JCSG+ screen was mined from a limited set of Thermotoga maritima proteins, while JCSG Core suite was validated on a more diverse set of mostly bacterial targets. In contracst, MCSG was validated on the largest and most diverse set of organisms of any screen: over 40,000 tragets from over 100 prokatyotic and eukaryotic organisms. Therefore, MCSG conditions are more likely to be applicable to crystallization of increasingly more challenging targets from diverse organisms. Furthermore, MCSG screen was mined from a larger sampling of commercially available screens, ensuring greater coverage of crystallization space, and contains a wider variety of chemicals than JCSG screen. MCSG screen is chemically dissimilar to the JCSG screen based on the C6 analysis. While most conditions of the “core 67” JCSG+ set (conditions deemed critical for protein crystallization) were also found in the MCSG suite in identical or modified form, only 13 of these fell into the most productive MCSG1 set, meaning that MCSG1 contains a multitude of more productive conditions than JCSG+.

How chemically similar is MCSG to other sparse matrix screens on the market?

The analysis of MCSG screens using C6 server (http://c6.csiro.au/) revealed that overall the MCSG suite conditions are significantly different from the compositions of other commercial screens. MCSG4 is the only MCSG screen to exhibit significant overlap with another commercial screen, PEGsII suite from Qiagen. This is not surprising, given the consistent sampling of polyethylene glycols employed in the rationally designed MCS4 suite. However, given that the MCSG4 screen has been assembled to specifically complement the MCSG1-3 screens, we recommend its use as part of the MCSG paradigm to ensure that the subtleties of the full suite are not missed. In addition, MCSG suite exhibits an internal chemical diversity on par with other sparse matrix screens on the market.

What formats does the MCSG screen come in?

MCSG screen is available in the2 mL deep well block format with 1.7 mL of each condition. The blocks are heat-sealed for safer transportation and longer storage. The tube format consists of 15 mL comical tubes containing 10 mL of screening solutions. The tubes racks are shrink-wrapped for safer transportation.

How does the cost of MCSG screen compare to other screens on the market?

We provide the most competitive pricing of the screens in deep well block format due to the higher volume of solutions in each well (1.7 mL compared to 1.0 or 1.5 mL for most other manufacturers). Our tube format is competitively priced compared to most other manufacturers. MCSG can provide significant cost savings be virtue of being a very economical screen on per mL basis, and in addition it can be used to streamline your initial screening pipeline from multiple screens to just four.

Do you have production reports available?

Yes, Lot-specific production reports are available for the MCSG screen. Simply provide the Lot # from your block or tube set to support@microlytic.com and you will receive a detailed production report including the lots of the individual chemicals used within 24-48 hours.

Can I buy optimization reagents for the MCSG screen?

MCSG condition refills are available in 100 mL volumes. We also offer all individual component chemicals as liquid or dry stocks. These reagents are same high purity grade used in the MCSG screen manufacturing.