This Request for Proposal (“RFP”) is an invitation to prospective Proponents to submit Proposals for the provision of an automated crystallization drop setter under humidity controlled environment for the research to understand the molecular regulation of cholesterol and lipid metabolism via ATP-binding cassette (ABC) transporters. ABC transporters are a class of membrane-spanning proteins and use ATP as the primary energy source to carry out metabolite/nutrient translocation across the cell membranes. Using membrane protein structural biology and X-ray crystallography, our research analyze the 3-D protein structure to understand (a) how these membrane proteins facilitate the movement of cholesterol/lipid molecules across the cell membranes, (b) through what mechanisms the ABC transporters translocate lipid molecules across the plasma membranes, and (c) what pharmacological strategies can be devised for cholesterol-controlling medications. The current proposal will acquire a robot that is specifically designed for high-throughput crystal growth of memrbane proteins under high lipid-content conditions.
In order to determine the structure of proteins, X-ray crystallography is used and protein molecules have to be crystallized first. Obtaining the “well-diffracting” protein crystals is one of the most difficult steps of protein crystallography and involves screening and optimization of large number of different crystallization conditions (>1000) as each protein molecules crystallize in different conditions. We are seeking an automated crystallization drop setter to speed up crystallization process in an higher thoughput manner. The instrument should help automatically set up crystallization drops in nanoliter volume under humidity controlled environment, in order to maximize crystallization reproducibility. It should support the setup for all crystallization methods including both vapor diffusion, microseeding, and lipidic cupic phase (LCP).
The Appendix A specifications contained in this RFP are the mandatory minimum requirements for the Humidity-Controlled and Automated Crystallization Drop Settler for Membrane Proteins System.
Minimum Mandatory Requirements:
Drop Setter Instrument
1.1 The instrument must be able to set up hanging and sitting drop protein crystallization experiments
1.2 The instrument must have a full enclosure for operational safety and cleanness
1.3 The instrument must have active humidity control, allowing for humidification levels to be set and maintained by a user during plate setup
1.4 The instrument must be able to automatically transfer screen solutions from deep well block to crystallization plate
1.5 The instrument must support any 96 well commercial SBS plate
1.6 The instrument robot must be able to set up crystallization plates with utilization of the following techniques: sitting drop, hanging drop, microbatch, microseeding
1.7 The instrument must allow two or more plates to be dispensed at once with user defined protocol
1.8 The crystallization setup must not allow for cross contamination
1.9 The instrument must be able to dispense liquid in a volume as small as 50nL with a coefficient of variation (CV) of 5% or better
1.10 The instrument must be able to work with both disposable and washable tips
1.11 The instrument must be able to mix and dispense Lipidic Cubic Phase (LCP) drops for membrane protein crystallization
1.12 The instrument must contain an automated Lipidic Cubic Phase (LCP) mixing station
1.13 The instrument must carry out automatic Lipidic Cubic Phase (LCP) syringe calibration.
1.14 The instrument must be able to dispense an Lipidic Cubic Phase (LCP) drop size of 25nL and up
1.15 The instrument must not leave the Lipidic Cubic Phase (LCP) drops uncovered for more than 10 seconds
Instrument Software
2.1 The instrument must include the controlling software
Installation, Training and Warranty
3.1 The system must include a 1 year standard manufacturer’s warranty.
3.2 The system must include installation and on-site training.
3.3 Proponent must be able to provide extended warranty for a minimum of 4 additional years
