UNIVERSITY OF MICHIGAN MEDICAL SCHOOL

BRCF Home Biosafety Containment Biochemical Nuclear Magnetic Resonance Biomedical Research Store DNA Sequencing Flow Cytometry Protein Structure Facility Peptide Synthesis Protein Analysis Protein Mass Spectrometry Request Forms Service Fees Policy Facility Personnel Instrumentation Contact Us Transgenic Animal Model Other Resources

Administrative Office
2570 MSRB II
1150 West Medical Center Drive
University of Michigan
Ann Arbor, MI 48109-0674
734 647 4776
734 936 2622 fax

Protein Structure Facility: Policy

General

Information on Request Forms
Request forms must be filled out completely and truthfully. Request forms submitted incompletely will be delayed.

Outsourcing of Requests
In case of lack of instrumentation (e.g. for Amino Acid Analysis) or insufficient instrument capacity, the Protein Structure Facility will suggest to outsource the request to a reliable academic or commercial source. The client is responsible for the outside laboratories quoted fee and the usual discounts apply for center members. The outside laboratories turn around times apply. The Protein Structure Facility performs quality control and data review respectively prior to providing results obtained for an outsourced project. The Protein Structure Facility is not responsible for turn around times and pricing provided by the outside laboratory.

Protein Analysis and Mass Spectrometry

It is the client’s responsibility to ensure correct sample preparation according to PSF sample preparation guidelines. The sample container must be clearly labeled and the label must match the sample name on the request form. Correct sample preparation is critical for all protein analysis, e.g. for samples submitted for in gel digestion and subsequent mass spectrometry analysis. If the desired result is not obtained due to the nature of the sample submitted, fees still apply in full.

Turn around times

MALDI-MS (molecular weight determination):	2-5 business days
In-gel digestion and Peptide mass mapping:	5-7 business days
Data base searches:	additional 1-2 business days
Extensive data interpretation:	additional 2-5 business days
LC-MS/MS analysis:	3-5 business days
Protein Identification by LC-MS/MS:	10 business days

*Turn around times mainly depend on the operational state of our protein sequencer and may exceed the printed time frame in case of instrument downtime.

Peptide Synthesis

Turn Around Times

Non-purified crude peptides:	7-10 business days
Purified routine peptides:	2-4 weeks
Purified non-routine peptides	4-6 weeks

Turn around times for some labeled peptides, cyclic peptides and peptides carrying Post-translational modifications may be longer (up to 8 weeks) depending on the nature of the peptide sequence or project.

Yield and Purity
PSF guarantees yield “brackets” for non-purified peptides (crude) and purified peptides depending on the synthesis scale as printed on the request form. Please provide the desired yield and purity for the application of the peptides on the request form. If no specifications are provided, the facility will purify to reach 85%-95% purity and prioritize purity over yield.

Synthesis Scale	Non-Purified Peptides (Crude)	Purified Peptides
Small scale	5-40 mg	1 -5mg
Half scale	20-60 mg	2-10 mg
Medium Scale	40-120 mg	4 -15 mg
Full scale	100 mg –300 mg	10mg –30 mg
Large Scale	250mg-600mg	25 mg –60 mg

The obtainable yield for purified peptides depends on the initial purity of each individual peptide. The yield obtained after purification may be higher than the guaranteed minimum yield depending on the peptide length, sequence and initial purity obtained after synthesis. The less purity requested, the higher the yield that can be obtained. The higher the requested purity, the lower the yield obtained. Yields obtained may vary from yields requested by 35% due to differences in the peptide content (mg peptide per mg solid). The peptide content obtained is in general 45%-80% and depends on the nature of the peptide (e.g. net, charge, counter ions and water retained) and the vacuum of the final freeze-drying step. For the same reason yields for repetitive requests of the same peptide and synthesis scale may vary by up to 35%.

Non-routine Synthesis Requests
Turn Around times for non-routine synthesis requests (e.g. cyclic peptides) may exceed the above listed time frame. Status updates will be provided on a weekly basis after the 4 -6 weeks. A specialized quotation may be issued for a non-routine synthesis request if an unusual procedure or specialized reagents are needed. Quotations are based on PSF approved service fees but for special procedures may supersede the general pricing.

Facility Acknowledgement in Publications (required for Center Members)

When research that utilizes synthetic peptide or protein data obtained from the Protein Structure Facility is published, the facility should be acknowledged in the publication. For example: “Synthetic peptides were provided by The University of Michigan Protein Structure Facility (Dr. Henriette Remmer, director)”.

The facility provides summaries of the methods used for peptide synthesis or protein analysis for publication purposes upon request (email: hremmer@umich.edu). In addition, center members need to provide a copy of the publication or the literature citation to the facility. The facility needs this information for federal grant reporting. Lack of this information lowers the facility’s rating in federal grants.