The Microchemistry and Proteomics Facility (MPC) supports laboratory and clinical research programs at Memorial Sloan-Kettering by providing synthetic peptides and by carrying out mass spectrometric and amino acid sequence analyses of proteins and peptides, generally for the purpose of identification, relative quantitative analysis and post-translational modification (PTM) analysis. Synthetic molecules are made according to specifications provided by the investigator. Polypeptides submitted for identification (either single proteins or mixtures), PTM analysis or N-terminal sequencing are prepared by the lab requesting service. Information on chemistries and instrumentation, and expert advice on experimental approaches are provided by facility staff when needed.
The Core provides the following services:
Mass Spectrometry-Based Protein Identification, Post Translational Modification Analysis, and Relative Protein Quantification
- Complex protein analysis through 'geLC-MS/MS' protein mixtures (up to 500-1000 proteins or more), received as concentrated gel stacks or resolved gels; micro-digestion and standard processing prior to LC-MS/MS
- Post-translational modification (PTM) analysis (phosphorylation, methylation, acetylation, ubiquitinylation, sumoylation) and quantitative analysis of Seleno-Methionine incorporation
- Simple protein identification (up to ~3 proteins in mixture, 50-200 fmol starting material), micro-digestion (individual gel slices), chemical derivatization, mass fingerprinting, and MS/MS using MALDI-TOF, and MALDI-TOF/TOF Mass Spectrometry
- Label-free relative quantification (e.g., emPAI, Spectral Counts)
- Stable Isotope Labeling of Amino Acids in Cell Culture (SILAC) quantification using MaxQuant and/or Mascot Distiller softwares
N-Terminal Sequencing (Edman Degradation)
- Mapping domains in large proteins: analysis of higher order protein structure, primary structure identification through limited sequence analysis (5-10 cycles); individual fragments are submitted as bound onto PVDF membranes
Custom Synthetic Peptides
- Provide synthesized peptides of up to 50 amino acids in length at yields of approximately 10-20mg (peptides >50 aa and yields exceeding 20mg provided upon special request)
- Modifications: phosphorylation, methylation, acetylation, glycosylation, sulfation, biotinylation, fluorescent dyes, etc.Radiolabeling (at N-terminus only), 15N, 13C-arginines and -glutamines, 14C-glycine and -alanine
- Other peptide services: disulfide-linkage, cyclic peptides, D-stereoisomer incorporation, etc
Mass Spectrometry Analysis of Fragments Prepared by Users
- Polypeptides are analyzed by MALDI-TOF Mass Spectrometry (Sample: Estimated Mr: up to ~20kDa in compatible buffers)
