Bioanalytical laboratory II (proteomics)

BIOCentre’s Bioanalytical laboratory II (proteomics) provides full package of services: from a single protein characterisation to complex proteomic studies (targeted and non-targeted protein analyses). Additionally, Bioanalytical laboratory II (proteomics) provides analysis of higher order protein structure. 


PROTEIN CHARACTERIZATION

Peptide mapping 
Protein mass mapping involves protein molecule fragmenting using specific enzyme and analysing the resulting peptide mixture by mass spectrometry (MS). Analyses can be direct MS measuring or on-line connected to liquid chromatography (LC-MS). Peptide mass mapping can be extended to protein database search for sequence confirmation. Additionally, peptide mass mapping can also be extended to de novo sequencing.

Molecular weight analysis
The intact molecular weight MS techniques offer accuracy of measurement over a wide molecular weight range. Direct matrix assisted laser desorption ionization mass spectrometry (MALDI-MS) is used for single protein analysis, and liquid chromatography with MALDI-MS detection is used for complex mixtures. 
 
Gel electrophoresis
Gel electrophoresis service offers you measuring of molecular weight and characterizing impurities in biopharmaceutical products. We also offer the study of cellular protein expression by a combination of isoelectric focusing and SDS-PAGE analysis (2-DE). Additionally, gel electrophoresis can be extended to protein identification through in-gel digestion, tandem MALDI-MS analysis (MS/MS) and database search or with Western blot analysis. 
 
Liquid chromatographic patterns
BIOCentre offers a wide range of LC techniques for protein/peptide analysis: Size Exclusion Chromatography (SEC), Reverse-Phase Liquid Chromatography (RP-HPLC) and Ion Exchange Chromatography (IEX).  Additionally, after LC separation we offer MS analysis.
 
Protein sequencing
Protein sequencing service offers MALDI top down sequencing (MALDI-TDS) and de novo sequencing. MALDI-TDS provides protein identification through database search and the simultaneous assignment of the N- and C-termini of up to 70 residues from either terminus. De novo sequencing is used for identification of unknown proteins. It is the process by which the amino acid sequence is deduced without prior knowledge of the DNA or protein sequence. Biocenter’s de novo sequencing service reveals structural information by laser induced fragmentation within a mass spectrometer (LIFT). 

 
PROTEOMICS ANALYSIS

Gel electrophoresis
Gel electrophoresis services include 1-DE or 2-DE SDS-PAGE protein separation and visualization followed by densitometric analysis and relative protein quantification. Additionally, gel electrophoresis can be extended to protein identification through in-gel digestion, MALDI-MS/MS analysis and protein database search or with Western blot analysis. 
 
Liquid chromatography with tandem mass spectrometry detection (LC-MS/MS) 
LC-MS/MS services provide target and non-target proteome analysis

Non-target proteomics or “shotgun” proteomics service generally involves in-solution protein digestion using a suitable enzyme. Resulting peptides are separated by nano-LC and peptide fraction are collected. Separated peptides are analysed by MALDI-MS/MS and identified by protein database search. Non-target proteomics is focused on the cataloguing of proteins (from cells or tissues) or for determination of changes in protein expression between samples.

Targeted proteomic service targets specific peptides in a complex mixture and determines their presence. This analysis usually utilizes a triple quadrupole mass spectrometer (QQQ). Targeted proteomics is usually used for verification of knockdown targets, for quantification of a peptide/protein in a complex mixture and for a specific protein monitoring across samples or during a time course experiment.
 

HIGHER ORDER PROTEIN STRUCTURE

Circular dichroism (CD) 
Circular dichroism enables spectroscopic analysis for protein secondary structure assessment (alpha helix/beta sheets). 

Differential scanning calorimetry (DSC)
Differential scanning calorimetry can be used for protein thermodynamic parameters measurements (e.g. melting point determination) to screen protein stability.