Protein analysis

1. Protein Identification

(1)ProteinID for gel band/spots: Analyzing SDS-PAGE gel bands or 2D spot stained with coomassie, silver, fluorescent dye.

(2)ProteinID for solution samples of the simple protein mixture: Up to 100 different proteins in a solution samples can be reliably identified by our high resolution and ultra-sensitive NanoLC-MS/MS procedure.

(3)Complete profiling of a complex protein mixture: Up to 1000 different proteins in a complex protein mixture can be identified. 

2. Protein Characterization

Detailed analysis of protein structure is of vital importance in the study of protein functions and the development of biologics. Our Protein Characterization services offer in-depth analysis of the primary structure and disulfide bond linkage of purified or expressed proteins.  Our Peptide Mapping service provides a high confident protein sequence conformation with 100% coverage. Our protein N-and C-terminal analysis can identify proteins with multiple or modified N- or C-terminals due to in vivo processing or proteolytic cleavage. Our disulfide bond mapping can analyze both correctly linked disulfide bonds as well mismatched disulfide bonds.

(1)Peptide Mapping

(2)Disulfide Bond Analysis

(3)N-terminal and C-terminal Sequencing

3. Protein Glycosylation and PTM analysis

With cutting edge technology we have developed in analyzing protein glycosylation, a co-translational process, we have served a large number of scientific researchers around the world in the qualitative and quantitative analysis of protein glycosylation, including quantitative released N-glycan analysis, site-specific N- and O-glycosylation analysis, glycan linkage analysis, etc.

Also, we have developed the proprietary technology for analyzing a large range of protein post-translational modifications (PTMs), including Phosphorylation, methylation, acetylation, ubiquitination, SUMOylation, or any of several hundred different types of protein PTMs. We have provided the services to a large number of academic and industrial clients for PTM analysis and many high profile research papers have been published that is related to our service.

4. Proteomics

Proteomic analysis is an essential tool in the discovery of protein biomarkers, which may act as targets for disease diagnostics and therapeutic interventions. Our provides LC-MS based proteomic analysis. Building on our broad range of expertise in protein analysis and protein purification and functional studies, we are dedicated deliver a high valued service package to our clients.

We have two main platforms in the proteomic analysis: label-free LC-MS based proteomics and SILIC LC-MS based proteomics. With our expertise in protein purification, protein immobilization protein chemistry and proteomic sample processing, we also provide add-on services to meet our clients’ various needs,  including sample isolation, protein purification, chemical labeling, immobilization on a solid phase,  pathway analysis, etc.  Our integrated services will help our clients in the study of phosphoproteomics. Chemoproteomics, organelle proteomics, signaling proteomics and other research areas.

5. Protein Mutation Analysis

(1)To find out the exact amino acid sequence of a commercially available protein product in which its amino acid sequence has been altered to give better or new properties; 

(2)Screening unwanted mutations at the protein level in clone selection process before the production of a protein therapeutics.

Many high commercial valued proteins, such as proteins used in industrial processes, contain amino acid sequences different from their native sequences, which give them superior properties than that of the native proteins. Since the exact amino acid sequence of such a modified protein is often non-disclosed, but the protein product is widely available, there is often a great interest in determining the exact amino acid sequences of those protein products. To meet the demand, we have developed analytic procedures and bioinformatics tools that can accurately and completely determine all mutations in protein products, even in the case that protein is heavily mutated throughout its entire sequence that gives it’s a new catalytic activity.

There are also needs to detect unwanted sequence changes in proteins. It becomes clear now that spontaneous mutations (also called sequence variant, SV) occur during cell line generation and storage.  A minor amount of SV in a production clone may lead to a high ratio of the final product. Since the sequence variants often have altered bioactivity and higher immunogenicity and are very difficult to remove, the presence of an even low level of a sequence variant in biomanufactory product may lead to a commercial disaster. Consequently, screening for unwanted mutations at protein level before large scale production is becoming a requirement although detecting SV is a difficult analytical task.  To help our clients meet this challenge, we have developed the that is capable of detecting SV as low as 0.01% and our screening cover the entire mAb/protein sequence, and we have carried out SV screening or several dozen therapeutic products for global pharmaceutical companies.

6. Antibody De Novo Sequencing

With as low as 100ug of a mAb protein, we can deliver a complete and accurate mAb protein sequences with distinguished leucine and isoleucine residues.  We guarantee a 100% accuracy of delivered mAb sequences. If the expressed mAb with our delivered sequences has lower activity than the original mAb in ELISA assay, we’ll continue our effect to identify possible sequence errors free of charge.

The development of bio-similar antibody for diagnostic or therapeutic use.

The development of antibody drugs based on commercially available antibody reagents. Some commercially available antibody reagents may have neutralizing activity toward a drug target. Direct sequencing such a reagent antibody may offer a good starting point for further development such as affinity maturation and humanization.

Resolving ambiguity from mAb gene sequencing. Due to the higher error rate in RT-PCR and technical difficulty in mAb gene sequencing itself, it is not rare that the result from mAb gene sequencing has ambiguity. The mAb protein sequencing is a faster and cost-saving way to resolve sequence conflict. 

7. Comparability Studies of Biologics

In the development of the biosimilar, it is impossible to produce a biologic drug that is identical to the innovator drug due to the complexity of biologics. Therefore, comparability studies which rely on analytical methods to compare the biosimilar to the innovator product are the requirement by various regulatory agencies in the drug development process. The structural and functional analyses are the key part of comparability study.

We has provided high-quality services to a large number of pharmaceutical and biotech companies in the Analytical Characterization of many Biosimilar products, including several some several biosimilar products have been approved in EU and US. Our biologic characterization service package includes Primary structure analysis (-N- and C-terminal sequence analysis, sequence variants analysis, peptide mapping); disulfide linkage analysis, isoelectric focusing, Glycan mapping, glycan structure determination by MS/MS fragmentation analysis, Glycan linkage analysis, Sialic acid analysis, Molecular weight distribution, etc.

8. Bio-Similar Development

We provide following service package to help our clients in the development of bio-similar antibodies. It contain following steps:

(1) Determining the exact sequences of a marketed antibody drug product .

(2)Developing CHO cell lines for antibody expression.

(3)Expression and purification of antibody in small amount.

(4)Conducting comparability study of expressed antibody with the marketed antibody drug as reference.

9. Antibody Fragments

We provide a service package making antibody fragments (Fab2 or Fab) from full-length monoclonal antibodies. Our technique platform allows > 90% conversion from full-length antibody to high purity antibody fragments. 

Application of antibody fragments

(1)As protein drugs

(2)As diagnostic and image agents

(3) As part of antibody-drug conjugates

10. Therapeutic Antibody Discovery

Our  therapeutic antibody discovery platform is based on our proprietary IDAS (Immunoglobulin Direct Affinity Selection) technology, in which high affinity antibodies are directly selected from animal serum based on antibody’s affinity towards immobilizes antigens. Combining with plasma cell sorting and antibody gene deep sequencing, our technology is capable of screening explore a large sequence space to discover the therapeutic antibodies with high affinity and in vivo optimized physicochemical properties.