Resources

Proteomics Databases



Metabolomics Databases

• • Mass Spectrometry-Based Host Cell Protein Analysis: Principles, Workflow, and Benefits

  In the biopharmaceutical field, recombinant protein therapeutics, such as monoclonal antibodies and fusion proteins, expressed and purified in mammalian cells, for example CHO cells, often contain a significant impurity: host cell proteins (HCPs). If HCPs are not thoroughly removed during downstream purification, they can induce immunogenic responses, compromise drug stability, and even pose safety risks to patients. Consequently, accurate identification and quantification of HCPs is a critical step i......

• • LC-MS/MS Workflow for Disulfide Bond Mapping Analysis

  Disulfide bonds are critical covalent linkages that maintain the stability of protein tertiary and quaternary structures, playing essential roles in protein structural characterization and biopharmaceutical development. In particular, in antibody therapeutics, recombinant proteins, and complex biopharmaceutical formulations, correct disulfide bond pairing directly influences protein folding conformation, biological activity, and safety. Consequently, LC-MS/MS-based disulfide bond mapping has emerged a......

• • Antibody Protein Sequencing: How Mass Spectrometry Reconstructs Antibody Variable-Region Sequences

  Antibody variable-region sequences define antigen recognition, yet many projects still lack a reliable genetic record for the antibody in hand. Hybridoma cells may be lost, expression plasmids may be incomplete, and legacy purified IgG may remain the only usable material. In these cases, researchers need primary structure evidence derived directly from the antibody protein rather than from amplifiable nucleic acids.

• • Planning an Antibody Protein Sequencing Project: Budget, Scope, and Vendor Deliverables

  Once a team decides to recover VH and VL sequence from purified IgG, the next questions are often practical rather than scientific. How much budget is realistic? What scope is required for recombinant handoff, publication, or QC documentation? Which deliverables separate a usable report from a partial sequence summary that cannot support the next decision?

• • Purified IgG or Hybridoma Cells? Selecting the Antibody Sequence Recovery Route for Your Project

  Antibody sequence recovery projects rarely fail because the binder is unknown. They fail because the team starts with the wrong material assumption. One project may have only an old IgG aliquot in the freezer. Another may still maintain a low-passage hybridoma culture with no sequence file. A third may hold a recombinant lot that must be verified before tech transfer. Each starting point supports a different recovery route.

• • Sparse VH/VL Coverage in Antibody Protein Sequencing: Digest, Purity, and LC-MS/MS Recovery Fixes

  A purified IgG sample can look acceptable on a Coomassie gel and still produce disappointing sequencing results. LC-MS/MS may run cleanly, yet variable-region coverage remains thin, CDR3 evidence is weak, or heavy-chain and light-chain assembly stops short of a usable VH/VL pair. For teams preparing recombinant expression, legacy clone rescue, or documentation submissions, sparse coverage creates immediate schedule risk.

• • From Purified IgG to VH/VL Sequence: Antibody Protein Sequencing for Legacy and Recombinant Antibodies

  Many antibody projects stall not because the binder fails functionally, but because the sequence record is incomplete. A legacy hybridoma may still produce IgG in supernatant, yet lab notebooks contain no VH or VL files. A recombinant lot may pass binding QC while the team still needs primary structure evidence for tech transfer. A comparator antibody may require documented sequence support before analytical similarity work can proceed.

• • Edman Sequencing or LC-MS/MS for N-Terminal Analysis? Matching the Method to Your Sample and QC Goal

  Introduction N-terminal analysis projects rarely fail because teams lack analytical capability. They fail because the selected method does not match the sample chemistry or the evidence standard required for the next decision. One team may need a direct ten-residue N-terminal read for lot release.

• • Scoping an Edman Sequencing Project: Sample Requirements, Cycle Count, and Report Deliverables

  Introduction Edman sequencing projects move faster when scope is defined before samples ship. Teams often request a fixed number of cycles without confirming whether the material supports that read length, whether the N-terminus is accessible, or whether the final report must satisfy internal QC, regulatory documentation, or publication standards.

• • Hybridoma Sequencing When Recovery Fails: A Practical Troubleshooting Guide

  When hybridoma recovery stalls, the priority is to determine whether the problem lies in the cells, the nucleic acid material, the amplification design, or the original project assumptions. If your team is troubleshooting a failed recovery attempt or preparing a low-passage culture for the first time, MtoZ Biolabs can Assess hybridoma readiness and recommend next steps before material is resubmitted.