Recombinant Human Carboxypeptidase D (CPD) is produced using a baculovirus expression system and spans the amino acid region 383-461. The protein includes an N-terminal 10xHis-tag and a C-terminal Myc-tag, which help with purification and detection. This recombinant protein shows a purity of over 85% as determined by SDS-PAGE, suggesting reliable performance in experimental applications.
Carboxypeptidase D is a metallocarboxypeptidase involved in protein processing and peptide hormone maturation. It appears to play a role in removing C-terminal arginine or lysine residues from peptides, which is crucial in various biological pathways. Understanding CPD's function and regulation may be essential for research in cellular processes and enzymatic activity.
Potential Applications
Note: The applications listed below are based on what we know about this protein's biological functions, published research, and experience from experts in the field. However, we haven't fully tested all of these applications ourselves yet. We'd recommend running some preliminary tests first to make sure they work for your specific research goals.
The recombinant human carboxypeptidase D (CPD) fragment (383–461aa) expressed via the baculovirus system is a partial fragment representing only a small portion of the full-length enzyme (which is ~1380 amino acids). CPD is a membrane-associated zinc-dependent metallocarboxypeptidase containing multiple functional domains and requires correct tertiary organization for enzymatic activity. Because this fragment (383–461aa) is outside the catalytic core and represents only a short region of the middle domain, it is not expected to possess enzymatic activity. However, the baculovirus (insect) expression system provides eukaryotic folding machinery and potential post-translational modifications, increasing the likelihood that the fragment adopts a locally native secondary structure relevant to its region in the full protein. Thus, the protein is likely to be correctly folded at the local level but biologically inactive as an enzyme. It remains suitable for antibody production, structural characterization, and interaction mapping if those interactions involve this specific region of CPD.
1. Protein-Protein Interaction Studies
This dual-tagged CPD fragment (383–461aa) may be useful for identifying potential binding partners that interact with this portion of the C-terminal region. If the recombinant fragment retains partial folding (as likely in the baculovirus system), it can be employed in pull-down or affinity-based assays to map localized protein-binding sites. If misfolding occurs, the fragment may still serve as a screening reagent for linear motif-dependent interactions but would not reflect native conformational binding. Hence, it should be used primarily for mapping or preliminary screening rather than for confirming physiological protein interactions involving full-length CPD.
2. Antibody Development and Validation
This recombinant fragment is well-suited for generating and validating region-specific antibodies targeting the 383–461aa domain of human CPD. If folded correctly, antibodies generated may recognize conformational epitopes within this domain. If partially unfolded, antibodies will primarily target linear epitopes, suitable for Western blotting or ELISA but not necessarily for recognizing native CPD in cells. The dual-tag configuration (His at N-terminus and Myc at C-terminus) facilitates purification and assay-based validation of antibody specificity.
3. Structural and Biochemical Characterization
This fragment may be used for biophysical and structural characterization, including CD spectroscopy, DLS, or limited proteolysis assays to assess folding and stability. If properly folded (likely given baculovirus expression), it can provide local structural insight into the conformation of this CPD region. However, as it lacks the catalytic residues and overall domain architecture, it cannot represent the enzyme’s biochemical activity or full structural behavior. Thus, this application should be limited to domain-level folding and stability analysis, not enzymatic function.
4. Tag-Based Detection and Quantification Assays
The dual-tagged construct can be reliably used as a control protein or detection reagent in ELISA or Western blot systems utilizing anti-His or anti-Myc antibodies. If properly folded, it may serve as a model fragment for studying CPD expression or trafficking. If partially misfolded, it remains suitable as a quantitative standard or assay calibration protein for tag-based systems, since tag exposure is not folding-dependent. Thus, this fragment is well-suited for tag-based detection and quality control assays.
