Peptide Research Databases

This guide covers the major databases used in peptide research — what each one contains, how to search it, and when to use it.

Literature Databases

PubMed / MEDLINE

URL: https://pubmed.ncbi.nlm.nih.gov/

What it is: The primary database for biomedical literature. Maintained by the National Library of Medicine (NLM), it indexes over 36 million citations from ~5,200 journals.

What you'll find: Abstracts (and often full text) of peer-reviewed research papers, clinical trial reports, reviews, and meta-analyses.

How to search for peptides:

Tips:

• Use MeSH terms for precise subject searching
• Click "Cited by" on any paper to find newer research that references it
• Use the "Similar articles" feature to find related studies
• Save searches with email alerts for new publications

PubMed Central (PMC)

URL: https://www.ncbi.nlm.nih.gov/pmc/

What it is: The free full-text archive of biomedical and life sciences literature.

When to use it: When you need the complete paper, not just the abstract. PMC has over 8 million full-text articles.

Google Scholar

URL: https://scholar.google.com/

What it is: Google's academic search engine, covering journals, conference papers, theses, books, and preprints.

When to use it: For broader searches that include non-PubMed-indexed sources. Useful for finding citation counts and related work. Note: includes non-peer-reviewed content — always verify the source.

Clinical Trial Databases

ClinicalTrials.gov

URL: https://clinicaltrials.gov/

What it is: The U.S. National Library of Medicine's registry of clinical studies. Contains over 450,000 studies from 220+ countries.

What you'll find: Active, completed, and terminated human clinical trials, including study design, endpoints, enrollment status, and (sometimes) results.

How to search for peptides:

1. Enter the peptide name in the search bar
2. Filter by Status (Recruiting, Completed, Active)
3. Filter by Phase (Phase 1, 2, 3, 4)
4. Check the "Results" tab for completed studies

Key fields to check:

• NCT Number — unique trial identifier (e.g., NCT04235660)
• Phase — Phase 1 (safety), Phase 2 (efficacy), Phase 3 (large-scale), Phase 4 (post-market)
• Primary Outcome — what the study is actually measuring
• Sponsor — who is funding the trial

EU Clinical Trials Register

URL: https://www.clinicaltrialsregister.eu/

What it is: The European equivalent of ClinicalTrials.gov. Contains trials conducted in the EU and EEA.

WHO International Clinical Trials Registry Platform (ICTRP)

URL: https://trialsearch.who.int/

What it is: A meta-search across multiple national trial registries worldwide.

Chemical & Structural Databases

PubChem

URL: https://pubchem.ncbi.nlm.nih.gov/

What it is: The world's largest collection of freely accessible chemical information — over 115 million compounds.

What you'll find: Chemical structures, molecular formulas, molecular weights, physical properties, biological activities, safety data, and patent information for peptides and their components.

How to use for peptides:

1. Search by peptide name or CAS number
2. Check the "Biological Activities" section for bioassay data
3. Use the CID (Compound ID) for cross-referencing

ChEMBL

URL: https://www.ebi.ac.uk/chembl/

What it is: A curated database of bioactive molecules with drug-like properties. Maintained by the European Bioinformatics Institute (EBI).

What you'll find: Binding affinities, functional assays, ADMET (absorption, distribution, metabolism, excretion, toxicity) data, and target information for peptides.

When to use it: When you need pharmacological data — how strongly a peptide binds to its target, IC50/EC50 values, selectivity profiles.

Protein Data Bank (PDB)

URL: https://www.rcsb.org/

What it is: The global repository for 3D structural data of biological macromolecules.

What you'll find: Crystal structures, NMR structures, and cryo-EM structures of peptides and their receptor complexes.

When to use it: When you need to understand a peptide's 3D structure, how it binds to its receptor, or compare structural variants.

How to search:

1. Enter the peptide name or sequence
2. Filter by experimental method (X-ray, NMR, Cryo-EM)
3. Use the 3D viewer to visualize the structure

Protein & Sequence Databases

UniProt

URL: https://www.uniprot.org/

What it is: The most comprehensive protein sequence and functional annotation database.

What you'll find: Amino acid sequences, post-translational modifications, functional domains, tissue expression, subcellular localization, disease associations, and literature references.

When to use it: When you need the complete sequence of an endogenous peptide, its precursor protein, or its known functions and interactions.

How to search:

1. Search by peptide name, gene name, or accession number
2. Use the "Function" section for biological role
3. Check "Interaction" for known binding partners
4. Review "Expression" for tissue distribution

BLAST (Basic Local Alignment Search Tool)

URL: https://blast.ncbi.nlm.nih.gov/

What it is: A sequence similarity search tool.

When to use it: To find proteins or peptides with similar sequences, identify homologs across species, or check if a synthetic peptide matches any known natural sequence.

Specialized Peptide Databases

BIOPEP-UWM

URL: https://biochemia.uwm.edu.pl/biopep-uwm/

What it is: A database of biologically active peptide sequences, focused on food-derived and bioactive peptides.

SATPdb (Structure-Activity of Therapeutic Peptides Database)

URL: https://webs.iiitd.edu.in/raghava/satpdb/

What it is: A database of therapeutic peptides with structure-activity data.

APD3 (Antimicrobial Peptide Database)

URL: https://aps.unmc.edu/

What it is: A comprehensive database of antimicrobial peptides — relevant for peptides like LL-37 and other host defense peptides.

Regulatory Databases

FDA Drug Database

URL: https://www.accessdata.fda.gov/scripts/cder/daf/

What it is: Searchable database of FDA-approved drugs and biologics.

When to use it: To check if a peptide has FDA approval, review approved indications, read prescribing information, and check safety communications.

EMA (European Medicines Agency)

URL: https://www.ema.europa.eu/en/medicines

What it is: European regulatory database for approved and withdrawn medicines.

DrugBank

URL: https://go.drugbank.com/

What it is: A comprehensive database combining drug (including peptide) data with target, pathway, and interaction information.

How to Cross-Reference Databases

For thorough peptide research, use multiple databases together:

Tips for Effective Database Searching

1. Use multiple synonyms. Peptides often have several names — search all of them.
2. Check CAS numbers. CAS numbers are unique identifiers that work across all chemistry databases.
3. Use Boolean operators. AND narrows results; OR broadens them; NOT excludes terms.
4. Set date filters. Peptide research moves fast — filter for recent publications.
5. Follow citation chains. Use "Cited by" in PubMed and Google Scholar to find newer related work.
6. Save searches. Most databases let you save searches and set up email alerts.
7. Cross-validate. Never rely on a single database — cross-reference across sources.