How to Search NCBI Databases with Bio.Entrez.esearch() function?

Bio.Entrez.esearch() function allows you to search NCBI Databases with a given criteria. It uses the Entrez Web services provided by www.ncbi.nlm.nih.gov.

1. Search in PubMed for publications that include Biopython in their title. It returns 3 matches.

fyicenter$ python 
>>> from Bio import Entrez
>>> Entrez.email = "A.N.Other@example.com"

>>> handle = Entrez.esearch(db="pubmed", term="biopython[title]", retmax="40")
>>> record = Entrez.read(handle)

>>> record
{'Count': '3', 'RetMax': '3', 'RetStart': '0', 
 'IdList': ['34434786', '22909249', '19304878'], 
 'TranslationSet': [], 'QueryTranslation': '"biopython"[Title]'
}

2. Search for the matK gene in Cypripedioideae orchids in GenBank.

>>> handle = Entrez.esearch(
...   db="nucleotide", term="Cypripedioideae[Orgn] AND matK[Gene]", idtype="acc"
... )
>>> record = Entrez.read(handle)
>>> record["Count"]

>>> record["IdList"]
['NC_069974.1', 'NC_069973.1', 'NC_069972.1', 'NC_069971.1', 'NC_069970.1', ...]

⇒ Retrieve Record Summary with Bio.Entrez.esummary()

⇐ List NCBI Databases with Bio.Entrez.einfo()

⇑ Biopython - Tools for Biological Computation

⇑⇑ OBF (Open Bioinformatics Foundation) Tools