Identifier types that can be used for a physical entity search:

3dmet
amaze
aracyc
arrayexpress
beilstein
bigg
bind
bindingdb
biocarta
biogrid
cas
cazy
ccsd
chebi
chembl
chembl compound
chemspider
corum
cosmic
dip
disprot
dpd
drugbank
ec
ecocyc
efo
ehmn
embl
emdb
ensembl
entrez
entrez-gene
entrez-gi
genatlas
genbank
genbank_nucl_gi
genbank_protein_gi
genecards
glycomedb
go
het
hgnc-id
hgnc-symbol
hmdb
hmdb_metabolite
hprd
huge
humancyc
ier_0000001
ier_0000002
ier_0000006
ier_0000008
imex
innatedb
inoh
intact
interpro
ipi
ipr
jcggdb
kegg
kegg glycan
kegg-glycan
knapsack
ligandbox
lipid_maps
lipidbank
lipidmaps
locuslink
matrixdb
mdl
merck index
mesh
metabolights
mgd
mim
mint
mips
mirbase
mmdb
moped
mpidb
ncbi nucleotide
ncbi-proteinid
nci
ndcd
netpath
nikkaji
omim
panther
pdb
pdb-ccd
pdbe
pdbsum
pfam
pharmgkb
phosphosite
phosphositeplus
phylomedb
pid
pid-gene
pig
pin
pride
prints
prosite
proteinmodelportal
proteomexchange
psi-mi
pubchem
pubchem-compound
pubchem-substance
pubmed
rcsb pdb
reactome
refseq
rnacentral
smart
smpdb
smr
so
spike
string
superdrug
tair
ttd
ucsc
um-bbd-cpd
unigene
uniparc
uniprot
uniprot knowledge base
uniprotkb
vega
wikipathways
wikipedia
wwpdb
zinc