Assertion: peptide's acid | /r/AtLocation | bacterial envelopes
Facets:
value: as a neuromodulator
type: PURPOSE
value: in some antibiotics
type: LOCATION
Source sentences:
text: These are all L -stereoisomers ("left-handed" isomers), although a few D -amino acids ("right-handed") occur in bacterial envelopes, as a neuromodulator ( D -serine), and in some antibiotics.