With no explanation, label each line with "O", "other-chemicalthing", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
This
enzyme
participates
in
glycine
,
serine
and
threonine
metabolism
and
vitamin
B6
metabolism
.
This:O
enzyme:O
participates:O
in:O
glycine:other-chemicalthing
,:O
serine:other-chemicalthing
and:O
threonine:other-chemicalthing
metabolism:O
and:O
vitamin:other-chemicalthing
B6:other-chemicalthing
metabolism:O
.:O