Transglutaminase-mediated protein labelling: successes and challenges
Joelle
N.
Pelletier
Professor
of
Chemistry
Adjunct
Professor
of
Biochemistry
Université
de
Montréal
Wednesday,
September
4,
2019
9:00
a.m.
C2-361
(Reading
Room)
Abstract:
Engineering
enzyme-catalyzed
reactions
can
be
achieved
by
modifying
substrates
and
conditions
to
provide
routes
to
non-native
reactivity,
and
valuable
products.
The
microbial
transglutaminase
enzyme
(MTG)
has
been
heavily
used
in
the
food
industry
for
decades,
as
a
texturant.
MTG
efficiently
catalyzes
the
normally
costly
and
atom-expensive
formation
of
amide
bonds,
typically
between
proteins,
using
the
gamma-carboxamide
group
of
glutamine
and
the
ε-amino
group
of
lysine.
However,
it
can
be
diverted
to
include
synthetic
amine-bearing
substrates,
thus
expanding
the
amide-bond
forming
utility
of
MTG
in
protein
labelling.
We
demonstrate
that
various
non-native,
small-molecule
amines
react
efficiently
with
MTG.
We
will
present
the
MTG-catalyzed
formation
of
synthetically
attractive,
non-native
amides
such
as
proteins
modified
with
alkyne,
azide,
cyclooctene,
cyclooctyne
and
tetrazine-type
reagents.
Our
work
further
examines
the
scope
and
limitations
of
introducing
new
substrates
for
MTG-catalyzed
bioorthogonal
protein
labelling
reactions,
including
antibody
fragments.