Research
Pilus biogenesis
Bacterial pili are hair-like surface-exposed organelles. They
are responsible for recognition of and attachment to the host
and thus, are also crucial virulence factors. Pili are polymer of
protein subunits, the assembly of which require accessory
proteins. There are two biogenesis pathways for the
production of pili in Gram-negative bacteria: the chaperone-
usher pathway and the type IV pilus biogenesis pathway - not
to be confused with T4S systems! We are engaged in research
on both, but have made most progress on the former.
Chaperone-usher (CU) pili have clear relevance in the
pathogenicity of uropathogenic Escherichia coli, where CU pili
mediate bacterial tropism to the bladder to cause cystitis or
to the kidney to cause pyolenephritis. CU pili require two
accessory proteins for biogenesis: a chaperone that stabilises
pilus subunits and ferries them to an assembly platform, the
usher, the second accessory protein required in this system.
The usher is an extraordinary molecular nanomachine
embedded in the outer membrane. It drives subunit
recruitment, polymerisation and secretion. All in one protein!
References
Please click on the links below to download recent reviews and also our landmark papers in Nature, Science, and Cell.
Hospenthal
MK,
Redzej
A,
Dodson
K,
Ukleja
M,
Frenz
B,
Rodrigues
C,
Hultgren
SJ,
DiMaio
F,
Egelman
EH,
Waksman
G
(2016)
Structure
of
a
Chaperone-Usher Pilus Reveals the Molecular Basis of Rod Uncoiling
.
Cell
164, 269–278
Geibel
S,
Procko
E,
Hultgren
SJ,
Baker
D,
Waksman
G
(2013)
Structural
and
energetic
basis
of
folded-protein
transport
by
the
FimD
usher
.
Nature
. Apr 11;496(7444):243-6. doi: 10.1038/nature12007.
G.
Phan,
H.
Remaut,
T.Wang,
W.
Allen,
K.
Pirker,
A.
Lebedev,
N.
Henderson,
S.
Geibel,
E.
Volkan,
J.
Yan,
M.
Kunze,
J.
Pinkner,
B.
Ford,
C.
Kay,
H.
Li,
S.
Hultgren,
D.
Thanassi,
and
Waksman
G
(2011).
Crystal
structure
of
the
FimD
usher
bound
to
its
cognate
FimC:FimH
substrate
.
Nature
. 474:49-53.
F.
G.
Sauer,
J.
Pinkner,
G.
Waksman
,
and
S.J.Hultgren
(2002)
Chaperone
Priming
of
Pilus
Subunit
Facilitates
a
Topological
Transition
that
Drives Fiber Formation
.
Cell
. 111:543-51.
Waksman sole corresponding author
K.W.
Dodson,
J.S.
Pinkner,
T.
Rose,
G.
Magnusson,
S.J.
Hultgren,
and
Waksman
G
(2001).
Structural
Basis
of
Tropism
of
Pyelonephritic
/E.
coli/ for the Human Kidney
.
Cell.
105:733–743.
F.G.
Sauer,
K.
Fütterer,
J.S.
Pinkner,
K.W.
Dodson,
S.J.
Hultgren,
and
Waksman
G
(1999).
Structural
basis
of
chaperone
function
and
pilus
biogenesis
.
Science
. 285:1058-1061.
Pui