Bacterial pleckstrin homology domains: a prokaryotic origin for the PH domain.
Pleckstrin homology (PH) domains have been identified only in eukaryotic proteins to date. We have determined crystal structures for three members of an uncharacterized protein family (Pfam PF08000), which provide compelling evidence for the existence of PH-like domains in bacteria (PHb). The first two structures contain a single PHb domain that forms a dome-shaped, oligomeric ring with C(5) symmetry. The third structure has an additional helical hairpin attached at the C-terminus and forms a similar but much larger ring with C(12) symmetry. Thus, both molecular assemblies exhibit rare, higher-order, cyclic symmetry but preserve a similar arrangement of their PHb domains, which gives rise to a conserved hydrophilic surface at the intersection of the beta-strands of adjacent protomers that likely mediates protein-protein interactions. As a result of these structures, additional families of PHb domains were identified, suggesting that PH domains are much more widespread than originally anticipated. Thus, rather than being a eukaryotic innovation, the PH domain superfamily appears to have existed before prokaryotes and eukaryotes diverged.
Xu
Qingping
Q
Joint Center for Structural Genomics, Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA.
Bateman
Alex
A
Finn
Robert D
RD
Abdubek
Polat
P
Astakhova
Tamara
T
Axelrod
Herbert L
HL
Bakolitsa
Constantina
C
Carlton
Dennis
D
Chen
Connie
C
Chiu
Hsiu-Ju
HJ
Chiu
Michelle
M
Clayton
Thomas
T
Das
Debanu
D
Deller
Marc C
MC
Duan
Lian
L
Ellrott
Kyle
K
Ernst
Dustin
D
Farr
Carol L
CL
Feuerhelm
Julie
J
Grant
Joanna C
JC
Grzechnik
Anna
A
Han
Gye Won
GW
Jaroszewski
Lukasz
L
Jin
Kevin K
KK
Klock
Heath E
HE
Knuth
Mark W
MW
Kozbial
Piotr
P
Krishna
S Sri
SS
Kumar
Abhinav
A
Marciano
David
D
McMullan
Daniel
D
Miller
Mitchell D
MD
Morse
Andrew T
AT
Nigoghossian
Edward
E
Nopakun
Amanda
A
Okach
Linda
L
Puckett
Christina
C
Reyes
Ron
R
Rife
Christopher L
CL
Sefcovic
Natasha
N
Tien
Henry J
HJ
Trame
Christine B
CB
van den Bedem
Henry
H
Weekes
Dana
D
Wooten
Tiffany
T
Hodgson
Keith O
KO
Wooley
John
J
Elsliger
Marc-André
MA
Deacon
Ashley M
AM
Godzik
Adam
A
Lesley
Scott A
SA
Wilson
Ian A
IA
D000595:Amino Acid Sequence; D001419:Bacteria / Q000378:metabolism*; D001426:Bacterial Proteins / Q000737:chemistry*; D001665:Binding Sites; D017124:Conserved Sequence; D018360:Crystallography, X-Ray; D005057:Eukaryotic Cells; D019143:Evolution, Molecular; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011387:Prokaryotic Cells / Q000378:metabolism*; D011485:Protein Binding; D020836:Protein Structure, Quaternary; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013499:Surface Properties
D001426:Bacterial Proteins