Unusual α-Carbon Hydroxylation of Proline Promotes Active-Site Maturation.
The full extent of proline (Pro) hydroxylation has yet to be established, as it is largely unexplored in bacteria. We describe here a so far unknown Pro hydroxylation activity which occurs in active sites of polysaccharide deacetylases (PDAs) from bacterial pathogens, modifying the protein backbone at the Cαatom of a Pro residue to produce 2-hydroxyproline (2-Hyp). This process modifies with high specificity a conserved Pro, shares with the deacetylation reaction the same active site and one catalytic residue, and utilizes molecular oxygen as source for the hydroxyl group oxygen of 2-Hyp. By providing additional hydrogen-bonding capacity, the Pro→2-Hyp conversion alters the active site and enhances significantly deacetylase activity, probably by creating a more favorable environment for transition-state stabilization. Our results classify this process as an active-site "maturation", which is highly atypical in being a protein backbone-modifying activity, rather than a side-chain-modifying one.
Institute of Molecular Biology and Biotechnology , 70013 Heraklion, Crete, Greece.
Vasiliki E
VE
Fadouloglou
Institute of Molecular Biology and Biotechnology , 70013 Heraklion, Crete, Greece.|Department of Biology, University of Crete , Voutes University Campus, 70013 Heraklion, Crete, Greece.
Stavroula
S
Balomenou
Institute of Molecular Biology and Biotechnology , 70013 Heraklion, Crete, Greece.
Michalis
M
Aivaliotis
Institute of Molecular Biology and Biotechnology , 70013 Heraklion, Crete, Greece.
Dina
D
Kotsifaki
Department of Biology, University of Crete , Voutes University Campus, 70013 Heraklion, Crete, Greece.
Sofia
S
Arnaouteli
Department of Biology, University of Crete , Voutes University Campus, 70013 Heraklion, Crete, Greece.
Anastasia
A
Tomatsidou
Institute of Molecular Biology and Biotechnology , 70013 Heraklion, Crete, Greece.
Giorgos
G
Efstathiou
Institute of Molecular Biology and Biotechnology , 70013 Heraklion, Crete, Greece.
Nikos
N
Kountourakis
Institute of Molecular Biology and Biotechnology , 70013 Heraklion, Crete, Greece.
Sofia
S
Miliara
Department of Biology, University of Crete , Voutes University Campus, 70013 Heraklion, Crete, Greece.
Marianna
M
Griniezaki
Department of Biology, University of Crete , Voutes University Campus, 70013 Heraklion, Crete, Greece.
Aleka
A
Tsalafouta
Department of Chemistry, University of Crete , Voutes University Campus, 70013 Heraklion, Crete, Greece.
Spiros A
SA
Pergantis
Biology and Genetics of the Bacterial Cell Wall Unit, Institut Pasteur , 75015 Paris, France.|INSERM , Equipe Avenir, Paris, France.
Ivo G
IG
Boneca
Department of Molecular Biology and Genetics, Democritus University of Thrace , University Campus, 68100 Alexandroupolis, Greece.
Nicholas M
0000-0003-3782-206X
NM
Glykos
Institute of Molecular Biology and Biotechnology , 70013 Heraklion, Crete, Greece.|Department of Biology, University of Crete , Voutes University Campus, 70013 Heraklion, Crete, Greece.
Vassilis
V
Bouriotis
Institute of Molecular Biology and Biotechnology , 70013 Heraklion, Crete, Greece.|Department of Biology, University of Crete , Voutes University Campus, 70013 Heraklion, Crete, Greece.
Michael
0000-0002-3112-6904
M
Kokkinidis
D000581:Amidohydrolases / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D001408:Bacillus anthracis / Q000201:enzymology*; D001409:Bacillus cereus / Q000201:enzymology*; D001665:Binding Sites; D002244:Carbon / Q000737:chemistry / Q000378:metabolism*; D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D006900:Hydroxylation; D008958:Models, Molecular; D011392:Proline / Q000737:chemistry / Q000378:metabolism*
D002244:Carbon; D011392:Proline; D000581:Amidohydrolases; C022427:polysaccharide deacetylase