Two serine residues in Pseudomonas syringae effector HopZ1a are required for acetyltransferase activity and association with the host co-factor.
New Phytol
; 208(4): 1157-68, 2015 Dec.
Article
en En
| MEDLINE
| ID: mdl-26103463
ABSTRACT
Gram-negative bacteria inject type III secreted effectors (T3SEs) into host cells to manipulate the immune response. The YopJ family effector HopZ1a produced by the plant pathogen Pseudomonas syringae possesses acetyltransferase activity and acetylates plant proteins to facilitate infection. Using mass spectrometry, we identified a threonine residue, T346, as the main autoacetylation site of HopZ1a. Two neighboring serine residues, S349 and S351, are required for the acetyltransferase activity of HopZ1a in vitro and are indispensable for the virulence function of HopZ1a in Arabidopsis thaliana. Using proton nuclear magnetic resonance (NMR), we observed a conformational change of HopZ1a in the presence of inositol hexakisphosphate (IP6), which acts as a eukaryotic co-factor and significantly enhances the acetyltransferase activity of several YopJ family effectors. S349 and S351 are required for IP6-binding-mediated conformational change of HopZ1a. S349 and S351 are located in a conserved region in the C-terminal domain of YopJ family effectors. Mutations of the corresponding serine(s) in two other effectors, HopZ3 of P. syringae and PopP2 of Ralstonia solanacerum, also abolished their acetyltransferase activity. These results suggest that, in addition to the highly conserved catalytic residues, YopJ family effectors also require conserved serine(s) in the C-terminal domain for their enzymatic activity.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Enfermedades de las Plantas
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Serina
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Acetiltransferasas
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Arabidopsis
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Proteínas de Arabidopsis
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Factores de Virulencia
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Pseudomonas syringae
Tipo de estudio:
Prognostic_studies
/
Risk_factors_studies
Idioma:
En
Revista:
New Phytol
Asunto de la revista:
BOTANICA
Año:
2015
Tipo del documento:
Article
País de afiliación:
Estados Unidos