Premium
Purification and phosphorylation of the effector protein NopL from Rhizobium sp. NGR234
Author(s) -
Bartsev Alexander V.,
Boukli Nawal M.,
Deakin William J.,
Staehelin Christian,
Broughton William J.
Publication year - 2003
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/s0014-5793(03)01145-1
Subject(s) - effector , biology , protein kinase a , kinase , type three secretion system , phosphorylation , biochemistry , microbiology and biotechnology , signal transduction , secretion , virulence , gene
Bacterial pathogens use type III secretion systems (TTSSs) to deliver virulence factors into eukaryotic cells. These effectors perturb host‐defence responses, especially signal transduction pathways. A functional TTSS was identified in the symbiotic, nitrogen‐fixing bacterium Rhizobium sp. NGR234. NopL (formerly y4xL) of NGR234 is a putative symbiotic effector that modulates nodulation in legumes. To test whether NopL could interact with plant proteins, in vitro phosphorylation experiments were performed using recombinant nopL protein purified from Escherichia coli as well as protein extracts from Lotus japonicus and tobacco plants. NopL serves as a substrate for plant protein kinases as well as purified protein kinase A. Phosphorylation of NopL was inhibited by the Ser/Thr kinase inhibitor K252a as well as by PD98059, a mitogen‐activated protein (MAP) kinase kinase inhibitor. It thus seems likely that, after delivery into the plant cell, NopL modulates MAP kinase pathways.