RT Journal Article
T1 Genes ptz and idi, Coding for Cytokinin Biosynthesis Enzymes, Are Essential for Tumorigenesis and In Planta Growth by P. syringae pv. savastanoi NCPPB 3335
A1 Añorga, Maite
A1 Pintado Calvillo, Adrián
A1 Ramos-Rodríguez, Cayo Juan
A1 De Diego, Nuria
A1 Ugena, Lydia
A1 Novak, Ondrej
A1 Murillo, Jesús
K1 Hormonas vegetales
K1 Bacterias fitopatógenas
K1 Carcinogénesis
AB The phytopathogenic bacterium Pseudomonas syringae pv. savastanoi elicits aerial tumors on olive plants and is also able to synthesize large amounts of auxins and cytokinins. The auxin indoleacetic acid was shown to be required for tumorigenesis, but there is only correlational evidence suggesting a role for cytokinins. The model strain NCPPB 3335 contains two plasmid-borne genes coding for cytokinin biosynthesis enzymes: ptz, for an isopentenyl transferase and idi, for an isopentenyl-diphosphate delta-isomerase. Phylogenetic analyses showed that carriage of ptz and idi is not strictly associated with tumorigenic bacteria, that both genes were linked when first acquired by P. syringae, and that a different allele of ptz has been independently acquired by P. syringae pv. savastanoi and closely related bacteria. We generated mutant derivatives of NCPPB 3335 cured of virulence plasmids or with site-specific deletions of genes ptz and/or idi and evaluated their virulence in lignified and micropropagated olive plants. Strains lacking ptz, idi, or both produced tumors with average volumes up to 29 times smaller and reached populations up to two orders of magnitude lower than those induced by strain NCPPB 3335; these phenotypes reverted by complementation with the cloned genes. Trans-zeatin was the most abundant cytokinin in culture filtrates of NCPPB 3335. Deletion of gene ptz abolished biosynthesis of trans-zeatin and dihydrozeatin, whereas a reduced but significant amount of isopentenyladenine was still detected in the medium, suggesting the existence of other genes contributing to cytokinin biosynthesis in P. syringae.
PB Frontiers Media
YR 2020
FD 2020-08-21
LK https://hdl.handle.net/10630/39014
UL https://hdl.handle.net/10630/39014
LA eng
NO Front. Plant. Sci. 11:1294.
NO AP, CR, and JM were supported by grants FPU14/05551, AGL2017-82492-C2-1-R and AGL2017-82492-C2-2-R, respectively, from Ministerio de Ciencia, Innovación y Universidades (Spain), cofinanced by the Fondo Europeo de Desarrollo Regional (FEDER). ND, LU, and ON were supported by grant CZ.02.1.01/0.0/0.0/16_019/0000827, within the program Research, Development and Education (OP RDE).
DS RIUMA. Repositorio Institucional de la Universidad de Málaga
RD 28 feb 2026