Nitrogen fixation by native Bradyrhizobia in symbiosis with Lupinus mariae-josephae requires a T3SS encoding a NopE-like effector


Autoria(s): Duran Wendt, David Ricardo; Pastor Martín, Victor; Zehner, Susanne; Göttfert, Michael; Imperial Ródenas, Juan; Ruiz Argüeso, Tomas-Andres; Rey Navarro, Luis
Data(s)

2013

Resumo

Several bradyrhizobial isolates from L. mariae-josephae root nodules [1] contain a type III secretion system (T3SS) within a cluster of about 30 genes. Among those genes, ttsI codes for the transcriptional activator of the system. Mutation of ttsI resulted in the formation of white, non-fixing nodules with the natural legume host, L. mariae-josephae. The T3SS cluster also contains a gene coding for a NopE-like protein. NopE proteins have been demonstrated to be effectors in the Bradyrhizobium-soybean symbiosis [2] and belong to a small group of poorly characterized proteins from plant-associated bacteria that contain one or two autocleavage motifs known as DUF1521 (Schirrmeister et al. 2011). The amino acid sequence of a NopE-like protein in the L. mariae-josephae strain LmjC contains just one autocatalytic motif. This is unlike NopE1 and NopE2 proteins secreted by the T3SS of B. japonicum, that contain two motifs [3]. The autocleavage of LmjC NopE protein was analyzed after expression in E. coli and purification. Two protein fragments of the predicted sizes appeared in the presence of Ca2+, Cu2+, Cd2+, Zn2+ and Mn2+ cations. In contrast, autocleavage did not take place in the presence of Ni2+, Co2+ or Mg2+. Site-directed mutagenesis of the DUF1521 motif in LmjC NopE abolished self-cleavage in vitro. Symbiotic competence of a NopE- mutant with the L. mariae-josephae host was not affected. Possible roles of NopE are discussed.

Formato

application/pdf

Identificador

http://oa.upm.es/29849/

Idioma(s)

eng

Relação

http://oa.upm.es/29849/1/INVE_MEM_2013_167599.pdf

info:eu-repo/semantics/altIdentifier/doi/null

Direitos

http://creativecommons.org/licenses/by-nc-nd/3.0/es/

info:eu-repo/semantics/openAccess

Fonte

Nitrogen fixation by native Bradyrhizobia in symbiosis with Lupinus mariae-josephae requires a T3SS encoding a NopE-like effector | XXXVI Congreso Sociedad Española de Bioquímica y Biología Molecular | 04/09/2013 - 06/09/2013 | Madrid, Spain

Palavras-Chave #Biología
Tipo

info:eu-repo/semantics/conferenceObject

Ponencia en Congreso o Jornada

PeerReviewed