Construction of EGFP-Labeling System for Visualizing the Infection Process of Xanthomonas axonopodis pv. citri in planta

Abstract

Xanthomonas axonopodis pv. citri (Xac) is the causal agent of citrus bacterial canker, an economically important disease to world citrus industry. To monitor the infection process of Xac in different citrus plants, the enhanced green florescent protein (EGFP) visualizing system was constructed to visualize the propagation and localization in planta. First, the wild-type Xac was isolated from the diseased leaves of susceptible 'Bingtang' sweet orange, and then the isolated Xac was labeled with EGFP by triparental mating. After PCR identification, the growth kinetics and pathogenicity of the transformants were analyzed in comparison with the wild-type Xac. The EGFP-labeled bacteria were inoculated by spraying on the surface and infiltration in the mesophyll of 'Bingtang' sweet orange leaves. The bacterial cell multiplication and diffusion processes were observed directly under confocal laser scanning microscope at different intervals after inoculation. The results indicated that the EGFP-labeled Xac releasing clear green fluorescence light under fluorescent microscope showed the infection process and had the same pathogenicity as the wild type to citrus. Consequently, the labeled Xac demonstrated the ability as an efficient tool to monitor the pathogen infection.

Isolation and Characterization of a Phosphorus-Solubilizing Bacterium from Rhizosphere Soils and Its Colonization of Chinese Cabbage (Brassica campestris ssp. chinensis)

“…To obtain a stable genetic transformation, the target gene was introduced into YL6 by a triparental mating (Liu et al, 2012). The GFP-expressing YL6 strain (YL6-GFP) was similar to the original strain (YL6), both in its growth and ability to dissolve P. The ability of PSB survival in the soil is the key to determining its role in the natural environment and is an important basis on which to evaluate PSB colonization ability in the rhizosphere (Shen et al, 2013; Hanif et al, 2015).…”

Efficient Delivery of dsRNA and DNA in Cultured Silkworm Cells for Gene Function Analysis Using PAMAM Dendrimers System

“…Enhanced green fluorescent protein (EGFP) and red fluorescent protein (Red) expressed in prokaryotic and eukaryotic cells are capable of producing strong green and red fluorescence when excited by illumination with ultraviolet, respectively, which makes them excellent reporters for in vivo observation [33,34]. Fusion expression of fluorescent protein for a target protein has been extensively used for direct visualization of a target protein in various cells and organs using confocal microscopy.…”

Infection Process of Burkholderia glumae in Rice Spikelets

“…; Liu et al. ). Both metabolically active and starving bacterial cells can be detected by the expression of the GFP marker (Unge and Jansson ; Campos‐Soriano and Segundo ).…”

“…citri, Herbcrspirillztm sp. and Klebsiella oxytoca Zakria et al 2007;Liu et al 2012). Both metabolically active and starving bacterial cells can be detected by the expression of the GFP marker (Unge and Jansson 2001;Campos-Soriano and Segundo 2009).…”