Antifungal and Root Surface Colonization Properties of GFP-Tagged Paenibacillus brasilensis PB177

Abstract

This study evaluates the potential of Paenibacillus brasilensis strain PB177 to inhibit phytopathogenic fungi commonly causing maize diseases and to colonize maize plants. In vitro assays demonstrated antagonistic activity against the fungal pathogens, Fusarium moniliforme and Diplodia macrospora. The PB177 strain was tagged with the gfp gene, encoding the green fluorescent protein (GFP) and GFP-tagged bacteria were detected attached to maize roots by stereo-and confocal microscopy. The GFP-tagged bacteria were also used to treat maize seeds before challenging the seeds with two phytopathogenic fungi. The results demonstrated that the bacterial cells are mobilized to the maize roots in the presence of the fungal pathogens. The ability of P. brasilensis PB177 to inhibit fungal growth in vitro and its capability of colonization of maize roots in vivo suggest a potential application of this strain as a biological control agent. This is the first report on the successful introduction of the GFP marker gene into a P. brasilensis strain, enabling the direct observation of these promising plant growth promoting bacteria on maize roots in situ.

A new bioorganic fertilizer can effectively control banana wilt by strong colonization with Bacillus subtilis N11

“…However, the instability of plasmid pHAPII in the transformant limited its usefulness in long-term experiments. Some researchers have reported that the plasmid was stably maintained for several months in the transformants without selection (Njoloma et al 2006;Timmusk et al 2005), while others demonstrated that the plasmid was lost even within several days without antibiotic selection (von der Weid et al 2005). Thus, different strains and plasmids may show different plasmid maintenance.…”

“…It has previously been shown that bacteria could colonize plant surfaces, such as roots and leaves, often by forming aggregates or microcolonies (Assmus et al 1995;Dandurand et al 1997;von der Weid et al 2005). Different biocontrol strains are known to colonize different regions of plants (Tombolini et al 1999;Ramos et al 2000;Walker et al 2002).…”

“…Therefore, GFP is widely used to identify and quantify specific microbes or activities in a complicated environmental sample such as soil and plant tissues (Chelius and Triplett 2000). The potential for in situ monitoring of GFPtagged bacteria on plant roots has previously been demonstrated (Timmusk et al 2005;von der Weid et al 2005;Liu et al 2006;Njoloma et al 2006). However, to our knowledge, the colonization of B. subtilis on banana roots has not been reported.…”

Molecular tools in rhizosphere microbiology—from single-cell to whole-community analysis

“…In addition, visualization methods, such as dual-channel imaging (Bernhardt et al 1999), allow the rapid detection of regulatory networks which are induced by environmental changes, by combining autoradiography and a silver-stained electropherogram (see below). Because of the above, two-dimensional gel electrophoresis has become a very powerful tool to resolve proteins, which are the final stage of gene expression (Volker and Hecker 2005). However, this method is incomplete because the routine analysis does not enable the analysis of several groups of proteins: membrane proteins, highly alkaline proteins, and rare proteins.…”

Effect of endophytic Bacillus sp. from selected medicinal plants on growth promotion and diosgenin production in Trigonella foenum-graecum

“…They have been reported to be well equipped with Plant Growth promoting (PGP) properties like fixation of nitrogen (Von Der Weid et al 2002), and production of auxins (Lebuhn et al 1997;Bent et al 2001;Da Mota et al 2008) and cytokinin . Bacillus strains have also been reported widely for their ability to suppress pathogens (Von Der Weid et al 2005) and increase the resistance of the plant against diseases (Timmusk and Wagner 1999). Bacillus species with endophytic origin can thus offer highly promising agronomical application as plant probiotics and their long term survival in the host is of great significance to be exploited.…”