Expression of a Synthesized Gene Encoding Cationic Peptide Cecropin B in Transgenic Tomato Plants Protects against Bacterial Diseases

Abstract

The cationic lytic peptide cecropin B (CB), isolated from the giant silk moth (Hyalophora cecropia), has been shown to effectively eliminate Gram-negative and some Gram-positive bacteria. In this study, the effects of chemically synthesized CB on plant pathogens were investigated. The S 50 s (the peptide concentrations causing 50% survival of a pathogenic bacterium) of CB against two major pathogens of the tomato, Ralstonia solanacearum and Xanthomonas campestris pv. vesicatoria, were 529.6 g/ml and 0.29 g/ml, respectively. The CB gene was then fused to the secretory signal peptide (sp) sequence from the barley ␣-amylase gene, and the new construct, pBI121-spCB, was used for the transformation of tomato plants. Integration of the CB gene into the tomato genome was confirmed by PCR, and its expression was confirmed by Western blot analyses. In vivo studies of the transgenic tomato plant demonstrated significant resistance to bacterial wilt and bacterial spot. The levels of CB expressed in transgenic tomato plants (ϳ0.05 g in 50 mg of leaves) were far lower than the S 50 determined in vitro. CB transgenic tomatoes could therefore be a new mode of bioprotection against these two plant diseases with significant agricultural applications.

Transgenic tobacco plants expressing antimicrobial peptide bovine lactoferricin show enhanced resistance to phytopathogens

“…In the present study, transgenic tobacco plants expressing the Lfc gene were developed to enhance resistance against a broad spectrum of plant pathogens. As a result, Lfc exhibited bactericidal activity as high as bactericidal peptides, such as sarcotoxin IA derived from fresh y Sarcophaga peregrina (Ohshima et al 1999) and cecropin derived from giant silk moth Hylophora cecropiaie (Hightower et al 1994;Jan et al 2010;Jaynes et al 1993).…”

“…Transgenic plants showed considerably greater resistance to pathogens (Hightower et al 1994;Jan et al 2010;Jaynes et al 1993;Ohshima et al 1999;Osusky et al 2000;Osusky et al 2004) and parasitic weeds (Radi et al 2006) than to the wild types. Zhang et al (1998) reported that transgenic tobacco expressing human lactoferrin protein demonstrated signi cant delays in developing bacterial wilt symptoms when inoculated with the bacterial pathogen Ralstonia solanacearum.…”

“…Many studies have shown the expression of antimicrobial cationic peptides in plants, e.g., cecropin in tobacco (Hightower et al 1994;Jaynes et al 1993) and tomato (Jan et al 2010), sarcotoxin in tobacco (Ohshima et al 1999) and tomato (Radi et al 2006), MsrA3 in potatoes (Osusky et al 2004), and cecropinmelittin chimeric peptide in potato (Osusky et al 2000). Transgenic plants showed considerably greater resistance to pathogens (Hightower et al 1994;Jan et al 2010;Jaynes et al 1993;Ohshima et al 1999;Osusky et al 2000;Osusky et al 2004) and parasitic weeds (Radi et al 2006) than to the wild types.…”

Recombinant expression of LFchimera antimicrobial peptide in a plant-based expression system and its antimicrobial activity against clinical and phytopathogenic bacteria

“…The secretion of foreign AMPs to apoplast might enhance the peptide-pathogen interaction [68,69], but the respective peptide might be exposed to plant endogenous proteases and be degraded and/or negatively affect the fitness and fertility of transgenic plants [70]. Conversely, several studies have indicated that targeting to the apoplastic space is not always necessary to obtain disease resistance [71].…”

Advances in genetic engineering of marine algae

“…Antimicrobial peptides, which are expressed from only a single heterologous gene, provide a solution for a broad-spectrum ranging from anti-bacteria, -fungi and -protozoan (Farrokhi et al, 2008;Rahnamaeian and Vilcinskas, 2012). These peptides have been successfully integrated and transformed into the nuclei and chloroplasts of higher plants (DeGray et al, 2001, Jan et al, 2010. To prevent the prey from invertebrates, several allelochemicals from cyanobacteria can be introduced and expressed to defend against potential predators and grazers (Berry et al, 2008;Rastogi and Sinha, 2009).…”