Evidence for the breakdown of cecropin B by proteinases in the intercellular fluid of peach leaves

Enhanced resistance to the rice blast fungus Magnaporthe grisea conferred by expression of a cecropin A gene in transgenic rice

“…Moreover, the susceptibility of cecropin B peptides to degradation by endogenous proteases varies from one plant species to another (Mills et al 1994;Owens and Heutte 1997). Together these results reveal that there is no guarantee that a peptide that was effective in one host against one pathogen will be effective in a different host against a different pathogen.…”

“…Failure to obtain pathogen resistance was found to be the consequence of proteolytic degradation of cecropin B peptides by plant proteases present in the intercellular spaces (Mills et al 1994). In this work, two synthetic versions of the cecropin A gene, which were designed for secretion of cecropin A to the apoplastic space or for retention of cecropin A in the ER, were prepared.…”

Antimicrobial peptides

“…103 Short persistence of cecropin B has been ascribed to proteinases in the cytosol mediating proteolysis through an initial endopeptidase cleavage. 104 To put off such an interfering process, Consistently, a Fusarium graminearum mutant deficient in glycosyl ceramide was resistant to both radish RsAFP2 and alfalfa MsDef1 defensins, corroborating the idea that glycosyl ceramide is also the target of MsDef1. 80 On the contrary, pea defensin, Psd1, directs cell cycle impairment and causes Neurospora crassa conidia to undergo endoreduplication.…”

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

“…Plant morphology, plant growth, and yields of fruits and seeds (data not shown) were normal. In most cases, the minimum lethal concentration of cecropin derivatives required for toxicity to plant protoplast, intact cells, and tissues is much higher than that required to kill the bacterial cells (34,38). For example, the lethal concentration of a modified cecropin SB37 on the protoplast of tomatoes (S. lycopersicum cv.…”

“…However, subsequent investigations of these tobacco plants showed that the expression of CB in the plants did not result in accumulation of detectable levels of CB, presumably due to degradation of the peptide by host peptidases (20,34). Therefore, protection of CB from cellular degradation is considered to be vital for the exploitation of its antibacterial activity in transgenic plants.…”