Genes encoding lysozyme (T4L) from T4 bacteriophage and attacin E (attE) from Hyalophora cecropia were used, either singly or in combination, to construct plant binary vectors, pLDB15, p35SAMVT4, and pPin2Att35SAMVT4, respectively, for Agrobacterium-mediated transformation of `Galaxy' apple, to enhance resistance to Erwinia amylovora. In these plasmids, the T4L gene was controlled by the cauliflower mosaic virus 35S promoter with duplicated upstream domain and the untranslated leader sequence of alfalfa mosaic virus RNA 4, and the attE gene was controlled by the potato proteinase inhibitor II (Pin2) promoter. All transgenic lines were screened by polymerase chain reaction (PCR) for T4L and attE genes, and a double-antibody sandwich enzyme-linked immunosorbent assay for neomycin phosphotransferase II. Amplification of T4L and attE genes was observed in reverse transcriptase-PCR, indicating that these genes were transcribed in all tested transgenic lines containing each gene. The attacin protein was detected in all attE transgenic lines. The expression of attE under the Pin2 promoter was constitutive but higher levels of expression were observed after mechanical wounding. Some T4L or attE transgenic lines had significant disease reduction compared to nontransgenic `Galaxy'. However, transgenic lines containing both attE and T4L genes were not significantly more resistant than nontransgenic `Galaxy', indicating that there was no in planta synergy between attE and T4L with respect to resistance to E. amylovora.
Kisung Ko, John L. Norelli, Jean-Paul Reynoird, Herb S. Aldwinckle, and Susan K. Brown
Hidemi Izumi, Tota Kiba, Akio Hikone, Hirohisa Hirano, and Shigeji Kuwana
Effect of electrolyzed water on total microbial count of several fresh-cut vegetables was evaluated. Electrolyzed water (pH 6.5), containing 20 ppm available chlorine, was produced by electrolysis of salt solution using an electrolyzed neutral water generator, Ameni Clean (Matsushita Seiko Co. Ltd., Osaka, Japan). Fresh-cut vegetables, including carrot slices, chopped bell peppers, trimmed spinach leaves, shredded Japanese radish, and diced potatoes, were treated with electrolyzed water by dipping, rinsing, or bubbling (immersion and flush with air at 25 L/min) for 3 min and then rinsed with running tap water for 1 min. These treatments reduced the total microbial count by about 1 to 2 log units on tissue surface and inside of all vegetables relative to nontreated samples. Since rinsing with tap water also reduced the microbial count by about 1 log unit, the bubbling treatment was the only effective treatment in reducing bacteria on the surface of fresh-cut Japanese radish and potatoes when compared with water-rinsed controls. When samples were not rinsed with tap water after treatment, the microbicidal effect of electrolyzed water was noted on tissue surface of all vegetables even if relative to water-rinsed controls. Electrolyzed water did not affect the tissue pH ranging from 5.7 to 6.1, surface color, and taste of any fresh-cut.
Ed Stover, Richard R. Stange Jr., T. Gregory McCollum, Jesse Jaynes, Michael Irey, and Erik Mirkov
.F. 2002 In vitro microbicidal activities of cecropin peptides D2A21 and D4E1 and gel formulations containing 0.1 to 2% D2A21 against Chlamydia trachomatis Antimicrob. Agents Chemother. 46 34 41 10.1128/AAC.46.1.34-41.2002 Bastianel, C. Garnier-Semancik, M