Benzoic acid 2-hydroxylase (BA2H) catalyzes the biosynthesis of salicylic acid from benzoic acid. The enzyme has been partially purified and characterized as a soluble protein of 160 kDa. High-efficiency in vivo labeling of salicylic acid with 18O2 suggested that BA2H is an oxygenase that specifically hydroxylates the ortho position of benzoic acid. The enzyme was strongly induced by either tob...

Plant protection based on novel alternative strategies is a major concern in agriculture to sustain pest management. The marc extract of red grape cultivars reveals plant defence inducer properties. Treatment with grape marc extract efficiently induced hypersensitive reaction-like lesions with cell death evidenced by Evans Blue staining of tobacco leaves. Examination of the infiltration zone an...

The N gene of tobacco (Nicotiana tabacum) is a typical resistance (R) gene engendering localization of tobacco mosaic virus (TMV) infection and the elicitation of a hypersensitive necrotic response. The consensus model for R gene-derived resistance is at the level of protein:protein interactions, in which proteins of the pathogen interact with already present receptor-like proteins produced by ...

Purified lipid transfer protein LTP2 from barley applied on tobacco leaves eliminated symptoms caused by infiltration of Pseudomonas syringae pv. tabaci 153. Growth of the pathogen in leaves of transgenic tobacco plants was retarded when compared with non-transformed controls. The percentage of inoculation points that showed necrotic lesions was greatly reduced in transgenic tobacco (17-38% ver...

Protoplasts isolated from tobacco leaves were inoculated with cucumber mosaic virus (CMV) using a method slightly modified from that developed for inoculating tobacco mosaic virus. Multiplication of CMV was demonstrated by staining the protoplasm with fluorescent CMV-antibody, by the electron microscopy of ultrathin sections, and by assaying the infectivity in protoplasts. Seventy to 90% of pro...

Preliminary experiments have shown (1, 2) that, when excised tobacco leaves are cultured in the dark in 0.2 M solutions of potassium succinate or L-malate, a marked stimulation of the formation of citric acid occurs. Furthermore, leaves cultured in succinate increased in their content of malic acid, although culture in L-malate, in the single experiment that has been carried out (2), did not le...

A phosphatase specific for P-glycolate5 was purified from extracts of tobacco leaves until no other phosphatase activity could be demonstrated in the preparation (10). Other plants have now been examined for the presence of this phosphatase. A new isolation procedure for the enzyme was developed because the (NH4) 2SO4 fractionation procedure, which was used with tobacco leaf extracts, inactivat...

and color of the treated area which has been suggeste(l to act as a metabolic siiik (6). The stimulation of both RNA and l)rotein synthesis b) kinetic in tobacco (8) aiid Xmanthinmn (7) leaves has been reported, lanl MIcCalla, 'Moore and Osborne (5) using another kinin, the benzyladenine-C14, have obtained tentative evideence that label was incorporated into RNA although at a very low rate. Wol...

When tobacco plants were treated by injection with nitric oxide (NO)-releasing compounds, the sizes of lesions caused by Tobacco mosaic virus (TMV) on the treated leaves and on upper nontreated leaves were significantly reduced. The reduction in TMV lesion size was caused by NO released from the NO-releasing compounds; the byproduct formed after release of NO from the NO-releasing compound NOC-...