Xanthomonas campestris pv. campestris is the etiological agent of black rot of crucifers, a disease of major economic importance which is a threat to the production of cruciferous crops in many areas of the world [1], During a recent investigation of this patho­ gen for the production of phytotoxic metabolites in liquid culture we observed the biotransformation of certain amino acid constituent...

Adenosine kinase (ADK) is a purine salvage enzyme and a typical housekeeping enzyme in eukaryotes which catalyzes the phosphorylation of adenosine to form AMP. Since prokaryotes synthesize purines de novo and no endogenous ADK activity is detectable in Escherichia coli, ADK has long been considered to be rare in bacteria. To date, only two prokaryotes, both of which are gram-positive bacteria, ...

Plasmodiophora brassicae is an obligate biotroph that causes clubroot, one of the most damaging diseases of crucifers. Differential cultivars and random amplified polymorphic DNA markers were used to assess the extent of genetic diversity among nine single-gall populations of P. brassicae and 37 single-spore isolates (SSI) derived from four of those field samples. Isolates were classified into ...

Foodstuffs of various sorts have been implicated as a cause of goiter for many years. Only by the discovery of Chesney, Clawson and Webster in 1928 that cabbage feeding would result in thyroid enlargement in laboratory animals (1) were these vague hypotheses started on a firm experimental footing, however (for detailed review see Reference 2). Although various articles of diet have been reporte...

Pieris brassicae L. is a serious pest of cultivated crucifers in several parts of the world. Larvae of P. brassicae also feed prolifically on garden nasturtium (Tropaeolum majus L., of the family Tropaeolaceae). Proteolytic digestion was studied in larvae feeding on multiple hosts. Fourth instars were collected from cauliflower fields before transfer onto detached, aerial tissues of selected ho...

Plants contain significant levels of natural phenolic compounds essential for reproduction and growth, as well as defense mechanisms against pathogens. Xanthomonas campestris pv. campestris (Xcc) is the causal agent of crucifers black rot. Here we showed that genes required for the synthesis, utilization, transportation, and degradation of 4-hydroxybenzoate (4-HBA) are present in Xcc. Xcc rapid...

The self-incompatibility response of crucifers is a barrier to fertilization in which arrest of pollen tube development is mediated by allele-specific interactions between polymorphic receptors and ligands encoded by the S-locus haplotype. Activation of stigma-expressed S-locus receptor kinase (SRK) [1] by pollen coat-localized S-locus cysteine-rich (SCR) ligand [2-5] and the resulting rejectio...

The genus Brassica includes several important agricultural and horticultural crops. Their current genome structures were shaped by whole-genome triplication followed by extensive diploidization. The availability of several crucifer genome sequences, especially that of Chinese cabbage (Brassica rapa), enables study of the evolution of the mesohexaploid Brassica genomes from their diploid progeni...

The 35S promoter is a major promoter of the cauliflower mosaic virus that infects crucifers. This promoter is still active when excised from cauliflower mosaic virus and integrated into the nuclear genome of transgenic tobacco. Previous work has shown that the -343 to -46 upstream fragment is responsible for the majority of the 35S promoter strength (Odell, J.T., Nagy, F., and Chua, N.-H. [1985...