Disease relevance of C08440

• The crystal structure is reported at 1.8 A resolution of Escherichia coli ornithine transcarbamoylase in complex with the active derivative of phaseolotoxin from Pseudomonas syringae pv. phaseolicola, N(delta)-(N'-sulfodiaminophosphinyl)-l-ornithine [1].
• The inhibition of ornithine transcarbamoylase from Escherichia coli W by phaseolotoxin [2].
• Phaseolotoxin transport in Escherichia coli and Salmonella typhimurium via the oligopeptide permease [3].

High impact information on C08440

• Multiple copies of a DNA sequence from Pseudomonas syringae pathovar phaseolicola abolish thermoregulation of phaseolotoxin production [4].
• We propose that the binding protein is a repressor which is 'titrated' by this fragment when it is present in the cell on a multiple copy plasmid, thus allowing expression of phaseolotoxin genes [4].
• Under steady-state conditions phaseolotoxin inhibition was reversible and exhibited mixed kinetics with respect to carbamoyl phosphate [2].
• We sequenced the region around argK and amtA in P. syringae pv. phaseolicola NPS3121 to determine the limits of the putative phaseolotoxin gene cluster and to determine the transcriptional pattern of the genes comprising it [5].
• Functional Characterization of the Gene Cluster from Pseudomonas syringae pv. phaseolicola NPS3121 Involved in Synthesis of Phaseolotoxin [5].

Biological context of C08440

• The isolates were classified as race 5, and their analysis revealed that they do not carry the argK-tox gene cluster involved in the biosynthesis of the phaseolotoxin [6].
• Pseudomonas syringae pv. phaseolicola genomic clones harboring heterologous DNA sequences suppress the same phaseolotoxin-deficient mutants [7].
• Genes involved in the production of phaseolotoxin by Pseudomonas syringae pv. "phaseolicola" NPS3121 were identified by Tn5 mutagenesis and cosmid cloning [8].
• We confirmed that the latter is also resistant to phaseolotoxin and possesses ROCT, and we compared the two pathovars by using sequence data of the ROCT gene and the intergenic spacer region located between the 16S and 23S rRNA genes (16S-23S spacer region) as an index [9].
• The phtE locus in the phaseolotoxin gene cluster has ORFs with homologies to genes encoding amino acid transferases, the AraC family of transcriptional factors, and fatty acid desaturases [10].

Associations of C08440 with other chemical compounds

• These data suggest that ORF3 encodes a protein involved in the biosynthesis of ornithine, a constituent of phaseolotoxin [10].
• Furthermore, expression of the amtA and argK genes and phaseolotoxin production occurs at 18 degrees C but not at 28 degrees C. An amidinotransferase insertion mutant was obtained that lost the capacity to synthesize homoarginine and phaseolotoxin [11].

Gene context of C08440

• ROCT is encoded by argK, which is expressed coordinately with phaseolotoxin synthesis at 18 degrees C. To investigate the regulatory mechanisms of this system, null mutants were constructed for argK, argF (encoding the phaseolotoxin-sensitive OCTase [SOCT]), and amtA (encoding an amidinotransferase involved in phaseolotoxin synthesis) [12].
• Phaseolotoxin [(N delta-phosphosulfamyl)ornithylalanylhomoarginine], a phytotoxic tripeptide produced by Pseudomonas syringae pv. phaseolicola that inhibits ornithine carbamoyltransferase, is transported into Escherichia coli and Salmonella typhimurium via the oligopeptide transport system (Opp) [3].
• However, production of the phaseolotoxin-resistant OCTase encoded by argK, synthesis of phaseolotoxin, and infectivity for bean pods occur independently of the ArgR protein [13].
• Inhibition of ornithine carbamoyltransferase from Pseudomonas syringae pv. syringae W50 by phaseolotoxin [14].
• The ornithine carbamoyltransferase of plant extracts was inhibited by phaseolotoxin [15].

Analytical, diagnostic and therapeutic context of C08440

• These Tox(-) isolates appear to lack the entire DNA region for the biosynthesis of phaseolotoxin (argK-tox gene cluster), as shown by PCR amplification and DNA hybridization using DNA sequences specific for separated genes of this cluster [16].

References