Disease relevance of Pyrrolnitrin

• Pseudomonas fluorescens Pf-5, a rhizosphere-inhabiting bacterium that suppresses several soilborne pathogens of plants, produces the antibiotics pyrrolnitrin, pyoluteorin, and 2,4-diacetylphloroglucinol [1].
• Pyrrolnitrin is a secondary metabolite of Pseudomonas and Burkholderia sp. strains with strong antifungal activity [2].
• Transfer of the four gene cluster to E. coli resulted in the production of pyrrolnitrin by this organism, thereby demonstrating that the four genes are sufficient for the production of this metabolite and represent all of the genes required to encode the pathway for pyrrolnitrin biosynthesis [2].
• Contact dermatitis from pyrrolnitrin [3].
• Among Gram-positive bacteria, pyrrolnitrin was most active against certain Streptomyces species, especially S. antibioticus, which has not previously been described in the literature [4].

High impact information on Pyrrolnitrin

• A plasmid containing the cloned wild-type rpoS gene restored pyrrolnitrin production and stress tolerance to the RpoS- mutant of Pf-5 [1].
• The enzyme showed a limited range of substrate specificity and catalyzed the conversion of aminopyrrolnitrin into pyrrolnitrin with K(m) = 191 microM and k(cat) = 6.8 min(-1) [5].
• The first bacterial chloroperoxidase that is capable of catalyzing the chlorination of indole to 7-chloroindole was detected in Pseudomonas pyrrocinia ATCC 15958, a bacterium that produces the antifungal antibiotic pyrrolnitrin (Wiesner, W., van Pée, K.H., and Lingens, F. (1986) FEBS Lett. 209, 321-324) [6].
• The synthesis, anti-Candida activity, and quantitative structure-activity relationship (QSAR) studies of a series of 2,4-dichlorobenzylimidazole derivatives having a phenylpyrrole moiety (related to the antibiotic pyrrolnitrin) in the alpha-position are reported [7].
• Well-characterized antibiotics with biocontrol properties include phenazines, 2,4-diacetylphloroglucinol, pyoluteorin, pyrrolnitrin, lipopeptides, and hydrogen cyanide [8].

Chemical compound and disease context of Pyrrolnitrin

• METHODS AND RESULTS: Pseudomonas fluorescens CHA0 produces the three antifungal metabolites 2,4-diacetylphloroglucinol (DAPG), pyoluteorin (PLT) and pyrrolnitrin (PRN) [9].
• Metabolism of tryptophan by Pseudomonas aureofaciens and its relationship to pyrrolnitrin biosynthesis [10].
• Although all Pseudomonas strains exhibited catalase activity, the enzyme isolated from P. pyrrolnitrica was named catalase-bromoperoxidase, because it catalyzed not only a catalase reaction, but also the bromination of monochlorodimedone [11].

Biological context of Pyrrolnitrin

• Deletion mutations in any of the four genes resulted in a pyrrolnitrin-nonproducing phenotype [2].
• Pseudomonas fluorescens BL915 has been reported to produce pyrrolnitrin and to be an effective biocontrol agent for this pathogen [2].
• Marker-exchange mutagenesis of this DNA with Tn5 revealed the presence of a 6.2-kb region that contains genes required for the synthesis of pyrrolnitrin [2].
• The nucleotide sequence of the 6.2-kb region was determined and found to contain a cluster of four genes that are required for the production of pyrrolnitrin [2].
• In each case, the appropriate tac promoter-pyrrolnitrin gene fusion was shown to complement the pyrrolnitrin-negative phenotype of the corresponding deletion mutant [2].

Anatomical context of Pyrrolnitrin

• 4. Analysis of pyrrolnitrin inhibition curves, respiration studies, ESR spectra, and the steady-state level of reduction of cytochrome b in the presence and absence of the drug shows that pyrrolnitrin acts to inhibit electron transport in Neurospora mitochondria at multiple sites in the region between ubiquinone and cytochrome b [12].

Associations of Pyrrolnitrin with other chemical compounds

• The drug pyrrolnitrin [3-chloro-4-(2'-nitro-3'-chlorphenyl)pyrrole] is an effective inhibitor of both NADH-supported and succinate-supported electron transport in Neurospora [12].
• The capacity of tegobetain, pyrrolnitrin, tolcyclate and chlorquinaldol to induce delayed-type contact sensitization was studied in guinea pigs in 2 series of tests using the method of Magnusson & Kligman and the authors' modification of the wholly intradermal Draize technique [13].
• Spectroscopic data (HPLC, MS and NMR) confirmed that the compound was pyrrolnitrin [3-chloro-4-(2'-nitro-3'-chloro-phenyl) pyrrole] [4].
• The mechanism of action of ambruticin thus appears to be the same as that of the phenylpyrroles, e.g., pyrrolnitrin, viz., interference with osmoregulation [14].
• The potential of postharvest dip treatments with fludioxonil (FLU) (a synthetic analogue of the bacterial metabolite of pyrrolnitrin), in controlling postharvest decay caused by Penicillium digitatum and Penicillium italicum of citrus fruit was investigated in comparison with the conventional fungicide imazalil (IMZ) [15].

Gene context of Pyrrolnitrin

• The prnD gene product catalyzes the oxidation of the amino group of aminopyrrolnitrin to a nitro group to form pyrrolnitrin [16].
• With the exception of the prnA gene from M. fulvus59% similar among the strains, indicating that the biochemical pathway for pyrrolnitrin biosynthesis is highly conserved [17].
• Spontaneous pleiotropic mutants of P. fluorescens strain BL915 which fail to synthesize antifungal factors such as chitinase, cyanide, and pyrrolnitrin and exhibit altered colony morphology were isolated [18].

Analytical, diagnostic and therapeutic context of Pyrrolnitrin

• Isotope labeling experiments with (18)O(2) and H(2)(18)O suggested that the oxygen atoms in the pyrrolnitrin product are derived exclusively from molecular oxygen [5].
• Pyrrolnitrin, aminopyrrolnitrin, and monochloroaminopyrrolnitrin were isolated from J82 and identified by using thin-layer chromatography, high-performance liquid chromatography, and electron impact-mass, UV, and infrared spectroscopy [19].
• The antagonist from RJ3 has been identified as the antifungal compound pyrrolnitrin after purification by HPLC and characterization by UV, IR, NMR, and mass spectroscopy [20].
• Release of surface antigens of Candida albicans after treatment with pyrrolnitrin [21].

References