Isolation and analysis of a gene bbe1 encoding the berberine bridge enzyme from the California poppy Eschscholzia californica.

A genomic clone, bbe1 was isolated that encodes the methyl jasmonate-inducible berberine bridge enzyme of antimicrobial benzophenanthridine alkaloid biosynthesis in the California poppy Eschscholzia californica. Genomic DNA gel blot analysis indicates that two genes are present in the E. californica genome that code for the berberine bridge enzyme reading frame. Each coding region is apparently preceeded by a unique promoter sequence. The bbe1 gene contains no introns and one transcriptional start site. A 41 nucleotide region between -496 and -455 of the 5'-flanking region appears to be essential for promoter activity in E. californica. The promoter displayed an unexpectedly high species specificity, being active in only E. californica and Thalictrum bulgaricum, out of 28 cell suspension cultures tested.

Cloning and heterologous expression of NADPH-cytochrome P450 reductases from the Papaveraceae.

Cytochrome P450 reductase was purified to homogeneity from cell suspension cultures of the opium poppy Papaver somniferum, the enzyme was characterized (K(m) cytochrome c, 8.3 microM; K(m) NADPH, 4.2 microM; pH optimum, 8.0; M(r), 80 kDa), and the amino acid sequence of internal peptides was determined. Partial cDNA clones from P. somniferum and from Eschscholzia californica (California poppy) were then generated using the polymerase chain reaction and were used as hybridization probes to isolate full-length cDNAs. The Papaver and Eschscholzia cytochrome P450 reductases are 63% identical at the nucleotide level and 69% identical at the amino acid level. SDS-PAGE of the purified native P. somniferum enzyme as well as genomic DNA gel blot analysis indicate that two cytochrome P450 reductase isoforms are present in each species. This evidence is also supported by translation of nucleotide sequences obtained from the PCR-generated partial cDNAs and the full-length cDNAs isolated from lambda libraries. The Papaver and Eschscholzia cytochrome P450 reductases were functionally expressed in the yeast Saccharomyces cerevisiae and in the insect cell culture Spodoptera frugiperda Sf9. Coexpression of cytochrome P450 reductase with the C-O phenol coupling cytochrome P450 of bisbenzylisoquinoline alkaloid biosynthesis in Berberis stolonifera, berbamunine synthase (CYP80A1), in insect cell culture resulted in an alteration of the product profile as compared to that obtained by expression of berbamunine synthase in the absence of plant reductase.

The schistosomulicidal activity and the production of IL-1 and TNF-alpha by peritoneal macrophages from infected mice and their potentiation by muramyl tripeptide-phosphatidyl ethanolamine (MTP-PE) treatment.

Production of TNF-alpha and IL-1 by adherent peritoneal exudate macrophages (APEM) was monitored for 20 weeks in Schistosoma mansoni infected mice in comparison to their schistosomulicidal activity. LPS-triggered IL-1 and TNF-alpha production by APEM peaked 10 weeks post infection (p.i.) and declined thereafter. The schistosomulicidal activity of APEM also peaked after 10 weeks but remained elevated thereafter. Infected mice were also treated with the immunostimulator liposomal muramyl tripeptide-phosphatidyl ethanolamine (MTP-PE) 6 or 10 weeks p.i., and their APEM were tested 4 weeks later. APEM from such treated animals showed elevated IL-1 and TNF-alpha production when treatment commenced 6 weeks p.i., while their schistosomulicidal activity increased when treatment commenced either 6 or 10 weeks p.i. The L-arginine inhibitor, NG monomethyl arginine, markedly inhibited the schistosomulicidal activity but not the IL-1 and TNF-alpha production of APEM. Our results show that monokine production increases during the acute phase of infection and declines during its chronic phase, while macrophage schistosomulicidal activity remains constant throughout. Furthermore, TNF-alpha or IL-1 may play a minor role in APEM mediated killing of schistosomula.