Erythrin

Glazer, A.N. and Hixson, C.S., Subunit structure and chromophore composition of rhodophytan phycoerythrins Porphyridium cruentum B-phycoerythrin and b-phyco-erythrin, J. Biol. Chem., 252, 32, 1977. 

Ko FN, Chen IS, Wu SJ, Lee LG, Haung TF, Teng CM. Antiplatelet effects of chel-erythrine chloride isolated from Zanthoxylum simulans. Biochim Biophys Acta 1990 1052 360-365. 

Interestingly an erythrin, without the C-terminal rubredoxin domain is found, perhaps appropriately in Cyanophora paradoxa, where, like the rubrerythrins, its function is unknown. 

Klotz, I.M., and Keresztes-Nagy, S. (1962) Dissociation of proteins into subunits by succinylation haem-erythrin. Nature (London) 195, 900. 

The high molar absorptivities and quantum yields of the large protein fluorophore phycoerythrin (240,000 Da) have been exploited in energy transfer assays. Phyco-erythrin has been used as both donor and acceptor, with several bound antigen molecules per phycoerythrin molecule/86,94) The usefulness of BPE is indicated in competitive assays for human IgG that use fluorescein-labeled antibody as donor to... 

Figure 14.18. Diagrammatic representation of a phenytoin fluorescence energy transfer fiber optic sensor, as described in the text. -< = Antibody-Texas Red P = unlabeled phenytoin P = phenytoin-b-phyco-erythrin. (Adapted from Ref, 119.)...

Jin S, Kurtz DM, Liu ZJ, Rose J, Wang BC (2002) X-ray crystal structures of reduced rubr-erythrin and its azide adduct a structure-based mechanism for a non-heme diiron peroxidase. J Am Chem Soc 124 9845-9855... 

The analysis of a complex population of cells may call for the identification of the cells of interest with one MAb, and quantitation of antigen expression on these cells with a second antibody. The choice of fluorochrome for each purpose may be influenced by relative levels of expression of the markers involved, as well as the factors referred to above. There is a degree of spectral overlap between fluorochromes, and this may make sensitive quantitation of a low level antigen difficult in the presence of high level labeling of the first antibody used for cell identification. This can be mitigated to some extent by selection of the more sensitive fluorochrome (e.g., phyco-erythrin) for the low level quantitation. In any event, quantitative analysis requires careful adjustment of spectral overlap an adjustment procedure for multiple fluorochromes appears in Chapter 34, and quantitative adjustment of compensation is illustrated in Section 3.4. 

Two erythrine alkaloids, erythristemine (46)80 and erythrinine (47),81 contain 4-methoxy and 4-hydroxy groups, respectively, in a tetra-hydroisoquinoline ring, albeit highly substituted. 

Certain spectroscopic properties of the oxidized iron center were characterized at an early stage (77) and compared with those of hem-erythrin, which was at that time the best-characterized protein with a diferric p.-oxo-bridged iron center. A prominent light absorption in the 300-400 nm region, with partly resolved bands around 320 and 360 nm (e around 10,000 cm ) and two weak bands (e around... 

Bloodroot Sanguinaria canadensis) is also mentioned as another remedy for cancer. It was used in London hospitals in the nineteenth century by a doctor who had learned of it from Indians living near Lake Superior. It was confirmed in the laboratory that alkaloids derived from bloodroot, for example, sanguarine and chel-erythrine, produced tumor reduction in mice. 

For purification of PBMC subsets, cells are isolated, washed twice, resuspended in PBS at 1 X 10 cells/mL, incubated at room temperature for 30min with phyco-erythrin labeled primary antibodies (mouse-antihuman CD20, CD4, CDS, or CD14), and washed twice with PBS. The PBMC is resuspended in PBS at 1 x 10 cells/mL, incubated at 4°C for 30min and labeled with goat-anti-mouse IgG, and washed and resuspended in 0.5mL of PBS. The labeled and unlabeled PBMC are separated, resuspended in assay medium, divided into 0.1-mL aliquots onto a 96-well round-bottom plate, and incubated overnight. To the wells, DXM is added and incubated for another 24h to isolate RNA. 

Phenolic oxidative coupling of the diphenolic bis(phenethyl)amine 101 to the 11-membered ring structure (102) controls the formation of the isoquinoline system at the stage of iminium salt 103 and explains the 7,8-substitution pattern in the isoquinoline part of cularine alkaloids (40, 63). However, to date, no such precursors have been isolated from natural sources. Moreover, phenolic oxidative coupling of synthetic precursors such as 101, using a variety of one electron oxidation reagents, gives rise to polymerized compounds or products with the skeleton of erythrine alkaloids (104) (68). 

ORAC AAPH induced oxidation of j3-phyco-erythrin, fluorescence decay curve Non specific substrate. Protection of photoreceptor not equal to protein protection Delange and GlazCT (1989), Glazer (1990) Cao etal. (1993)... 

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