A Cytochrome b561 with Ferric Reductase Activity from the Parasitic Blood Fluke, Schistosoma japonicum

作者：Glanfield Amber^*; McManus Donald P; Smyth Danielle J; Lovas Erica M; Loukas Alex; Gobert Geoffrey N; Jones Malcolm K

来源：PLoS Neglected Tropical Diseases, 2010, 4(11): e884.

DOI：10.1371/journal.pntd.0000884

Background: Iron has an integral role in numerous cellular reactions and is required by virtually all organisms. In physiological conditions, iron is abundant in a largely insoluble ferric state. Ferric reductases are an essential component of iron uptake by cells, reducing iron to the soluble ferrous form. Cytochromes b561 (cyts-b561) are a family of ascorbate reducing transmembrane proteins found in most eukaryotic cells. The identification of the ferric reductase duodenal cytochrome b (dcytb) and recent observations that other cyts-b561 may be involved in iron metabolism have opened novel perspectives for elucidating their physiological function.
Methodology/Principal Findings: Here we have identified a new member of the cytochrome b561 (Sjcytb561) family in the pathogenic blood fluke Schistosoma japonicum that localises to the outer surface of this parasitic trematode. Heterologous expression of recombinant Sjcyt-b561 in a Saccharomyces cerevisiae mutant strain that lacks plasma membrane ferrireductase activity demonstrated that the molecule could rescue ferric reductase activity in the yeast.
Significance/Conclusions: This finding of a new member of the cytochrome b561 family further supports the notion that a ferric reductase function is likely for other members of this protein family. Additionally, the localisation of Sjcytb561 in the surface epithelium of these blood-dwelling schistosomes contributes further to our knowledge concerning nutrient acquisition in these parasites and may provide novel targets for therapeutic intervention.

• 出版日期2010-11
• 单位河北医科大学