These Five Slides About examine the structure and function of the iron binding and transport protein transferrin. Students learn that transferrin also acts as an iron buffer and as a potential antimicrobial agent. The structure of the protein is explored in detail; it consists of a single polypeptide (80kDa) folded into two lobes, each of which can bind a single iron in a high affinity region. Changes in the protein as a result of iron uptake is discussed. The iron binding region and the requirement of a bidentate synergistic anion (carbonate) are examined. Finally, the relationship between transferrin and iron-overload is presented.
After examining these slides, students should be able to:
- Discuss the various biological functions of the transferrins and its importance in these roles.
- Describe the overall structure of the protein.
- Describe the iron binding sites, including the importance of the synergistic anion.
- Discuss the importance of this protein in the treatment of iron overload disorders.
These slides can be used at any point that the protein transferrin is discussed. They can be used either for straight lecture or as part of an in-class discussion. I have used them in class as an introduction to the protein prior to assignment of an article from the primary literature. I also use them for students who who are interested in doing undergraduate research with me.
Although I have not yet tried this, I am planning on using these slides while at the same time having students access the crystal structure of ovotransferrin (1OVT) on the PDB. The ability to "rotate" the protein may make its overall structure and the iron binding sites easier to discern.
To date I have used these slides only as an introduction to transferrin, both in class and as part of a research project. Evaluation was based on the understanding of these topics as applied to readings from the primary literature, through discussion, and through inclusion of these background topics in research reports. As described in the implementation notes I intend to connect these slides to an exercise involving the PDB. A more direct means of evaluation should be obtained at that point.
Although no formal evaluation of the effectiveness of these slides has been undertaken, my experience is that they are a good introduction to the topic---students refer to them correctly in discussions and I find that they understand this background enough to attack articles from the primary literature successfully.