User:Adam Meade/Sandbox 1: Difference between revisions

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'''Background Information'''

Iron is potentially toxic to cells, as in the presence of oxygen, Fenton reactions can produce reactive oxygen species that can destroy essential biomolecules. Balancing the amount of iron in the cell is important and this importance is apparent from the elaborate mechanisms cells devote to iron homeostasis. Part of this iron balancing is achieved by regulation of iron import. The genes required for ferric citrate transport in ''Rhodobacter sphaeroides'' form a cluster in the order fecI-fecR-fecABCDE, encoding a specialized sigma factor and a putative anti-sigma factor that together are responsible for regulated transcription of the ferric citrate transport operon, encoding an ABC-type ferric citrate transporter. In ''Escherichia coli'', fecI transcription is regulated by Fur in response to iron availability; in ''Bradyrhizobium japonicum'', as well as ''R. sphaeroides'', which both lack Fur, fecI transcription is thought to be regulated by another iron-responsive DNA binding protein, Irr, or the iron response regulator protein. <ref>1) Hamza I, S. Chauhan, R. Hassett, MR O'Brian, 1998. <u>The bacterial irr protein is required for coordination of heme biosynthesis with iron availability.</u>. Journal of Biological Chemistry 34:21669-74.</ref>

Iron is potentially toxic to cells, as in the presence of oxygen, Fenton reactions can produce reactive oxygen species that can destroy essential biomolecules. Balancing the amount of iron in the cell is important and this importance is apparent from the elaborate mechanisms cells devote to iron homeostasis. Part of this iron balancing is achieved by regulation of iron import. The genes required for ferric citrate transport in ''Rhodobacter sphaeroides'' form a cluster in the order fecI-fecR-fecABCDE, encoding a specialized sigma factor and a putative anti-sigma factor that together are responsible for regulated transcription of the ferric citrate transport operon, encoding an ABC-type ferric citrate transporter. In ''Escherichia coli'', ''fecI'' transcription is regulated by Fur in response to iron availability; in ''Bradyrhizobium japonicum'', as well as ''R. sphaeroides'', which both lack Fur, ''fecI'' transcription is thought to be regulated by another iron-responsive DNA binding protein, Irr, or the iron response regulator protein. <ref>1) Hamza I, S. Chauhan, R. Hassett, MR O'Brian, 1998. <u>The bacterial irr protein is required for coordination of heme biosynthesis with iron availability.</u>. Journal of Biological Chemistry 34:21669-74.</ref>

Revision as of 00:33, 19 April 2009 view source Adam Meade (talk \| contribs) 36 edits No edit summary ← Older edit		Revision as of 00:34, 19 April 2009 view source Adam Meade (talk \| contribs) 36 edits No edit summary Newer edit →
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	'''Background Information'''		'''Background Information'''

	Iron is potentially toxic to cells, as in the presence of oxygen, Fenton reactions can produce reactive oxygen species that can destroy essential biomolecules. Balancing the amount of iron in the cell is important and this importance is apparent from the elaborate mechanisms cells devote to iron homeostasis. Part of this iron balancing is achieved by regulation of iron import. The genes required for ferric citrate transport in ''Rhodobacter sphaeroides'' form a cluster in the order fecI-fecR-fecABCDE, encoding a specialized sigma factor and a putative anti-sigma factor that together are responsible for regulated transcription of the ferric citrate transport operon, encoding an ABC-type ferric citrate transporter. In ''Escherichia coli'', fecI transcription is regulated by Fur in response to iron availability; in ''Bradyrhizobium japonicum'', as well as ''R. sphaeroides'', which both lack Fur, fecI transcription is thought to be regulated by another iron-responsive DNA binding protein, Irr, or the iron response regulator protein. <ref>1) Hamza I, S. Chauhan, R. Hassett, MR O'Brian, 1998. <u>The bacterial irr protein is required for coordination of heme biosynthesis with iron availability.</u>. Journal of Biological Chemistry 34:21669-74.</ref>		Iron is potentially toxic to cells, as in the presence of oxygen, Fenton reactions can produce reactive oxygen species that can destroy essential biomolecules. Balancing the amount of iron in the cell is important and this importance is apparent from the elaborate mechanisms cells devote to iron homeostasis. Part of this iron balancing is achieved by regulation of iron import. The genes required for ferric citrate transport in ''Rhodobacter sphaeroides'' form a cluster in the order fecI-fecR-fecABCDE, encoding a specialized sigma factor and a putative anti-sigma factor that together are responsible for regulated transcription of the ferric citrate transport operon, encoding an ABC-type ferric citrate transporter. In ''Escherichia coli'', ''fecI'' transcription is regulated by Fur in response to iron availability; in ''Bradyrhizobium japonicum'', as well as ''R. sphaeroides'', which both lack Fur, ''fecI'' transcription is thought to be regulated by another iron-responsive DNA binding protein, Irr, or the iron response regulator protein. <ref>1) Hamza I, S. Chauhan, R. Hassett, MR O'Brian, 1998. <u>The bacterial irr protein is required for coordination of heme biosynthesis with iron availability.</u>. Journal of Biological Chemistry 34:21669-74.</ref>