PMID:16483314

From EcoliWiki
Jump to navigation Jump to search
Citation

Okuno, T, Yamanaka, K and Ogura, T (2006) An AAA protease FtsH can initiate proteolysis from internal sites of a model substrate, apo-flavodoxin. Genes Cells 11:261-8

Abstract

Escherichia coli FtsH, which belongs to the AAA (ATPases associated with diverse cellular activities) family, is an ATP-dependent and membrane-bound protease. FtsH degrades misassembled membrane proteins and a subset of cytoplasmic regulatory proteins. It has been proposed that ATP-dependent proteases unfold substrate proteins and initiate a processive proteolysis from either terminus of the substrate polypeptide. We have found that FtsH degrades E. coli apo-flavodoxin (apo-Fld) but not holo-Fld containing non-covalently bound flavin mononucleotide (FMN). A mutant Fld carrying a substitution of Tyr94 to Asp (Fld(YD)) with a lower affinity for FMN was efficiently degraded by FtsH. To elucidate the directionality of Fld(YD) degradation by FtsH, we constructed several Fld(YD) fusion proteins with glutathione S-transferase (GST), green fluorescent protein (GFP), or both GST and GFP. It was found that FtsH was able to initiate degradation of the Fld(YD) moiety even when it was sandwiched by GST and GFP. Evidence indicated that FtsH can initiate proteolysis of GST-Fld(YD)-GFP from the Fld(YD) moiety by translocating an internal loop to the protease chamber in an ATP-dependent manner and that, at least, the proteolysis in the C to N direction proceeds processively.

Links

PubMed Online version:10.1111/j.1365-2443.2006.00940.x

Keywords

ATP-Dependent Proteases; Adenosine Triphosphate/metabolism; Amino Acid Substitution; Apoproteins/genetics; Apoproteins/metabolism; Bacterial Proteins/metabolism; Escherichia coli/enzymology; Escherichia coli Proteins; Flavin Mononucleotide/metabolism; Flavodoxin/genetics; Flavodoxin/metabolism; Glutathione Transferase/genetics; Glutathione Transferase/metabolism; Green Fluorescent Proteins/genetics; Green Fluorescent Proteins/metabolism; Membrane Proteins/metabolism; Models, Molecular; Mutation/genetics; Peptide Hydrolases/metabolism; Recombinant Fusion Proteins/genetics; Recombinant Fusion Proteins/metabolism

Significance

You can help EcoliWiki by summarizing why this paper is useful

Useful Materials and Methods

You can help Ecoliwiki by describing the useful materials (strains, plasmids, antibodies, etc) described in this paper.

Annotations

<annotationlinks/>

EcoliWiki Links

Add links to pages that link here (e.g. gene, product, method pages)

References

See Help:References for how to manage references in EcoliWiki.