Recombinant Escherichia coli ATP-binding/permease protein CydD (cydD)
Description
Functional Role in Bacterial Physiology
CydD functions as part of the CydDC transporter, which has two primary roles:
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Thiol Export: Mediates ATP-dependent transport of cysteine and glutathione (GSH) to the periplasm, critical for cytochrome bd oxidase assembly .
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Heme Regulation: Binds heme b and modulates ATPase activity, suggesting a regulatory role in redox homeostasis .
Key Functional Data:
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Basal ATPase activity of purified CydDC: ~100 nmol Pi/min/mg .
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Thiol compounds (e.g., cysteine) stimulate ATPase activity 3-fold; heme further enhances this activity but inhibits it at high concentrations .
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Loss of CydD abolishes cytochrome bd assembly, confirmed by UV-Vis spectroscopy and oxygen consumption assays .
Complementation Studies
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Cytochrome Restoration: Recombinant CydDC partially restores cytochrome bd assembly in cydD mutant strains, evidenced by regained heme d absorption at 650 nm .
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Redox Homeostasis: cydD mutants exhibit defective periplasmic cytochrome c assembly, implicating CydDC in maintaining periplasmic redox balance .
Therapeutic Implications
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Antibiotic Targets: Cytochrome bd (dependent on CydDC) is a target for antimicrobials like aurachin D, highlighting CydD’s pharmacological relevance .
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Oxidative Stress: cydD mutants show heightened sensitivity to nitric oxide (NO), suggesting roles in pathogen resilience .
Unresolved Questions and Future Directions
Product Specs
Note: We prioritize shipping the format currently in stock. However, if you have specific format requirements, please indicate them during order placement. We will fulfill your request whenever possible.
Note: All our proteins are shipped with standard blue ice packs. If you require dry ice shipping, please communicate with us in advance, as additional fees will apply.
Generally, the shelf life of liquid form is 6 months at -20°C/-80°C. The shelf life of lyophilized form is 12 months at -20°C/-80°C.
Target Background
- CydDC is the first prokaryotic GSH transporter, and it exports reductant to the periplasm PMID: 16040611
KEGG: ecj:JW0870
STRING: 316385.ECDH10B_0957
