Recombinant Xanthomonas campestris pv. campestris Acyl carrier protein (acpP)
Description
Recombinant Production and Characterization
Recombinant Xcc ACP is typically expressed in Escherichia coli and purified via affinity chromatography. Studies reveal:
Table 1: Biochemical Properties of Recombinant Xcc ACP
Functional Insights from Mutational Studies
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ΔacpP mutants: Exhibit impaired growth in fatty acid-free media and loss of DSF production, confirming ACP’s role in primary metabolism .
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Xanthomonadin biosynthesis: ACP (XanC) is essential for transferring 3-hydroxybenzoate to the polyketide synthase pathway . Deletion of xanC abolishes pigment production.
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Cross-species complementation: Xcc ACP partially rescues E. coli acpP mutants, demonstrating functional conservation .
Regulatory and Pathogenic Implications
ACP is indirectly linked to Xcc virulence through:
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DSF signaling: ACP-bound intermediates are precursors for DSF, which controls biofilm formation and pathogenicity .
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Type III secretion system (T3SS): Fatty acid availability modulates T3SS gene expression via HrpG/HrpX regulators .
Table 2: ACP-Linked Pathways in Xcc Virulence
| Pathway | Associated Proteins | Phenotypic Impact |
|---|---|---|
| DSF synthesis | RpfF, RpfB | Quorum sensing, biofilm |
| Xanthomonadin production | XanA2, XanH (FabG-like) | Antioxidant protection |
| Membrane integrity | FabG1, FabG2 | Cell motility, host invasion |
Biotechnological Applications
Recombinant Xcc ACP is utilized in:
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Enzyme assays: Studying substrate specificity of FAS components (e.g., FabG2’s preference for long-chain 3-oxoacyl-ACPs) .
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Metabolic engineering: Optimizing polyketide pathways for synthetic biology .
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Antimicrobial targeting: Screening inhibitors of acyl-ACP-dependent enzymes .
Unresolved Research Questions
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Post-translational modifications: Impact of phosphopantetheinylation kinetics on ACP function.
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Substrate channeling: How ACP coordinates with dual-function enzymes like RpfF.
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Host interaction dynamics: Role of ACP in modulating plant immune responses during infection.
Product Specs
Target Background
KEGG: xcc:XCC1019
STRING: 190485.XCC1019
