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The role of RodAp-conserved cysteine residues in the Aspergillus fumigatus conidial surface organization

ABSTRACT: Immune inertness of Aspergillus fumigatus conidia, an airborne fungal pathogen, is attributed to its surface rodlet-layer made up of RodAp, a protein belonging to the hydrophobin family, characterized by eight conserved cysteine residues forming four disulfide bonding. Earlier, we showed that the conserved cysteine residue point (ccrp) mutations result in conidia devoid of the rodlet-layer. Here we extended our study in comparing ccrp-mutation with RODA deletion on their mutant conidial surface organization, permeability and immunoreactivity. Western blot using anti-RodAp antibodies indicated the absence of RodAp in the cytoplasm of ccrp-mutant conidia. Upon immunolabelling, ccrp-mutant conidia showed strong positivity for -(1,3)-glucan and weak positivity for -(1,3)-glucan, which was reverse in ∆rodA conidia, and the parental strain conidia were negative; all of their conidial cell wall permeability was similar. Proteomic analyses of the conidial surface exposed proteins of the ccrp-mutants, although lower in number, showed more similarities with the parental strain, but a significant difference with the RODA deletion mutant strain. Further, ccrp-mutant conidia are less immunostimulatory compared to ∆rodA conidia. Together, our data suggest that (i) the conserved cysteine residues are essential for the trafficking of RodAp and the organization of rodlet-layer on the conidial surface, and (ii) point-mutation could be an alternative strategy to study the proteins involved in the organization of fungal cell wall.

INSTRUMENT(S): Q Exactive HF

ORGANISM(S): Neosartorya Fumigata (aspergillus Fumigatus)

SUBMITTER: Thomas Krüger

LAB HEAD: Axel A. Brakhage

PROVIDER: PXD020136 | Pride | 2021-02-18

REPOSITORIES: Pride

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			Action	DRS
	AF1-1-a.raw	Raw
	AF1-1-b.raw	Raw
	AF1-1-c.raw	Raw
	AF1-1.fasta	Fasta
	AF1-1.mgf	Mgf

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The role of RodAp-conserved cysteine residues in the Aspergillus fumigatus conidial surface organization

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