Aspergillus fumigatus Af293 and Neosartorya fumigata (strain CEA10 / CBS 144.89 / FGSC A1163) (Aspergillus fumigatus) Siderophore esterase IroE-like AfEstB
Comment
(from UniProtKB) Displays specific TAFC esterase activity but does not hydrolyze fusarinine C, which has the same core structure as TAFC. Hydrolysis optimizes but is not essential for TAFC-mediated iron uptake.Both extra- and intracellular siderophores have been shown to be crucial for the virulence. Subsequent to chelation of iron and uptake, FsC and TAFC are hydrolyzed and the iron is transferred to the metabolism or to the intracellular siderophore ferricrocin (FC) for transport and storage of iron. Hydrolyzes both TAFC and DF-TAFC with equal efficiencies, suggesting that its function might not be restricted to the release of iron from the siderophore but might also include the degradation of the iron-free chelator to protect cells Kargl et al.
(Below N is a link to NCBI taxonomic web page and E link to ESTHER at designed phylum.) > cellular organisms: NE > Eukaryota: NE > Opisthokonta: NE > Fungi: NE > Dikarya: NE > Ascomycota: NE > saccharomyceta: NE > Pezizomycotina: NE > leotiomyceta: NE > Eurotiomycetes: NE > Eurotiomycetidae: NE > Eurotiales: NE > Aspergillaceae: NE > Aspergillus: NE > Aspergillus fumigatus: NE
Warning: This entry is a compilation of different species or line or strain with more than 90% amino acide identity. You can retrieve all strain data
(Below N is a link to NCBI taxonomic web page and E link to ESTHER at designed phylum.) Aspergillus fumigatus Af293: N, E.
Aspergillus fumigatus A1163: N, E.
LegendThis sequence has been compared to family alignement (MSA) red => minority aminoacid blue => majority aminoacid color intensity => conservation rate title => sequence position(MSA position)aminoacid rate Catalytic site Catalytic site in the MSA MGDRPTPVPLPNSEQFYLENDRGEPYLIQVSWPLHWEDKQTGRGPLPIIY IVDGNALFLTATEAAWRRAAASHFAGGGIIVAIGYPLKGKLYDARRRSFD LTPPTACAPVGYGGADVFLDFIENSVRPAVQARFPQVSLAREALYGHSYG GLLALHALFTRPQSFDCYIASSPSIWWNSLCILHEAKAFVETKKVSHDQS PSLMVSWGSWEQHPPRWADELLDHYEARKRTAAELRMADNALDLCAMLHG CSRLHALIKTEYEGEDHTSVMSCSVSRGLTMFFEDWPFHQSG
References
Title: Iron Scavenging in Aspergillus Species: Structural and Biochemical Insights into Fungal Siderophore Esterases Ecker F, Haas H, Groll M, Huber EM Ref: Angew Chem Int Ed Engl, 57:14624, 2018 : PubMed
Fungi utilize high-affinity chelators termed siderophores with chemically diverse structures to scavenge the essential nutrient iron from their surroundings. Since they are among the strongest known Fe(3+) binding agents, intracellular release of the heavy metal atom is facilitated by the activity of specific hydrolases. In this work, we report the characterization and X-ray crystal structures of four siderophore esterases: AfEstB and AfSidJ from Aspergillus fumigatus, as well as AnEstB and AnEstA from Aspergillus nidulans. Even though they all display the conserved alpha/beta-hydrolase fold, we found significant structural and enzymatic discrepancies in their adaption to both related and chemically diverse substrates. A structure of AfEstB in complex with its substrate triacetylfusarinine C gives insight into the active enzyme and shows tetrahedral coordination between the catalytic serine and the scissile ester bond.
We present the genome sequences of a new clinical isolate of the important human pathogen, Aspergillus fumigatus, A1163, and two closely related but rarely pathogenic species, Neosartorya fischeri NRRL181 and Aspergillus clavatus NRRL1. Comparative genomic analysis of A1163 with the recently sequenced A. fumigatus isolate Af293 has identified core, variable and up to 2% unique genes in each genome. While the core genes are 99.8% identical at the nucleotide level, identity for variable genes can be as low 40%. The most divergent loci appear to contain heterokaryon incompatibility (het) genes associated with fungal programmed cell death such as developmental regulator rosA. Cross-species comparison has revealed that 8.5%, 13.5% and 12.6%, respectively, of A. fumigatus, N. fischeri and A. clavatus genes are species-specific. These genes are significantly smaller in size than core genes, contain fewer exons and exhibit a subtelomeric bias. Most of them cluster together in 13 chromosomal islands, which are enriched for pseudogenes, transposons and other repetitive elements. At least 20% of A. fumigatus-specific genes appear to be functional and involved in carbohydrate and chitin catabolism, transport, detoxification, secondary metabolism and other functions that may facilitate the adaptation to heterogeneous environments such as soil or a mammalian host. Contrary to what was suggested previously, their origin cannot be attributed to horizontal gene transfer (HGT), but instead is likely to involve duplication, diversification and differential gene loss (DDL). The role of duplication in the origin of lineage-specific genes is further underlined by the discovery of genomic islands that seem to function as designated "gene dumps" and, perhaps, simultaneously, as "gene factories".
Title: EstB-mediated hydrolysis of the siderophore triacetylfusarinine C optimizes iron uptake of Aspergillus fumigatus Kragl C, Schrettl M, Abt B, Sarg B, Lindner HH, Haas H Ref: Eukaryot Cell, 6:1278, 2007 : PubMed
Aspergillus fumigatus excretes the fusarinine-type siderophore desferri-triacetylfusarinine C (DF-TafC) to mobilize iron. DF-TafC is a cyclic peptide consisting of three N(5)-cis-anhydromevalonyl-N(5)-hydroxy-N(2)-acetyl-l-ornithine residues linked by ester bonds; these linkages are in contrast to peptide linkages found for ferrichrome-type siderophores. Subsequent to the binding of iron and uptake, triacetylfusarinine C (TafC) is hydrolyzed, the cleavage products are excreted, and the iron is transferred to the metabolism or to the intracellular siderophore desferri-ferricrocin (DF-FC) for iron storage. Here we report the identification and characterization of the TafC esterase EstB, the first eukaryotic siderophore-degrading enzyme to be characterized at the molecular level. The encoding gene, estB, was found to be located in an iron-regulated gene cluster, indicating a role in iron metabolism. Deletion of estB in A. fumigatus eliminated TafC esterase activity of cellular extracts and caused increased intracellular accumulation of TafC and TafC hydrolysis products in vivo. Escherichia coli-expressed EstB displayed specific TafC esterase activity but did not hydrolyze fusarinine C, which has the same core structure as TafC but lacks three N(2)-acetyl residues. Localization of EstB via enhanced green fluorescent protein tagging suggested that TafC hydrolysis takes place in the cytoplasm. EstB abrogation reduced the intracellular transfer rate of iron from TafC to DF-FC and delayed iron sensing. Furthermore, EstB deficiency caused a decreased radial growth rate under iron-depleted but not iron-replete conditions. Taken together, these data suggest that EstB-mediated TafC hydrolysis optimizes but is not essential for TafC-mediated iron uptake in A. fumigatus.
Aspergillus fumigatus Af293 and Neosartorya fumigata (strain CEA10 / CBS 144.89 / FGSC A1163) (Aspergillus fumigatus) Siderophore esterase IroE-like AfEstB
