TY - JOUR
T1 - Identification and characterization of the echinocandin b biosynthetic gene cluster from Emericella rugulosa NRRL 11440
AU - Cacho, R.A.
AU - Jiang, W.
AU - Chooi, Heng
AU - Walsh, C.T.
AU - Tang, Y.
PY - 2012
Y1 - 2012
N2 - Echinocandins are a family of fungal lipidated cyclic hexapeptide natural products. Due to their effectiveness as antifungal agents, three semisynthetic derivatives have been developed and approved for treatment of human invasive candidiasis. All six of the amino acid residues are hydroxylated, including 4R,5R-dihydroxy-l-ornithine, 4R-hydroxyl-l-proline, 3S,4S-dihydroxy-l- homotyrosine, and 3S-hydroxyl-4S-methyl-l-proline. We report here the biosynthetic gene cluster of echinocandin B 1 from Emericella rugulosa NRRL 11440 containing genes encoding for a six-module nonribosomal peptide synthetase EcdA, an acyl-AMP ligase EcdI, and oxygenases EcdG, EcdH, and EcdK. We showed EcdI activates linoleate as linoleyl-AMP and installs it on the first thiolation domain of EcdA. We have also established through ATP-PPi exchange assay that EcdA loads l-ornithine in the first module. A separate hty gene cluster encodes four enzymes for de novo generation of l-homotyrosine from acetyl-CoA and 4-hydroxyphenyl-pyruvate is found from the sequenced genome. Deletions in the ecdA, and htyA genes validate their essential roles in echinocandin B production. Five predicted iron-centered oxygenase genes, ecdG, ecdH, ecdK, htyE, and htyF, in the two separate ecd and hty clusters are likely to be the tailoring oxygenases for maturation of the nascent NRPS lipohexapeptidolactam product. © 2012 American Chemical Society.
AB - Echinocandins are a family of fungal lipidated cyclic hexapeptide natural products. Due to their effectiveness as antifungal agents, three semisynthetic derivatives have been developed and approved for treatment of human invasive candidiasis. All six of the amino acid residues are hydroxylated, including 4R,5R-dihydroxy-l-ornithine, 4R-hydroxyl-l-proline, 3S,4S-dihydroxy-l- homotyrosine, and 3S-hydroxyl-4S-methyl-l-proline. We report here the biosynthetic gene cluster of echinocandin B 1 from Emericella rugulosa NRRL 11440 containing genes encoding for a six-module nonribosomal peptide synthetase EcdA, an acyl-AMP ligase EcdI, and oxygenases EcdG, EcdH, and EcdK. We showed EcdI activates linoleate as linoleyl-AMP and installs it on the first thiolation domain of EcdA. We have also established through ATP-PPi exchange assay that EcdA loads l-ornithine in the first module. A separate hty gene cluster encodes four enzymes for de novo generation of l-homotyrosine from acetyl-CoA and 4-hydroxyphenyl-pyruvate is found from the sequenced genome. Deletions in the ecdA, and htyA genes validate their essential roles in echinocandin B production. Five predicted iron-centered oxygenase genes, ecdG, ecdH, ecdK, htyE, and htyF, in the two separate ecd and hty clusters are likely to be the tailoring oxygenases for maturation of the nascent NRPS lipohexapeptidolactam product. © 2012 American Chemical Society.
U2 - 10.1021/ja307220z
DO - 10.1021/ja307220z
M3 - Article
C2 - 22998630
VL - 134
SP - 16781
EP - 16790
JO - Journal of the Amercian Chemical Society
JF - Journal of the Amercian Chemical Society
SN - 0002-7863
IS - 40
ER -