21176790

not annotated - annotated - LINNAEUS only

Characterization of a polyketide synthase in Aspergillus niger whose product is a precursor for both dihydroxynaphthalene (DHN) melanin and naphtho-gamma-pyrone.

The genome sequencing of the fungus Aspergillus niger uncovered a large cache of genes encoding enzymes thought to be involved in the production of secondary metabolites yet to be identified. Identification and structural characterization of many of these predicted secondary metabolites are hampered by their low concentration relative to the known A. niger metabolites such as the naphtho-gamma-pyrone family of polyketides. We deleted a non-reducing PKS gene in A. niger strain ATCC 11414, a daughter strain of A. niger ATCC strain 1015 whose genome was sequenced by the DOE Joint Genome Institute. This PKS encoding gene we name albA is a predicted ortholog of alb1 from Aspergillus fumigatus which is responsible for production of the naphtho-gamma-pyrone precursor for the 1,8-dihydroxynaphthalene (DHN) melanin/spore pigment. Our results show that the A. nigeralbA PKS is responsible for both the production of the spore pigment precursor and a family of naphtho-gamma-pyrones commonly found in significant quantity in A. niger culture extracts. The generation of an A. niger strain devoid of naphtho-gamma-pyrones will greatly facilitate the elucidation of cryptic biosynthetic pathways in this organism.



Ann file

T1	Species 45 62	Aspergillus niger

N1 Reference T1 Taxonomy:5061

T2 Species 200 217 Aspergillus niger

N2 Reference T2 Taxonomy:5061

T3 Species 514 522 A. niger

N3 Reference T3 Taxonomy:5061

T4 Species 629 655 A. niger strain ATCC 11414

N4 Reference T4 Taxonomy:5061

T5 Species 678 703 A. niger ATCC strain 1015

N5 Reference T5 Taxonomy:5061

T6 Species 839 860 Aspergillus fumigatus

N6 Reference T6 Taxonomy:746128

T7 Species 1023 1035 A. nigeralbA

N7 Reference T7 Taxonomy:5061

T8 Species 1190 1198 A. niger

N8 Reference T8 Taxonomy:5061

T9 Species 1238 1246 A. niger

N9 Reference T9 Taxonomy:5061