Open AccessIsolation and Characterization of the Gibberellin Biosynthetic Gene Cluster in Sphaceloma manihoticola
Author(s) -
Christiane Bömke,
María Cecilia Rojas,
Fan Gong,
Peter Hedden,
Bettina Tudzynski
Publication year - 2008
Publication title -
applied and environmental microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.552
H-Index - 324
eISSN - 1070-6291
pISSN - 0099-2240
DOI - 10.1128/aem.00694-08
Subject(s) - gibberella fujikuroi , gene cluster , biology , gene , genetics , polyketide synthase , intron , gibberellin , biosynthesis , polyketide
Gibberellins (GAs) are tetracyclic diterpenoid phytohormones that were first identified as secondary metabolites of the fungusFusarium fujikuroi (teleomorph,Gibberella fujikuroi ). GAs were also found in the cassava pathogenSphaceloma manihoticola , but the spectrum of GAs differed from that inF. fujikuroi . In contrast toF. fujikuroi , the GA biosynthetic pathway has not been studied in detail inS. manihoticola , and none of the GA biosynthetic genes have been cloned from the species. Here, we present the identification of the GA biosynthetic gene cluster fromS. manihoticola consisting of five genes encoding a bifunctionalent -copalyl/ent -kaurene synthase (CPS/KS), a pathway-specific geranylgeranyl diphosphate synthase (GGS2), and three cytochrome P450 monooxygenases. The functions of all of the genes were analyzed either by a gene replacement approach or by complementing the correspondingF. fujikuroi mutants. The cluster organization and gene functions are similar to those inF. fujikuroi . However, the two border genes in theFusarium cluster encoding the GA4 desaturase (DES) and the 13-hydroxylase (P450-3) are absent in theS. manihoticola GA gene cluster, consistent with the spectrum of GAs produced by this fungus. The close similarity between the two GA gene clusters, the identical gene functions, and the conserved intron positions suggest a common evolutionary origin despite the distant relatedness of the two fungi.