Fungal products. Part XIV. Metabolic pathways from ent-kaurenoic acid to the fungal gibberellins in mutant B1-41a of Gibberella fujikuroi

Bearder, John R.; MacMillan, Jake; Phinney, Bernard O.

doi:10.1039/p19750000721

Cited by 48 publications

(36 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Thus, the major pathway to GA 14 is presumably via GA 14 -aldehyde (23), which was not detected as an intermediate in the present study. In our experiments, the wild-type strain converted GA 12 to nonpolar products, consistent with the results of Bearder et al (28), who found that GA 12 is metabolized mainly to the non-3␤-hydroxylated GA, GA 9 . The small amount of GA 3 formed from GA 12 may be the result of the low rate of 3␤-hydroxylation.…”

Section: Discussionsupporting

confidence: 81%

The P450–1 gene of Gibberella fujikuroi encodes a multifunctional enzyme in gibberellin biosynthesis

Rojas

Hedden

Gaskin

et al. 2001

Proc. Natl. Acad. Sci. U.S.A.

125

106

View full text Add to dashboard Cite

Recent studies have shown that the genes of the gibberellin (GA) biosynthesis pathway in the fungus Gibberella fujikuroi are organized in a cluster of at least seven genes. P450 -1 is one of four cytochrome P450 monooxygenase genes in this cluster. Disruption of the P450 -1 gene in the GA-producing wild-type strain IMI 58289 led to total loss of GA production. Analysis of the P450 -1-disrupted mutants indicated that GA biosynthesis was blocked immediately after ent-kaurenoic acid. The function of the P450 -1 gene product was investigated further by inserting the gene into mutants of G. fujikuroi that lack the entire GA gene cluster; the gene was highly expressed under GA production conditions in the absence of the other GA-biosynthesis genes. Cultures of transformants containing P450 -1 converted ent- cytochrome P450 ͉ ent-kaurenoid metabolism ͉ GA14 synthase

show abstract

Section: Discussionsupporting

confidence: 81%

The P450–1 gene of Gibberella fujikuroi encodes a multifunctional enzyme in gibberellin biosynthesis

Rojas

Hedden

Gaskin

et al. 2001

Proc. Natl. Acad. Sci. U.S.A.

125

106

View full text Add to dashboard Cite

show abstract

“…GA3 was the most prevalent GA produced by these fungal cultures, typically 62% ofthe total. This is in accord with earlier reports (3,11) on GA metabolism in G. fujikuroi. In well-aerated cultures the only other GA to accumulate in detectable amounts was GAI3 (38% of total).…”

Section: Discussionsupporting

confidence: 82%

“…In G. fujikuroi, the immediate precursors to GA3 are GA4 and GA7 (3,29). These GAs were found to accumulate in G. fujikuroi cultures only when cultures were grown in high (100 mL) volumes of media and at slow (160 rpm) shaker speeds, conditions that resulted in low (1.43 ppm) oxygen concentrations (Table I).…”

Section: Discussionmentioning

confidence: 99%

Light-Stimulated Gibberellin Biosynthesis in Gibberella fujikuroi

Sm¹,

Coolbaugh²

1990

Plant Physiol.

View full text Add to dashboard Cite

Gibberellins (GAs) are a group of plant growth hormones that were first isolated from the fungus Gibbere/la fujikuroi. The biosynthesis of GA in liquid cultures of the fungus has been examined using high-performance liquid chromatography and combined gas chromatography-mass spectrometry. GA3 was the predominant GA in well-aerated cultures. GA4 and GA7, intermediates in GA3 biosynthesis, accumulated in cultures with low levels of dissolved oxygen, but were not detectable in more highly aerated cultures. Light stimulated the production of GA3 in G. fujikuroi cultures grown from young stock cultures. Cell-free enzyme studies revealed a significant stimulation in the levels of kaurenoic acid oxidation in cultures grown in the light in comparison with those grown in the dark. However, measurements of the relative rates of [14CJmevalonic acid incorporation into kaurene showed no effect of light on this early part of the pathway. Preliminary experiments indicated that blue light is most effective in enhancing kaurenoic acid oxidation.GAs4 were first isolated from the Ascomycete Gibberella fujikuroi (Sawanda) Wollenweber (Fusarium moniliforme Sheld, imperfect stage). They have since been found to occur widely in higher plants. GAs have also been found in the lower vascular plants Psilotum nudum (28) and Lygodium japonicum (31); in two other Ascomycetes; Sphaceloma manihoticola (25) and Neurospora crassa (17); and in the bacteria Rhizobium phaseoli (1) and Azospirillum lipoferum (4).GAs are synthesized from MVA via the isoprenoid pathway. Four molecules of MVA are incorporated into entkaurene, a tetracyclic compound (9) that is converted through a series of oxidative reactions to GA12-aldehyde (2). GA12-aldehyde is a branch point from which either 3-,B-hydroxylated or non-3-#-hydroxylated GAs may be formed (13).There have been reports of light acting as a regulator of GA biosynthesis in G. fujikuroi. Zweig and DeVay (32) found that "cultures which were kept in darkness usually produced less GA than cultures which were kept in the light." Mertz and '

show abstract

“…A GA-deficient mutant of G. fujikuroi, B1-41a, which lacks ent-kaurenoic acid oxidation, was used to elucidate the GA biosynthetic pathway. 3) Phaeosphaeria sp. L487 can also be considered a model fungus for GA biosynthetic studies.…”

Section: Reviewmentioning

confidence: 99%