The bioconversion of 5-deoxystrigol to sorgomol by the sorghum, Sorghum bicolor (L.) Moench

Motonami, Noriko; Ueno, Kotomi; Nakashima, Hitomi; Nomura, Saki; Mizutani, Masaharu; Takikawa, Hirosato; Sugimoto, Yukihiro

doi:10.1016/j.phytochem.2013.02.017

Cited by 30 publications

(26 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For example, the cytochrome P-450 enzymes are involved in the detoxification of xenobiotics such as herbicides, and are implicated in herbicide resistance in a number of plant species. 22,23 As reported previously, 18 sorghum converted 5-deoxystrigol (8) to sorgomol 7probably by a P-450 enzyme because uniconazole-P inhibited the conversion whereas prohexadione, a 2oxoglutarate-dependent dioxygenase inhibitor, had no inhibitory effect on the conversion. Involvement of a P-450 enzyme in hydroxylation of GR24 is uncertain due to ambiguous effect of uniconazole-P on the conversion.…”

Section: Identification Of the Hydroxylated Products Of Gr24supporting

confidence: 72%

Regioselective and stereospecific hydroxylation of GR24 by Sorghum bicolor and evaluation of germination inducing activities of hydroxylated GR24 stereoisomers toward seeds of Striga species

Ueno

Ishiwa

Nakashima

et al. 2015

Bioorganic & Medicinal Chemistry

Self Cite

View full text Add to dashboard Cite

Bioconversion of GR24, the most widely used synthetic strigolactone (SL), by hydroponically grown sorghum (Sorghum bicolor) and biological activities of hydroxylated GR24 stereoisomers were studied. Analysis of extracts and exudates of sorghum roots previously fed with a racemic and diastereomeric mixture of GR24, using liquid chromatography-tandem mass spectrometry with multiple reaction monitoring (MRM), confirmed uptake of GR24 and suggested its conversion to mono-hydroxylated products. Two major GR24 metabolites, 7-hydroxy-GR24 and 8-hydroxy-GR24, were identified in the root extracts and exudates by direct comparison of chromatographic behavior with a series of synthetic mono-hydroxylated GR24 analogues. Separate feeding experiments with each of the GR24 stereoisomers revealed that the hydroxylated products were derived from 2'-epi-GR24, an evidence of sterical recognition of the GR24 molecule by sorghum. Trans-4-hydroxy-GR24 isomers derived from all GR24 stereoisomers were detected in the exudates as minor metabolites. The synthetic hydroxy-GR24 isomers induced germination of Striga hermonthica in decreasing order of C-8>C-7>C-6>C-5>C-4. In contrast the stereoisomers having the same configuration of orobanchol, irrespective of position of hydroxylation, induced germination of Striga gesnerioides. The results confirm previous reports on structural requirements of SLs and ascribe a critical role to hydroxylation, but not to the position of the hydroxyl group in the AB part of the molecule, in induction of S. gesnerioides seed germination.

show abstract

Section: Identification Of the Hydroxylated Products Of Gr24supporting

confidence: 72%

Regioselective and stereospecific hydroxylation of GR24 by Sorghum bicolor and evaluation of germination inducing activities of hydroxylated GR24 stereoisomers toward seeds of Striga species

Ueno

Ishiwa

Nakashima

et al. 2015

Bioorganic & Medicinal Chemistry

Self Cite

View full text Add to dashboard Cite

show abstract

“…We propose that e nt -2'- epi- 5-deoxystrigol ( 2 ) is the precursor for the remaining rice SLs. Further supporting this hypothesis, it has been recently shown that a sorghum enzyme(s) - likely a cytochrome P450 - converts e nt -2'- epi- 5-deoxystrigol ( 1 ) and 5-deoxystrigol ( 8a , R 1 = CH 3 ; R 2 = H) into e nt -2'- epi -sorgomol and sorgomol respectively [35]. Breeding for a different SL composition would be greatly aided by the characterization of these later steps in SL biosynthesis, that is the decoration of the SLs' core-structure.…”

Section: Discussionmentioning

confidence: 89%

Differential Activity of Striga hermonthica Seed Germination Stimulants and Gigaspora rosea Hyphal Branching Factors in Rice and Their Contribution to Underground Communication

et al. 2014

View full text Add to dashboard Cite

Strigolactones (SLs) trigger germination of parasitic plant seeds and hyphal branching of symbiotic arbuscular mycorrhizal (AM) fungi. There is extensive structural variation in SLs and plants usually produce blends of different SLs. The structural variation among natural SLs has been shown to impact their biological activity as hyphal branching and parasitic plant seed germination stimulants. In this study, rice root exudates were fractioned by HPLC. The resulting fractions were analyzed by MRM-LC-MS to investigate the presence of SLs and tested using bioassays to assess their Striga hermonthica seed germination and Gigaspora rosea hyphal branching stimulatory activities. A substantial number of active fractions were revealed often with very different effect on seed germination and hyphal branching. Fractions containing (−)−orobanchol and ent-2'-epi-5-deoxystrigol contributed little to the induction of S. hermonthica seed germination but strongly stimulated AM fungal hyphal branching. Three SLs in one fraction, putative methoxy-5-deoxystrigol isomers, had moderate seed germination and hyphal branching inducing activity. Two fractions contained strong germination stimulants but displayed only modest hyphal branching activity. We provide evidence that these stimulants are likely SLs although no SL-representative masses could be detected using MRM-LC-MS. Our results show that seed germination and hyphal branching are induced to very different extents by the various SLs (or other stimulants) present in rice root exudates. We propose that the development of rice varieties with different SL composition is a promising strategy to reduce parasitic plant infestation while maintaining symbiosis with AM fungi.

show abstract

“…It is not known whether decoration generally occurs before, after or concurrently with the formation of the ABC-ring. In Sorghum there is evidence that hydroxylation can occur after ABC-ring formation, because exogenously supplied 5-DS and ent-2 0 -epi-5-DS are taken up, hydroxylated at the C9 position, and exuded as sorgomol and ent-2 0 -epi-sorgomol, respectively (Motonami et al, 2013). A better understanding of where, when and how these different SLs are synthesized will be important in understanding their distinct roles.…”

Section: Sl Diversitymentioning

confidence: 99%

Strigolactones and the control of plant development: lessons from shoot branching

2014

View full text Add to dashboard Cite

SUMMARYStrigolactones (SLs) were originally identified through their activities as root exudates in the rhizosphere; however, it is now clear that they have many endogenous signalling roles in plants. In this review we discuss recent progress in understanding SL action in planta, particularly in the context of the regulation of shoot branching, one of the best-characterized endogenous roles for SLs. Rapid progress has been made in understanding SL biosynthesis, but many questions remain unanswered. There are hints of as yet unidentified sources of SL, as well as unknown SL-like molecules with important signalling functions. SL signalling is even more enigmatic. Although a likely receptor has been identified, along with some candidate immediate downstream targets, our understanding of how these targets mediate SL signalling is limited. There is still considerable uncertainty about whether the targets of SL signalling are primarily transcriptional or not. There is at least one non-transcriptional target, because a rapid primary response to SL is the removal of PIN1 auxin exporter proteins from the plasma membrane in vascular-associated cells of the stem. We discuss how the various early events in SL signalling could result in the observed changes in shoot branching.

show abstract

The bioconversion of 5-deoxystrigol to sorgomol by the sorghum, Sorghum bicolor (L.) Moench

Cited by 30 publications

References 20 publications

Regioselective and stereospecific hydroxylation of GR24 by Sorghum bicolor and evaluation of germination inducing activities of hydroxylated GR24 stereoisomers toward seeds of Striga species

Regioselective and stereospecific hydroxylation of GR24 by Sorghum bicolor and evaluation of germination inducing activities of hydroxylated GR24 stereoisomers toward seeds of Striga species

Differential Activity of Striga hermonthica Seed Germination Stimulants and Gigaspora rosea Hyphal Branching Factors in Rice and Their Contribution to Underground Communication

Strigolactones and the control of plant development: lessons from shoot branching

Contact Info

Product

Resources

About