Title: | Cyclofarnesoids and methylhexanoids produced from beta-carotene in Phycomyces blakesleeanus |
Author(s): | Alcalde E; Medina HR; Herrador MM; Barrero AF; Cerda-Olmedo E; |
Address: | "Departamento de Genetica, Universidad de Sevilla, Apartado 1095, E-41080 Sevilla, Spain. Electronic address: eugenalc@gmail.com. Departamento de Genetica, Universidad de Sevilla, Apartado 1095, E-41080 Sevilla, Spain. Electronic address: hurmedina@gmail.com. Departamento de Quimica Organica, Instituto de Biotecnologia, Universidad de Granada, Fuente Nueva s/n, E-18071 Granada, Spain. Electronic address: mmar@ugr.es. Departamento de Quimica Organica, Instituto de Biotecnologia, Universidad de Granada, Fuente Nueva s/n, E-18071 Granada, Spain. Electronic address: afbarre@ugr.es. Departamento de Genetica, Universidad de Sevilla, Apartado 1095, E-41080 Sevilla, Spain. Electronic address: eco@us.es" |
DOI: | 10.1016/j.phytochem.2016.01.013 |
ISSN/ISBN: | 1873-3700 (Electronic) 0031-9422 (Linking) |
Abstract: | "The oxidative cleavage of beta-carotene in the Mucorales produces three fragments of 18, 15, and 7 carbons, respective heads of three families of apocarotenoids: the methylhexanoids, the trisporoids, and the cyclofarnesoids (named after their 1,6-cyclofarnesane skeleton). The apocarotenoids are easily recognized because they are absent in white mutants unable to produce beta-carotene. In cultures of Phycomyces blakesleeanus we detected thirty-two apocarotenoids by LC, UV absorbance, and MS. With additional IR and NMR we identified two methylhexanoids and the eight most abundant cyclofarnesoids. Four of them were previously-unknown natural compounds, including 4-dihydrocyclofarnesine S, the most abundant cyclofarnesoid in young cultures. We arranged the apocarotenoids of the Mucorales in a scheme that helps classifying and naming them and suggests possible metabolites and biosynthetic pathways. We propose specific biosynthetic pathways for cyclofarnesoids and methylhexanoids based on structural comparisons, the time course of appearance of individual compounds, and the bioconversion of beta-apo-12-carotenol, an early precursor, to three more oxygenated cyclofarnesoids by the white mutants. Some of the reactions occur spontaneously in the increasingly acidic culture media. Mating increased the contents of methylhexanoids and cyclofarnesoids by ca. threefold in young cultures and ca. twelvefold in old ones (five days); cyclofarnesine S, the most abundant cyclofarnesoid in old cultures, increased over one hundredfold. We found no differences between the sexes and no activity as sexual pheromones, but we suggest that methylhexanoids and cyclofarnesoids could mediate species-specific physiology and behavior" |
Keywords: | "Biosynthetic Pathways Carotenoids/*chemistry/*metabolism Culture Media/chemistry Mucorales/*metabolism Nuclear Magnetic Resonance, Biomolecular Phycomyces/*chemistry Sex Attractants/metabolism beta Carotene/*chemistry Apocarotenoids Bioconversion Cyclofar;" |
Notes: | "MedlineAlcalde, Eugenio Medina, Humberto R Herrador, M Mar Barrero, Alejandro F Cerda-Olmedo, Enrique eng Research Support, Non-U.S. Gov't England 2016/02/09 Phytochemistry. 2016 Apr; 124:38-45. doi: 10.1016/j.phytochem.2016.01.013. Epub 2016 Feb 4" |