Phytol biosynthesis

Keeling PJ, Burger G, Dumford DG, Lang BF, Lee RW, Pearlman RE, Roger AJ, Gray MW (2005) The tree of eukaryotes. Trends Ecol Evol 20 670-676 Kim D, Filtz MR, Proteau PJ (2004) The methylerythritol phosphate pathway contributes to carotenoid but not phytol biosynthesis in Euglena gracilis. J Nat Prod 67 1067-1069... 

Kim D, Eiltz MR, Protean PJ. The methylerythritol phosphate pathway contributes to carotenoid but not phytol biosynthesis in Euglena gracilis. J. Nat. Prod. 2004 67 1067-1069. 

Since carotenoids are derived for the central isoprenoid pathway (Fig. 13.3), the regulation of their formation must involve a co-ordinated flux of isoprenoid imits into this branch of the pathway as well as into others such as the biosynthesis of sterols, gibberellins, phytol and terpenoid quinones. An imderstanding of the complexities of regulation of the pathway is necessary in order to target the regulatory steps for genetic manipulation. 

Saito, K. and Yamazaki, M., Biochemistry and molecular biology of the late-stage of biosynthesis of anthocyanin lessons from Perilla frutescens as a model plant. New Phytol, 155, 9, 2002. 

In addition to its role as an intermediate in cholesterol biosynthesis, isopentenyl pyrophosphate is the activated precursor of a huge array of biomolecules with diverse biological roles (Fig. 21-48). They include vitamins A, E, and K plant pigments such as carotene and the phytol chain of chlorophyll natural rubber many essential oils (such as the fragrant principles of lemon oil, eucalyptus, and musk) insect juvenile hormone, which controls metamorphosis dolichols, which serve as lipid-soluble carriers in complex polysaccharide synthesis and ubiquinone and plastoquinone, electron carriers in mitochondria and chloroplasts. Collectively, these molecules are called isoprenoids. More than... 

The concentration of dolichyl phosphate in eukaryotic tissues is very low and is probably rate-limiting for the glycosylation processes. Variation of the concentration in the endoplasmic-reticulum membranes is a possible way of controlling the rate of glycosylation. It is important to point out that the early steps in the dolichol biosynthesis are common to such other prenyl derivatives in plants as steroids, essential oils, hormones, phytol, and carotenes (see Scheme 1), and parameters affecting those reactions that may control the dolichol to dolichyl phosphate step could be another mechanism for regulation of the level of dolichyl phosphate. 

Itaya, N.M., Buckeridge, M.S., and Figueiredo-Ribeiro, R.C.L., Biosynthesis in vitro of high-molecular-mass fructan by cell-free extracts from tuberous roots of Viguiera discolor (Asteraceae), New Phytol., 136, 53-60, 1997. 

The carotenoids are biosynthesized by a specialized branch of the isoprenoid pathway which is used by plants for the biosynthesis of a wide variety of important compounds, including the C20 sidechain (phytol) of chlorophyll. The main stages of carotenoid biosynthesis are outlined in Fig. 1. 

Weng JK, Chappie C. (2010). The origin and evolution of lignin biosynthesis. New Phytol, 187, 273-285. 

Liljenberg (1977a) has reviewed the phytylation step in chlorophyll biosynthesis and has presented evidence for the presence of phytyl pyrophosphate and acyl esters of phytol in irradiated barley seedlings (Liljenberg, 1977b). 

Chlorophyllase (EC 3.1.1.4) a plant carboxyester-ase which catalyses the reversible transformation of chlorophyllides to chlorophyll in the last step of chlorophyll biosynthesis (Chlorophyllide a + phytol chlorophyll + H2O). The pH optimum for the reaction is 6.2. The enzyme is found in all plants, in both the green and nongreen parts such as roots. It is localized in the lipoprotein layer of the thylakoid membrane, which contains all the enzymes and pigments of the photosynthetic apparatus. 

Biosynthesis. The starting compound is geranyl pyrophosphate (see Terpenes). Acyclic D. are formed by hydrolysis of the pyrophosphate residne (e.g. phytol). Geranylgeranylpyrophosphate is probably converted easily to geranyl linalool, which is then converted to bi- and tricyclic compoimds (Rg.). In a few of the cyclic D-, e. g. abietic acid, there is a migration of the substituents. The gibberellins are derived from the labda-diene type of D. 

Lopez-Raez JA, Chamikhova T, Gomez-Roldan V, Matusova R, Kohlen W, De Vos R, Verstappen F, Puech-Pages V, Becard G, Mulder P, Bouwmeester H (2008) Tomato strigolactones are derived from carotenoids and their biosynthesis is promoted by phosphate starvation. New Phytol 178 863-874. doi 10.1111/j.l469-8137.2008.02406.x... 

L6pez-Raez JA, Kohlen W, Chamikhova T, Mulder P, Undas AK, Segeant MJ, Verstappen F, Bugg TDH, Tompson AJ, Tuyter-Spira C, Bouwmeester H (2010) Does abscisic acid affect strigolactone biosynthesis New Phytol 187 343-354. doi 10.1111/j.l469-8137.2010.03291.x... 

A Novel Mevalonate-Independent Pathway for the Biosynthesis of Carotenoids, Phytol and Prenyl Chain of Plastoquinone-9 in Green Algae and Higher Plants. 

Reddy A.R. and Das V.S.R., 1987. CTiToroplast autonomy for the biosynthesis of isopentenyldiphosphate in guayule (Parthenium argentatum Gray) New Phytol. 106, 457-464. 

Valentin, H. E., Lincoln, K., Moshiri, F., Jensen, P. K., Qi, Q., Venkatesh, T. V, Karunanandaa, B., Baszis, S. R., Norris, S. R., Savidge, B., Gmys, K. J. Last, R. L. (2006). The Arabidopsis vitamin E pathway gene5-l mutant reveals a critical role for phytol kinase in seed tocopherol biosynthesis. Plant Cell, 18, 212-224. 

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