[237] Synthesis of vitamins K

Mayer, H.; Isler, O.

doi:10.1016/s0076-6879(71)18039-1

Cited by 17 publications

(5 citation statements)

References 45 publications

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“…For chloroplast experiments, prenylated and non-prenylated naphthoquinols were formed by reduction from the corresponding quinones just prior to use: some crystals of NaBH4 were added to a mixture containing 50 p1 of the 1 mM quinone, 2.5 ml methanol, 2.5 ml diethyl ether and 0.5 ml water. After 1 min the quinol was extracted with 10 ml diethyl ether, washed three times with 5 ml water each and quantified photometrically (approximated E243nm 27 500 mol-' 1 ern-', see [9,103). The required amount was evaporated under nitrogen in the incubation vessel of the chloroplast experiments.…”

Section: Radiochenzira1s and Chemical Synthesismentioning

confidence: 99%

“…The yield of the diphosphate was 30 pCi. 1,4-Dihydroxy-Znaphthoic acid was prepared from 1 -hydroxy-2-naphthoic acid according to [2], 1,CNaphthoquinones and 2-methyl-3,4-naphthoquinones with phytyl, geranylgeranyl, farnesyl and geranyl side chain, respectively, (2-prenyl-l,4-naphthoquinones and 2-methyl-3-prenyl-1 ,Cnaphthoquinones) were synthesized as described under 'synthesis of menaquinones, general procedure' in [9] aqueous solution of sodium dithionite and was alkalinized by NAOH. After oxidizing the quinol by AgzO in the dark in dry diethylether, the product was chromatographed on a column of silicagel (1.5 x 40 cm) with light petroleum/diethylether (20-10: 1) as solvent.…”

Section: S-[methyl-'4c]mentioning

confidence: 99%

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Site of Prenylation Reaction in Synthesis of Phylloquinone (Vitamin K₁) by Spinach Chloroplasts

Schultz

Soll

Ellerbrock

1981

European Journal of Biochemistry

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In spinach chloroplasts, 1,4-dihydroxy-2-naphthoate is prenylated by phytyldiphosphate and subsequently methylated by S-adenosylmethionine to form phylloquinol. The site of the prenylation reaction is the chloroplast envelope membrane. [ [I] result in formation of menaquinones of different length of side chain. The principal steps of the synthesis of the naphthoquinone moiety are similar for both plants and bacteria [5 -71. In the present paper we wish to report on the prcnylation of 1,4-dihydroxy-2-naphthoate by phytyldiphosphate and subsequent methylation by S-adenosylmethionine to form phylloquinol in spinach chloroplasts. The site of the prenylation reaction is the chloroplast envelope membrane. 1,4-Dihydroxy-2-naphthoate MATERIALS AND METHODS Radiochenzira1,s and Chemical SynthesisS-[methyl-'4C]Adenosylmethionine (56 Ci/mol) was purchased from Amersham Buchler (Braunschweig, FRG), [U-14C]phytol (80 Ci/mol) from NEN (Dreieich, FRG).[U-'4C]Phytyl diphosphate was prepared according to [8] modified as follows : 0.75 mg (z 200 pCi) of the above labeled phytol dissolved in 25 p1 acetonitrile was added dropwise within 2 h by a micropipette to a 250-pl reaction vessel containing 100 p1 di(triethy1ammonium) phosphate (3.3 % in dry acetonitrile) and 10 pl trichloroacetonitrile. After leaving overnight at 0°C in the dark, phytyl phosphates were precipitated by adding 100 pl acetone plus 5 pl concentrated NH3. After 2 h at -20 "C the precipitate was washed twice with 100 $0.28 M NHJ in methanol to remove phytyl monophosphate. The yield of the diphosphate was 30 pCi. 1,4-Dihydroxy-Znaphthoic acid was prepared from 1 -hydroxy-2-naphthoic acid according to [2], 1,CNaphthoquinones and 2-methyl-3,4-naphthoquinones with phytyl, geranylgeranyl, farnesyl and geranyl side chain, respectively, (2-prenyl-l,4-naphthoquinones and 2-methyl-3-prenyl-1 ,Cnaphthoquinones) were synthesized as described under 'synthesis of menaquinones, general procedure' in [9] aqueous solution of sodium dithionite and was alkalinized by NAOH. After oxidizing the quinol by AgzO in the dark in dry diethylether, the product was chromatographed on a column of silicagel (1.5 x 40 cm) with light petroleum/diethylether (20-10: 1) as solvent. If necessary, the product was rechromatographed with the same system on thin-layer. For chloroplast experiments, prenylated and non-prenylated naphthoquinols were formed by reduction from the corresponding quinones just prior to use: some crystals of NaBH4 were added to a mixture containing 50 p1 of the 1 mM quinone, 2.5 ml methanol, 2.5 ml diethyl ether and 0.5 ml water. After 1 min the quinol was extracted with 10 ml diethyl ether, washed three times with 5 ml water each and quantified photometrically (approximated E243nm 27 500 mol-' 1 ern-', see [9,103). The required amount was evaporated under nitrogen in the incubation vessel of the chloroplast experiments. Isolation of Broken ChloroplastsBroken chloroplasts were prepared from intact chloroplasts isolated according to [ l l , 121; however, the concentration of Mg...

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Section: Radiochenzira1s and Chemical Synthesismentioning

confidence: 99%

Section: S-[methyl-'4c]mentioning

confidence: 99%

Site of Prenylation Reaction in Synthesis of Phylloquinone (Vitamin K₁) by Spinach Chloroplasts

Schultz

Soll

Ellerbrock

1981

European Journal of Biochemistry

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“…These organisms neither have quinones that have one or more of the prenyl residues of the side chain reduced nor MK with more than one methyl group. Methods for the extraction, purification, identification and analysis of the quinones have been reviewed extensively (9, 22, 27, 33, 46, 59, 83, 85, 96, 100–102, 113, 127, 128, 130, 144, 157, 160, 170). …”

Section: Introductionmentioning

confidence: 99%

Biosynthesis of Menaquinone (Vitamin K ₂ ) and Ubiquinone (Coenzyme Q)

Meganathan

Kwon

2009

EcoSal Plus

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Escherichia coli and Salmonella contain the naphthoquinones menaquinone (MK; vitamin K 2 ) and demethylmenaquinone and the benzoquinone ubiquinone (coenzyme Q; Q). Both quinones are derived from the shikimate pathway, which has been called a "metabolic tree with many branches." There are two different pathways for the biosynthesis of the naphthoquinones. The vast majority of prokaryotes, including E. coli and Salmonella , and the plants use the o -succinylbenzoate pathway, while a minority uses the futalosine pathway. The quinone nucleus of Q is derived directly from chorismate, while that of MK is derived from chorismate via isochorismate. The prenyl side chains of both quinones are from isopentenyl diphosphate formed by the 2- C -methyl-D-erythritol 4-phosphate (non-mevalonate) pathway and the methyl groups are from S -adenosylmethionine. In addition, MK biosynthesis requires 2-ketoglutarate and cofactors ATP, coenzyme A, and thiamine pyrophosphate. Despite the fact that both quinones originate from the shikimate pathway, there are important differences in their biosyntheses. The prenyl side chain in MK biosynthesis is introduced at the penultimate step, accompanied by decarboxylation, whereas in Q biosynthesis it is introduced at the second step, with retention of the carboxyl group. In MK biosynthesis, all the reactions of the pathway up to prenylation are carried out by soluble enzymes, whereas all the enzymes involved in Q biosynthesis except the first are membrane bound. In MK biosynthesis, the last step is a C -methylation; in Q biosynthesis, the last step is an O -methylation. In Q biosynthesis a second C -methylation and O -methylation take place in the middle part of the pathway. Despite the fact that Q and MK biosyntheses diverge at chorismate, the C -methylations in both pathways are carried out by the same methyltransferase.

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“…In the literature, various conditions are applied in this method. 33 To optimize the conditions, we tested a variety of solvents, temperature and reaction times. We found that elevated temperature and extended time resulted in the formation of by-products.…”

Section: Resultsmentioning

confidence: 99%

Synthesis of natural polyprenols for the production of biological prenylquinones and tocochromanols

Kruk

Szymańska

2023

RSC Adv.

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[237] Synthesis of vitamins K

Cited by 17 publications

References 45 publications

Site of Prenylation Reaction in Synthesis of Phylloquinone (Vitamin K₁) by Spinach Chloroplasts

Site of Prenylation Reaction in Synthesis of Phylloquinone (Vitamin K₁) by Spinach Chloroplasts

Biosynthesis of Menaquinone (Vitamin K ₂ ) and Ubiquinone (Coenzyme Q)

Synthesis of natural polyprenols for the production of biological prenylquinones and tocochromanols

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[237] Synthesis of vitamins K

Cited by 17 publications

References 45 publications

Site of Prenylation Reaction in Synthesis of Phylloquinone (Vitamin K1) by Spinach Chloroplasts

Site of Prenylation Reaction in Synthesis of Phylloquinone (Vitamin K1) by Spinach Chloroplasts

Biosynthesis of Menaquinone (Vitamin K 2 ) and Ubiquinone (Coenzyme Q)

Synthesis of natural polyprenols for the production of biological prenylquinones and tocochromanols

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Site of Prenylation Reaction in Synthesis of Phylloquinone (Vitamin K₁) by Spinach Chloroplasts

Site of Prenylation Reaction in Synthesis of Phylloquinone (Vitamin K₁) by Spinach Chloroplasts

Biosynthesis of Menaquinone (Vitamin K ₂ ) and Ubiquinone (Coenzyme Q)