5-(p-aminophenyl)-1,2,3,4-tetrahydroxypentane, a structural component of the modified folate in Sulfolobus solfataricus.
The partial characterization of the modified folate present in Sulfolobus solfataricus has been carried out. Separation of ethanol-water extracts of these cells on a DEAE-Sephadex column led to the isolation of a small amount of intact oxidized cofactor, which, when subjected to reductive cleavage with Zn-HCl, produced 6-methylpterin. This indicated that the modified folate in these cells contained a nonmethylated pterin linked, via a methylene group at the C-6 position of the pterin, to an arylamine, as is found in folate. Oxidative cleavage of intact reduced cofactor produced pterin and a single arylamine. The azo dye derivative of this arylamine was prepared and purified by chromatography on a Bio-Gel P-6 column. The resulting purified compound was shown to be readily hydrolyzed in dilute acid to the azo dye derivative of 5-(p-aminophenyl)-1,2,3,4-tetrahydroxypantane, which was, in turn, readily cleaved to 5-(p-aminophenyl)-1,2,3,4- tetrahydroxypentane by Zn-HCl reduction. The stereochemistry of the resulting 5-(p-aminophenyl)-1,2,3,4-tetrahydroxypentane was shown to be ribo, the same as that of the 5-(p-aminophenyl)-1,2,3,4- tetrahydroxypentane moiety found in methanopterin. The complete arylamine side chain of the modified folate thus contains 5-(p-aminophenyl)-1,2,3,4-tetrahydroxypentane attached, via an acid-labile bond, to a currently unidentified substituent. The modified folate present in S. solfataricus thus contains structural features common to both folates and methanopterin.
Zhou
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Department of Biochemistry and Nutrition, Virginia Polytechnic Institute and State University, Blacksburg 24061-0308.
White
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RH
D005492:Folic Acid / Q000031:analogs & derivatives*; D009682:Magnetic Resonance Spectroscopy; D000439:Pentanols / Q000737:chemistry* / Q000302:isolation & purification; D011522:Protons; D011622:Pterins / Q000737:chemistry; D013237:Stereoisomerism; D016944:Sulfolobus / Q000737:chemistry*
D000439:Pentanols; D011522:Protons; D011622:Pterins; C075530:5-(p-aminophenyl)-1,2,3,4-tetrahydroxypentane; C036686:methanopterin; D005492:Folic Acid