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PubMed · 3970697

An intermediate in cyclic beta 1-2 glucan biosynthesis.

A Zorreguieta·R A Ugalde·L F Leloir
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Abstract

Incubation of UDP-[14C]Glc with the inner membranes of Agrobacterium tumefaciens leads to the formation of cyclic beta 1-2 glucan and trichloroacetic acid-insoluble compounds. The proteolysis products of the latter show a positive charge in acid and a negative charge in alkaline buffers. The cyclic beta 1-2 glucan and the trichloroacetic acid insoluble compounds yield the same products on partial acid hydrolysis. Addition of excess non-radioactive UDP-Glc to the reaction mixture nearly stops the formation of radioactive beta 1-2 glucan and leads to a rapid fall of radioactivity in the trichloroacetic acid precipitate. Alkaline treatment of the insoluble compounds under conditions of beta-elimination leads to the partial release of free saccharides (about 30%). It is concluded that beta 1-2 glucan chains are built up joined to a protein and then released as free cyclic beta 1-2 glucan.

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Chromatography, PaperElectrophoresis, Polyacrylamide GelGlucansHydrogen-Ion ConcentrationModels, ChemicalRhizobiumbeta-GlucansJournal Article

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A Zorreguieta, R A Ugalde, L F Leloir. 1985-01-16. An intermediate in cyclic beta 1-2 glucan biosynthesis.. https://doi.org/10.1016/0006-291x(85)90613-8

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