Evidence for glycogenin autoglucosylation cessation by inaccessibility of the acquired maltosaccharide

JORGE M. ROMERO, FEDERICO M. ISSOGLIO, MARÍA E. CARRIZO AND JUAN A. CURTINO

Elsevier

Año: 2008 vol. 374 p. 704 - 704

p class="MsoBodyText" style="MARGIN: 0cm 0cm 0pt; tab-stops: 0cm 144.0pt 180.0pt 216.0pt 252.0pt 288.0pt 324.0pt 360.0pt 396.0pt 432.0pt 468.0pt 504.0pt 540.0pt 576.0pt 612.0pt 648.0pt 684.0pt 720.0pt 756.0pt 792.0pt 828.0pt 864.0pt 900.0pt 936.0pt 972.0pt 1008.0pt 1044.0pt 1080.0pt 1116.0pt 1152.0pt 1188.0pt 1224.0pt 1260.0pt 1296.0pt 1332.0pt 1368.0pt 1404.0pt 1440.0pt 1476.0pt">Glycogenin initiates the biosynthesis of proteoglycogen, the mammalian glycogenin-bound glycogen, by intramolecular autoglucosylation. The incubation of glycogenin with UDP-glucose results in formation of a tyrosine-bound maltosaccharide, reaching maximum polymerization degree of 13 glucose units at cessation of the reaction. No exhaustion of the substrate donor occurred at the autoglucosylation end and the full autoglucosylated enzyme continued catalytically active for transglucosylation of t