RT Journal Article SR Electronic(1) A1 Baldessari, Alicia A1 Ielpi, Luis A1 Dankert, Marcelo A.YR 1990 T1 A novel galacturonide from Xanthomonas campestris JF Microbiology, VO 136 IS 8 SP 1501 OP 1507 DO https://doi.org/10.1099/00221287-136-8-1501 PB Microbiology Society, SN 1465-2080, AB Enzyme preparations from Xanthomonas campestris incubated in the presence of UDP-[14C]GlcA and Mg2+ produced a lipophilic galacturonide with unusual properties. It was easily degraded by both mild acid treatment (0·01 m-HCl, 100 °C, 10 min) and mild alkali treatment (0·06 m-NaOH, room temperature, 5 min) releasing free [14C]galacturonic acid. The galacturonide appeared to be a single compound with one negative charge, as judged by TLC, paper electrophoresis and chromatography, LH-20 gel filtration and DEAE-cellulose column chromatography. Competition experiments indicated that the true glycosyl donor was UDP-GalA, in agreement with the detection of UDP-GlcA-4-epimerase activity in the crude enzyme preparation. The transglycosidase activity was located mainly in the membrane fraction. UDP inhibited the reaction and even produced some loss of label, suggesting an easily reversible reaction. UMP had almost no effect., UL https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-136-8-1501