Mastio Roberto, Willén Daniel, Söderlund Zackarias, Westergren-Thorsson Gunilla, Manner Sophie, Tykesson Emil, Ellervik Ulf
Centre for Analysis and Synthesis, Centre for Chemistry and Chemical Engineering, Lund University P. O. Box 124 SE-221 00 Lund Sweden
Department of Experimental Medical Science, Lund University P. O. Box 117 SE-221 00 Lund Sweden.
RSC Adv. 2021 Nov 29;11(60):38283-38292. doi: 10.1039/d1ra06320k. eCollection 2021 Nov 23.
Five novel xylosides tagged with the fluorescent probe Pacific Blue™ were synthesized and found to act as substrates for β4GalT7, a bottleneck enzyme in the biosynthetic pathways leading to glycosaminoglycans. By confocal microscopy of A549 cells, we showed that the xylosides were taken up by the cells, but did not enter the Golgi apparatus where most of the glycosaminoglycan biosynthesis occurs. Instead, after a possible double galactosylation by β4GalT7 and β3GalT6, the biosynthesis was terminated. We hypothesize this is due to the charge of the fluorescent probe, which is required for fluorescent ability and stability under physiological conditions.
合成了五种标记有荧光探针Pacific Blue™的新型木糖苷，发现它们可作为β4GalT7的底物，β4GalT7是导致糖胺聚糖生物合成途径中的瓶颈酶。通过对A549细胞进行共聚焦显微镜观察，我们发现木糖苷被细胞摄取，但并未进入大多数糖胺聚糖生物合成发生的高尔基体。相反，在可能经过β4GalT7和β3GalT6的双半乳糖基化后，生物合成终止。我们推测这是由于荧光探针的电荷所致，该电荷是生理条件下荧光能力和稳定性所必需的。
