The monotopic phosphoglycosyl transferase (monoPGT) superfamily comprises over 38,000 nonredundant sequences represented in bacterial and archaeal domains of life. Members of the superfamily catalyze the first membrane-committed step in en bloc oligosaccharide biosynthetic pathways, transferring a phosphosugar from a soluble nucleoside diphosphosugar to a membrane-resident polyprenol phosphate. The singularity of the monoPGT fold and its employment in the pivotal first membrane-committed step allows confident assignment of both protein and corresponding pathway. The diversity of the family is revealed by the generation and analysis of a sequence similarity network for the superfamily, with fusion of monoPGTs with other pathway members being the most frequent and extensive elaboration. Three common fusions were identified: sugar-modifying enzymes, glycosyl transferases, and regulatory domains. Additionally, unexpected fusions of the monoPGT with members of the polytopic PGT superfamily were discovered, implying a possible evolutionary link through the shared polyprenol phosphate substrate. Notably, a phylogenetic reconstruction of the monoPGT superfamily shows a radial burst of functionalization, with a minority of members comprising only the minimal PGT catalytic domain. The commonality and identity of the fusion partners in the monoPGT superfamily is consistent with advantageous colocalization of pathway members at membrane interfaces.

单位磷酸糖基转移酶 (monoPGT) 超家族包含超过 38,000 个非冗余序列，这些序列代表于生命的细菌和古细菌领域。该超家族的成员催化整体寡糖生物合成途径中的第一个膜承诺步骤，将磷酸糖从可溶性核苷二磷酸糖转移到膜驻留的聚异戊二烯磷酸酯中。monoPGT 折叠的奇异性及其在关键的第一个膜提交步骤中的使用允许对蛋白质和相应的途径进行自信的分配。该家族的多样性通过超家族的序列相似性网络的生成和分析来揭示，monoPGTs 与其他途径成员的融合是最常见和最广泛的阐述。确定了三种常见的融合：糖修饰酶，糖基转移酶和调节结构域。此外，发现了 monoPGT 与多体 PGT 超家族成员的意外融合，这暗示了通过共享的聚异戊二烯磷酸酯底物可能存在进化联系。值得注意的是，monoPGT 超家族的系统发育重建显示出功能化的径向爆发，少数成员仅包含最小的 PGT 催化结构域。monoPGT 超家族中融合伙伴的共性和同一性与膜界面上通路成员的有利共定位一致。monoPGT 超家族的系统发育重建显示出功能化的径向爆发，少数成员仅包含最小的 PGT 催化结构域。monoPGT 超家族中融合伙伴的共性和同一性与膜界面上通路成员的有利共定位一致。monoPGT 超家族的系统发育重建显示出功能化的径向爆发，少数成员仅包含最小的 PGT 催化结构域。monoPGT 超家族中融合伙伴的共性和同一性与膜界面上通路成员的有利共定位一致。