N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 119991 Moscow, Russia.
Centre for Immunology and Infection Control, School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Brisbane, QLD 4059, Australia.
Int J Mol Sci. 2021 May 26;22(11):5641. doi: 10.3390/ijms22115641.
Whole genome sequences of two clinical isolates, 48-1789 and MAR24, revealed that they carry the KL106 and KL112 capsular polysaccharide (CPS) biosynthesis gene clusters, respectively, at the chromosomal K locus. The KL106 and KL112 gene clusters are related to the previously described KL11 and KL83 gene clusters, sharing genes for the synthesis of l-rhamnose (l-Rha) and 6-deoxy-l-talose (l-6dTal). CPS material isolated from 48-1789 and MAR24 was studied by sugar analysis and Smith degradation along with one- and two-dimensional 1H and 13C NMR spectroscopy. The structures of K106 and K112 oligosaccharide repeats (K units) l-6dTal-(1→3)-D-GlcNAc tetrasaccharide fragment share the responsible genes in the respective gene clusters. The K106 and K83 CPSs also have the same linkage between K units. The KL112 cluster includes an additional glycosyltransferase gene, Gtr183, and the K112 unit includes α l-Rha side chain that is not found in the K106 structure. K112 further differs in the linkage between K units formed by the Wzy polymerase, and a different gene is found in KL112. However, though both KL106 and KL112 share the acetyltransferase gene with KL83, only K83 is acetylated.
两个临床分离株 48-1789 和 MAR24 的全基因组序列显示，它们分别在染色体 K 位携带 KL106 和 KL112 荚膜多糖（CPS）生物合成基因簇。KL106 和 KL112 基因簇与先前描述的 KL11 和 KL83 基因簇有关，它们共享用于合成 l-鼠李糖（l-Rha）和 6-脱氧-l-塔洛糖（l-6dTal）的基因。从 48-1789 和 MAR24 分离的 CPS 材料通过糖分析和 Smith 降解以及一维和二维 1H 和 13C NMR 光谱进行了研究。K106 和 K112 寡糖重复（K 单位）l-6dTal-（1→3）-D-GlcNAc 四糖片段的结构在各自的基因簇中共享负责基因。K106 和 K83 CPS 也具有相同的 K 单位之间的键合。KL112 簇包含额外的糖基转移酶基因 Gtr183，并且 K112 单元包含在 K106 结构中未发现的α l-Rha 侧链。K112 进一步在由 Wzy 聚合酶形成的 K 单位之间的键合中不同，并且在 KL112 中发现了不同的基因。然而，尽管 KL106 和 KL112 与 KL83 共享乙酰基转移酶基因，但只有 K83 被乙酰化。
