Di Lorenzo Flaviana, Palmigiano Angelo, Al Bitar-Nehme Sami, Sturiale Luisa, Duda Katarzyna A, Gully Djamel, Lanzetta Rosa, Giraud Eric, Garozzo Domenico, Bernardini Maria Lina, Molinaro Antonio, Silipo Alba
Department of Chemical Sciences, University of Naples, Federico II, via Cinthia 4, 80126, Naples, Italy.
CNR-Istituto per i Polimeri, Compositi e Biomateriali IPCB-Unità di Catania, Via Gaifami 18, 95126, Catania, Italy.
Chemistry. 2017 Mar 13;23(15):3637-3647. doi: 10.1002/chem.201604379. Epub 2016 Dec 22.
The search for novel lipid A analogues from any biological source that can act as antagonists, displaying inhibitory activity towards the production of pro-inflammatory cytokines, or as immunomodulators in mammals, is a very topical issue. To this aim, the structure and immunological properties of the lipopolysaccharide lipid A from the purple nonsulfur bacterium Rhodopseudomonas palustris strain BisA53 have been determined. This lipid A displays a unique structural feature, with a non-phosphorylated skeleton made up of the tetrasaccharide Manp-α-(1→4)-GlcpN3N-β-1→6-GlcpN3N-α-(1→1)-α-GalpA, and four primary amide-linked 14:0(3-OH) and, as secondary O-acyl substituents, a 16:0 and the very long-chain fatty acid 26:0(25-OAc), appended on the GlcpN3N units. This lipid A architecture is definitely rare, so far identified only in the genus Bradyrhizobium. Immunological tests on both murine bone-marrow-derived and human monocyte-derived macrophages revealed an extremely low immunostimulant capability of this LPS lipid A.
从任何生物来源寻找新型脂质A类似物，使其能够作为拮抗剂，对促炎细胞因子的产生表现出抑制活性，或在哺乳动物中作为免疫调节剂，这是一个非常热门的问题。为此，已确定了来自紫色非硫细菌沼泽红假单胞菌菌株BisA53的脂多糖脂质A的结构和免疫特性。这种脂质A具有独特的结构特征，其非磷酸化骨架由四糖Manp-α-(1→4)-GlcpN3N-β-1→6-GlcpN3N-α-(1→1)-α-GalpA组成，还有四个一级酰胺连接的14:0(3-OH)，以及作为二级O-酰基取代基的一个16:0和非常长链脂肪酸26:0(25-OAc)，连接在GlcpN3N单元上。这种脂质A结构绝对罕见，迄今为止仅在慢生根瘤菌属中鉴定到。对小鼠骨髓来源和人单核细胞来源的巨噬细胞进行的免疫测试表明，这种LPS脂质A的免疫刺激能力极低。
