Di Lorenzo Flaviana
Department of Chemical Sciences, University of Naples Federico II, Via Cinthia 4, 80126, Naples, Italy.
Antonie Van Leeuwenhoek. 2017 Nov;110(11):1401-1412. doi: 10.1007/s10482-017-0865-z. Epub 2017 Mar 31.
Suberites domuncula is a marine demosponge harbouring a large bacterioflora, including commensal, opportunistic and pathogenic bacteria, among which, species of the Gram-negative genus Pseudoalteromonas were identified. The sponge-bacteria interaction mechanisms are still not fully understood. As the main component of the Gram-negative bacterial outer membrane, the lipopolysaccharide (LPS) may play a role in such a crucial relationship. Moreover, the LPS is known to be the most versatile bioactive macromolecule of Gram-negative bacteria and its lipid A structure is responsible for the immunological activity of the whole LPS on eukaryotic host cells. Here it is reported the structural characterisation of the LPS lipid A moiety isolated from the S. domuncula-associated commensal bacterium, Pseudoalteromonas sp. 2A. Chemical and MALDI mass spectrometry analyses, performed on both the LPS and the isolated lipid A as well as on the intact bacterial cells, highlighted a complex family of penta-acylated lipid A species carrying two phosphate units on the disaccharide backbone.
蜂巢海绵（Suberites domuncula）是一种海洋海绵，含有大量细菌群落，包括共生菌、机会致病菌和病原菌，其中已鉴定出革兰氏阴性假交替单胞菌属（Pseudoalteromonas）的物种。海绵与细菌的相互作用机制仍未完全了解。作为革兰氏阴性细菌外膜的主要成分，脂多糖（LPS）可能在这种关键关系中发挥作用。此外，已知LPS是革兰氏阴性细菌中最具多功能性的生物活性大分子，其脂质A结构负责整个LPS对真核宿主细胞的免疫活性。本文报道了从与蜂巢海绵相关的共生细菌假交替单胞菌2A（Pseudoalteromonas sp. 2A）中分离出的LPS脂质A部分的结构表征。对LPS、分离出的脂质A以及完整细菌细胞进行的化学和基质辅助激光解吸电离质谱分析，突出显示了一个复杂的五酰化脂质A物种家族，其在二糖主链上带有两个磷酸基团。
