Morohoshi Tomohiro, Xie Xiaonan, Ikeda Tsukasa
Department of Material and Environmental Chemistry, Graduate School of Engineering, Utsunomiya University, Utsunomiya, Japan.
Center for Bioscience Research and Education, Utsunomiya University, Utsunomiya, Japan.
Biosci Biotechnol Biochem. 2019 Jan;83(1):174-180. doi: 10.1080/09168451.2018.1518701. Epub 2018 Sep 10.
Numerous gram-negative bacteria have quorum-sensing systems and produce AHL as a quorum-sensing signal molecule. In this study, we demonstrated that P-1M, an isolate from a pink-pigmented household biofilm, produced two AHLs, C14:1-HSL as a predominant product and 3OHC14-HSL as a minor product. The complete genome sequence of P-1M revealed the presence of genes that are predicted to encode an AHL synthase () and AHL receptor (). P-1M formed a pellicle-like biofilm, which had a flat surface and was easily removable. In contrast, biofilms formed by and/or deletion mutants had a wavy surface structure and strongly adhered to the glass tube. When C14:1-HSL was added to the mutant culture, the biofilm structure resembled that of the wild-type strain. These results demonstrated that the structure and adhesion strength of P-1M biofilms are determined in part by AHL-mediated quorum sensing. AHL: -acyl-l-homoserine lactone; C14:1-HSL: -tetradecenoyl-l-homoserine lactone; 3OHC14-HSL: -(3-hydroxytetradecanoyl)-l-homoserine lactone; SAM: -adenosyl-l-methionine; ACP: acyl-acyl carrier protein; EPS: extracellular polysaccharide; DMSO: dimethyl sulfoxide.
许多革兰氏阴性菌具有群体感应系统，并产生AHL作为群体感应信号分子。在本研究中，我们证明了从粉红色色素沉着的家庭生物膜中分离出的P-1M产生了两种AHL，主要产物为C14:1-HSL，次要产物为3OHC14-HSL。P-1M的完整基因组序列显示存在预测编码AHL合酶（）和AHL受体（）的基因。P-1M形成了类似菌膜的生物膜，其表面平坦且易于去除。相比之下，由和/或缺失突变体形成的生物膜具有波浪状表面结构，并强烈粘附于玻璃管。当将C14:1-HSL添加到突变体培养物中时，生物膜结构类似于野生型菌株。这些结果表明，P-1M生物膜的结构和粘附强度部分由AHL介导的群体感应决定。AHL：-酰基-l-高丝氨酸内酯；C14:1-HSL：-十四碳烯酰-l-高丝氨酸内酯；3OHC14-HSL：-（3-羟基十四烷酰基）-l-高丝氨酸内酯；SAM：-腺苷-l-甲硫氨酸；ACP：酰基-酰基载体蛋白；EPS：胞外多糖；DMSO：二甲基亚砜。
