Radziwill-Bienkowska Joanna Maria, Le Doan Thanh Lam, Szczesny Pawel, Duviau Marie-Pierre, Aleksandrzak-Piekarczyk Tamara, Loubière Pascal, Mercier-Bonin Muriel, Bardowski Jacek Karol, Kowalczyk Magdalena
Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5A, 02-106, Warsaw, Poland.
LISBP - Université de Toulouse, CNRS, INRA, INSA, Toulouse, France.
Appl Microbiol Biotechnol. 2016 Nov;100(22):9605-9617. doi: 10.1007/s00253-016-7813-0. Epub 2016 Sep 29.
Understanding the nature of mucus-microbe interactions will provide important information that can help to elucidate the mechanisms underlying probiotic adhesion. This study focused on the adhesive properties of the Lactococcus lactis subsp. cremoris IBB477 strain, previously shown to persist in the gastrointestinal tract of germ-free rats. The shear flow-induced detachment of L. lactis cells was investigated under laminar flow conditions. Such a dynamic approach demonstrated increased adhesion to bare and mucin-coated polystyrene for IBB477, compared to that observed for the MG1820 control strain. To identify potential genetic determinants giving adhesive properties to IBB477, the improved high-quality draft genome sequence comprising chromosome and five plasmids was obtained and analysed. The number of putative adhesion proteins was determined on the basis of surface/extracellular localisation and/or the presence of adhesion domains. To identify proteins essential for the IBB477 specific adhesion property, nine deletion mutants in chromosomal genes have been constructed and analysed using adhesion tests on bare polystyrene as well as mucin-, fibronectin- or collagen IV-coated polystyrene plates in comparison to the wild-type strain. These experiments demonstrated that gene AJ89_07570 encoding a protein containing DUF285, MucBP and four Big_3 domains is involved in adhesion to bare and mucin-coated polystyrene. To summarise, in the present work, we characterised the adhesion of IBB477 under laminar flow conditions; identified the putative adherence factors present in IBB477, which is the first L. lactis strain exhibiting adhesive and mucoadhesive properties to be sequenced and demonstrated that one of the proteins containing adhesion domains contributes to adhesion.
了解黏液与微生物相互作用的本质将提供重要信息，有助于阐明益生菌黏附的潜在机制。本研究聚焦于乳酸乳球菌亚种cremoris IBB477菌株的黏附特性，该菌株先前已证明能在无菌大鼠的胃肠道中持续存在。研究了层流条件下乳酸乳球菌细胞的剪切流诱导脱离。与MG1820对照菌株相比，这种动态方法表明IBB477对裸露的和黏蛋白包被的聚苯乙烯的黏附增加。为了确定赋予IBB477黏附特性的潜在遗传决定因素，获得并分析了包含染色体和五个质粒的高质量改进草图基因组序列。基于表面/细胞外定位和/或黏附结构域的存在来确定推定的黏附蛋白数量。为了鉴定对IBB477特异性黏附特性至关重要的蛋白质，构建了九个染色体基因缺失突变体，并与野生型菌株相比，在裸露的聚苯乙烯以及黏蛋白、纤连蛋白或IV型胶原包被的聚苯乙烯平板上进行黏附测试来分析。这些实验表明，编码含有DUF285、MucBP和四个Big_3结构域的蛋白质的基因AJ89_07570参与对裸露的和黏蛋白包被的聚苯乙烯的黏附。总之，在本研究中，我们表征了层流条件下IBB477的黏附；鉴定了IBB477中存在的推定黏附因子，这是首个对具有黏附和黏膜黏附特性的乳酸乳球菌菌株进行测序，并证明了其中一个含有黏附结构域的蛋白质有助于黏附。
