Dubern Jean-Frédéric, Bloemberg Guido V
Section of Molecular Microbiology, Institute of Biology, Leiden University, Leiden, The Netherlands.
FEMS Microbiol Lett. 2006 Oct;263(2):169-75. doi: 10.1111/j.1574-6968.2006.00406.x.
Pseudomonas putida strain PCL1445 produces the cyclic lipopeptides putisolvin I and II, which are biosurfactants affecting environmentally important functions including swarming motility, solubility of nutrients and biofilm formation and maintenance. In this study, the effect of relevant nutritional and environmental factors on putisolvin production by PCL1445 was analyzed. Growth and levels of putisolvins I and II biosynthesis were significantly influenced by various carbon sources and by the nature of amino acid supplemented to the culture medium. An increase in the salt concentration of BM medium as well as growth at 1% oxygen significantly increased putisolvin production. In addition, we recently demonstrated that growth at a low temperature has a positive effect on putisolvin production. Analysis of the expression of gacA and gacS in Tn5luxAB mutant strains at a low temperature or under a high salt concentration suggests that biosynthesis of putisolvin is modulated through the GacA/GacS two-component regulatory system in PCL1445 under the tested conditions.
恶臭假单胞菌PCL1445菌株产生环脂肽类物质putisolvin I和II，它们是生物表面活性剂，会影响包括群体游动性、养分溶解性以及生物膜形成与维持等对环境具有重要意义的功能。在本研究中，分析了相关营养和环境因素对PCL1445产生putisolvin的影响。不同碳源以及添加到培养基中的氨基酸种类对PCL1445的生长以及putisolvin I和II的生物合成水平有显著影响。BM培养基盐浓度的增加以及在1%氧气条件下生长显著提高了putisolvin的产量。此外，我们最近证明低温生长对putisolvin的产生具有积极作用。对Tn5luxAB突变株在低温或高盐浓度条件下gacA和gacS表达的分析表明，在测试条件下，PCL1445中putisolvin的生物合成是通过GacA/GacS双组分调控系统进行调节的。
