A cellular slime mold, Dictyostelium discoideum, is an amoeboid organism that has a unique life cycle consisting of distinctly separated vegetative and developmental phases. Thus, this organism presents a rare opportunity in which to examine the effects of bioactive substances on separate cellular activities. In this research, we investigated the effect of a culture extract, termed EMXG, produced by a synthetic microbial consortium. EMXG promoted proliferative response of amoeba cells. It further accelerated the developmental phase, leading to the preferred fruiting body formation from fewer cells. Furthermore, EMXG modulated biological rhythm of this organism, that is, interval of oscillation of cAMP level observed in suspension starvation was significantly shortened. Concomitantly, the level of ERKB, a MAP kinase, was found to oscillate in a similar fashion to that of cAMP. Additionally, ErkB-deficient mutant amoeboid cells did not respond to proliferative stimulation by EMXG. These lines of evidence point to a likelihood that MAP kinase cascade is involved and further that ErkB could be the molecular target of EMXG.
J Mol Microbiol Biotechnol

中文翻译：

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通过合成微生物联合会生产的培养物提取物，通过MAP激酶级联加快了盘基网柄菌的生命周期。

细胞粘液霉菌，盘基网柄菌，是一种具有独特生命周期的变形虫生物，其生命周期由明显不同的营养阶段和发育阶段组成。因此，该生物体提供了难得的机会来检查生物活性物质对单独的细胞活动的影响。在这项研究中，我们调查了由合成微生物联盟生产的称为EMXG的培养物提取物的作用。EMXG促进了变形虫细胞的增殖反应。它进一步加速了发育阶段，从较少的细胞中形成了优选的子实体。此外，EMXG调节了该生物的生物节律，即在悬浮饥饿中观察到的cAMP水平的振荡间隔大大缩短了。同时，发现MAP激酶ERKB的水平以与cAMP类似的方式振荡。另外，缺乏ErkB的突变型变形虫细胞对EMXG的增殖刺激无反应。这些证据表明，有可能参与了MAP激酶级联反应，并且进一步表明ErkB可能是EMXG的分子靶标。
微生物微生物学杂志