School of Integrative Plant Science, Section of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, New York, USA.
School of Integrative Plant Science, Section of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, New York, USA
J Bacteriol. 2019 Mar 13;201(7). doi: 10.1128/JB.00584-18. Print 2019 Apr 1.
CvsSR is a Ca-induced two-component system (TCS) in the plant pathogen pv. tomato DC3000. Here, we discovered that CvsSR is induced by Fe, Zn, and Cd However, only supplementation of Ca to medium resulted in rugose, opaque colonies in Δ and Δ strains. This phenotype corresponded to formation of calcium phosphate precipitation on the surface of Δ and Δ colonies. CvsSR regulated swarming motility in pv. tomato in a Ca-dependent manner, but swarming behavior was not influenced by Fe, Zn, or Cd We hypothesized that reduced swarming displayed by Δ and Δ strains was due to precipitation of calcium phosphate on the surface of Δ and Δ cells grown on agar medium supplemented with Ca By reducing the initial pH or adding glucose to the medium, calcium precipitation was inhibited, and swarming was restored to Δ and Δ strains, suggesting that calcium precipitation influences swarming ability. Constitutive expression of a CvsSR-regulated carbonic anhydrase and a CvsSR-regulated putative sulfate major facilitator superfamily transporter in Δ and Δ strains inhibited formation of calcium precipitates and restored the ability of Δ and Δ bacteria to swarm. Lastly, we found that glucose inhibited Ca-based induction of CvsSR. Hence, CvsSR is a key regulator that controls calcium precipitation on the surface of bacterial cells. Bacteria are capable of precipitating and dissolving minerals. We previously reported the characterization of the two-component system CvsSR in the plant-pathogenic bacterium CvsSR responds to the presence of calcium and is important for causing disease. Here, we show that CvsSR controls the ability of the bacterium to prevent calcium phosphate precipitation on the surface of cells. We also identified a carbonic anhydrase and transporter that modulate formation of surface-associated calcium precipitates. Furthermore, our results demonstrate that the ability of the bacterium to swarm is controlled by the formation and dissolution of calcium precipitates on the surface of cells. Our study describes new mechanisms for microbially induced mineralization and provides insights into the role of mineral deposits on bacterial physiology. The discoveries may lead to new technological and environmental applications.
CvsSR 是植物病原菌 pv. tomato DC3000 中的一种钙诱导的双组份系统 (TCS)。在这里，我们发现 CvsSR 被 Fe、Zn 和 Cd 诱导。然而，只有在培养基中补充 Ca 才会导致Δ和Δ菌株产生粗糙、不透明的菌落。这种表型与Δ和Δ菌落表面形成磷酸钙沉淀相对应。CvsSR 以 Ca 依赖的方式调节 pv. tomato 的群集运动，但 Fe、Zn 或 Cd 并不影响群集行为。我们假设Δ和Δ菌株显示出的群集减少是由于 Ca 补充的琼脂培养基上Δ和Δ细胞表面形成的磷酸钙沉淀所致。通过降低初始 pH 值或向培养基中添加葡萄糖，可以抑制钙沉淀，从而恢复Δ和Δ菌株的群集能力，表明钙沉淀会影响群集能力。在Δ和Δ菌株中组成性表达 CvsSR 调节的碳酸酐酶和 CvsSR 调节的假定硫酸盐主要易位超级家族转运蛋白抑制了钙沉淀的形成，并恢复了Δ和Δ细菌的群集能力。最后，我们发现葡萄糖抑制了 CvsSR 的基于 Ca 的诱导。因此，CvsSR 是控制细菌细胞表面钙沉淀的关键调节剂。细菌能够沉淀和溶解矿物质。我们之前报道了植物病原细菌中双组份系统 CvsSR 的特征，CvsSR 响应钙的存在，对引起疾病很重要。在这里，我们表明 CvsSR 控制细菌防止细胞表面形成磷酸钙沉淀的能力。我们还鉴定了一种碳酸酐酶和转运蛋白，它们调节表面相关钙沉淀的形成。此外，我们的结果表明，细菌的群集能力受细胞表面钙沉淀的形成和溶解的控制。我们的研究描述了微生物诱导矿化的新机制，并提供了对细菌生理学中矿物沉积作用的深入了解。这些发现可能为新的技术和环境应用开辟道路。
