Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky College of Medicine, Lexington, KY, USA.
J Bacteriol. 2013 Feb;195(4):757-64. doi: 10.1128/JB.01956-12. Epub 2012 Dec 7.
The Lyme disease spirochete controls production of its OspC and Erp outer surface proteins, repressing protein synthesis during colonization of vector ticks but increasing expression when those ticks feed on vertebrate hosts. Early studies found that the synthesis of OspC and Erps can be stimulated in culture by shifting the temperature from 23°C to 34°C, leading to a hypothesis that Borrelia burgdorferi senses environmental temperature to determine its location in the tick-mammal infectious cycle. However, borreliae cultured at 34°C divide several times faster than do those cultured at 23°C. We developed methods that disassociate bacterial growth rate and temperature, allowing a separate evaluation of each factor's impacts on B. burgdorferi gene and protein expression. Altogether, the data support a new paradigm that B. burgdorferi actually responds to changes in its own replication rate, not temperature per se, as the impetus to increase the expression of the OspC and Erp infection-associated proteins.
莱姆病螺旋体控制其 OspC 和 Erp 外表面蛋白的产生，在载体蜱虫的定殖过程中抑制蛋白质合成，但在这些蜱虫以脊椎动物宿主为食时增加表达。早期研究发现，通过将温度从 23°C 升高到 34°C，可以刺激 OspC 和 Erps 在培养物中的合成，这导致了一种假设，即伯氏疏螺旋体可以感知环境温度来确定其在蜱-哺乳动物感染周期中的位置。然而，在 34°C 下培养的博氏疏螺旋体比在 23°C 下培养的博氏疏螺旋体分裂速度快几倍。我们开发了将细菌生长速度和温度分开的方法，允许分别评估每个因素对伯氏疏螺旋体基因和蛋白质表达的影响。总的来说，这些数据支持了一个新的范例，即伯氏疏螺旋体实际上是对其自身复制率的变化做出反应，而不是温度本身，这是增加 OspC 和 Erp 感染相关蛋白表达的动力。
