The alternative streptococcal σ-factor and master competence regulator, σX, stimulates transcription from competence promoters, in vitro. As the only known alternative σ-factor in streptococci, σX expression is tightly controlled in each species and has a specific physiological role. Pneumococcal transformation also requires the DNA binding activity of ComW, a known σX activator and stabilizer. Mutations to the housekeeping σ factor, σA, partially alleviate the ComW requirement, suggesting that ComW is a key player in the σ factor swap during the pneumococcal competence response. However, there is no evidence of a direct ComW - RNA polymerase interaction. Furthermore, if and how ComW functions directly at combox promoters is still unknown. Here we report that a DNA-binding ComW variant, ComΔ6, can stimulate transcription from σX promoters in vitro.

中文翻译：

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ComWΔ6 在体外刺激肺炎球菌活性基因的转录。


另一种链球菌 σ 因子和主能力调节因子 σX 在体外刺激能力启动子的转录。作为链球菌中唯一已知的替代 σ 因子，σX 表达在每个物种中受到严格控制，并具有特定的生理作用。肺炎球菌转化还需要 ComW（一种已知的 σX 激活剂和稳定剂）的 DNA 结合活性。管家 σ 因子 σA 的突变部分缓解了 ComW 的要求，表明 ComW 是肺炎球菌能力反应期间 σ 因子交换的关键角色。然而，没有证据表明 ComW - RNA 聚合酶存在直接相互作用。此外，ComW 是否以及如何直接在组合启动子上发挥作用仍然未知。在这里，我们报道了 DNA 结合 ComW 变体 ComΔ6 可以在体外刺激 σX 启动子的转录。