Heme is involved in signal transduction by either acting as a cofactor of heme-based gas/redox sensors or binding reversely to heme-responsive proteins. Bacteria respond to low concentrations of nitric oxide (NO) to modulate group behaviors such as biofilms through the well-characterized H-NOX family and the newly discovered heme sensor protein NosP. NosP shares functional similarities with H-NOX as a heme-based NO sensor; both regulate two-component systems and/or cyclic-di-GMP metabolizing enzymes, playing roles in processes such as quorum sensing and biofilm regulation. Interestingly, aside from its role in NO signaling, recent studies suggest that NosP may also sense labile heme. In this Highlight Review, we briefly summarize H-NOX-dependent NO signaling in bacteria, then focus on recent advances in NosP-mediated NO signaling and labile heme sensing.

中文翻译：

---

血红素传感器蛋白 NosP 和 H-NOX 对多因素生物膜调节的最新证据

血红素通过充当基于血红素的气体/氧化还原传感器的辅助因子或与血红素反应蛋白反向结合来参与信号转导。细菌通过充分表征的 H-NOX 家族和新发现的血红素传感器蛋白 NosP 对低浓度的一氧化氮 (NO) 作出反应，以调节生物膜等群体行为。NosP 与 H-NOX 作为基于血红素的 NO 传感器具有功能相似性；两者都调节双组分系统和/或环状二-GMP代谢酶，在群体感应和生物膜调节等过程中发挥作用。有趣的是，除了它在 NO 信号传导中的作用外，最近的研究表明，NosP 也可能感知不稳定的血红素。在这个亮点回顾，我们简要总结了细菌中 H-NOX 依赖性 NO 信号传导，然后重点介绍了 NosP 介导的 NO 信号传导和不稳定血红素传感的最新进展。