Soluble guanylate cyclase (sGC) enzyme is activated by the gaseous signaling agent nitric oxide (NO) and triggers the conversion of GTP (guanosine 5′-triphosphate) to cGMP (cyclic guanylyl monophosphate). It contains the heme binding H-NOX (heme-nitric oxide/oxygen binding) domain which serves as the sensor of NO and it is highly conserved across eukaryotes and bacteria as well. Many research studies focus on the synthesis of chemical compounds bearing possible therapeutic action, which mimic the heme moiety and activate the sGC enzyme. In this study, we report a preliminary solution NMR (Nuclear Magnetic Resonance) study of the H-NOX domain from Nostoc sp. cyanobacterium in complex with the chemical sGC activator cinaciguat (BAY58-2667). An almost complete sequence-specific assignment of its ¹H, ¹⁵N and ¹³C resonances was obtained and its secondary structure predicted by TALOS+.

可溶性鸟苷酸环化酶 (sGC) 被气态信号剂一氧化氮 (NO) 激活，并触发 GTP（鸟苷 5'-三磷酸）转化为 cGMP（环鸟苷基单磷酸）。它包含血红素结合 H-NOX（血红素一氧化氮/氧结合）结构域，用作 NO 传感器，并且在真核生物和细菌中也高度保守。许多研究重点关注具有可能治疗作用的化合物的合成，这些化合物模仿血红素部分并激活 sGC 酶。在这项研究中，我们报告了发菜 H-NOX 结构域的初步解决方案 NMR（核磁共振）研究。蓝藻与化学 sGC 激活剂 cinaciguat (BAY58-2667) 复合。获得了其¹ H、 ¹⁵ N 和¹³ C 共振的几乎完整的序列特异性分配，并通过 TALOS+ 预测了其二级结构。