title: A role of nitrite reductase (NirBD) for NO homeostatic regulation in Streptomyces coelicolor A3(2).
abstract: Although nitric oxide (NO) is an important signaling molecule in bacteria and higher organisms, excessive intracellular NO is highly reactive and dangerous. Therefore, living cells need strict regulation systems for cellular NO homeostasis. Recently, we discovered that Streptomyces coelicolor A3(2) retains the nitrogen oxide cycle (NO3-→NO2-→NO→NO3-) and nitrite removal system. The nitrogen oxide cycle regulates cellular NO levels, thereby controlling secondary metabolism initiation (red-pigmented antibiotic, RED production) and morphological differentiation. Nitrite induces gene expression in neighboring cells, suggesting another role for this cycle as a producer of transmittable intercellular communication molecules. Here, we demonstrated that ammonium-producing nitrite reductase (NirBD) is involved in regulating NO homeostasis in S. coelicolor A3(2). NirBD was constitutively produced in culture independently of GlnR, a known transcriptional factor. NirBD cleared the accumulated nitrite from the medium. Nir deletion mutants showed increased NO-dependent gene expression at later culture stages, whereas the wild-type M145 showed decreased expression, suggesting that high NO concentration was maintained in the mutant. Moreover, the nir deletion mutant produced more RED than that produced by the wild-type M145. These results suggest that NO2-removal by NirBD is important to regulate NO homeostasis and to complete NO signaling in S. coelicolor.
authors: Department of Bioscience, Faculty of Applied Bioscience, Tokyo University of Agriculture, Sakuragaoka Setagaya-ku, Tokyo 156-8502, Japan.
authors: Yuriya
authors: Y
authors: Yukioka
authors: Department of Bioscience, Faculty of Applied Bioscience, Tokyo University of Agriculture, Sakuragaoka Setagaya-ku, Tokyo 156-8502, Japan.
authors: Tsukiko
authors: T
authors: Tanahashi
authors: Department of Bioscience, Faculty of Applied Bioscience, Tokyo University of Agriculture, Sakuragaoka Setagaya-ku, Tokyo 156-8502, Japan.
authors: Keisuke
authors: K
authors: Shida
authors: Department of Bioscience, Faculty of Applied Bioscience, Tokyo University of Agriculture, Sakuragaoka Setagaya-ku, Tokyo 156-8502, Japan.
authors: Haruka
authors: H
authors: Oguchi
authors: Department of Bioscience, Faculty of Applied Bioscience, Tokyo University of Agriculture, Sakuragaoka Setagaya-ku, Tokyo 156-8502, Japan.
authors: Shota
authors: S
authors: Ogawa
authors: Department of Bioscience, Faculty of Applied Bioscience, Tokyo University of Agriculture, Sakuragaoka Setagaya-ku, Tokyo 156-8502, Japan.
authors: Chiaki
authors: C
authors: Saito
authors: Department of Bioscience, Faculty of Applied Bioscience, Tokyo University of Agriculture, Sakuragaoka Setagaya-ku, Tokyo 156-8502, Japan.
authors: Shunsuke
authors: S
authors: Yajima
authors: Department of Bioscience, Faculty of Applied Bioscience, Tokyo University of Agriculture, Sakuragaoka Setagaya-ku, Tokyo 156-8502, Japan.
authors: Shinsaku
authors: S
authors: Ito
authors: Department of Bioscience, Faculty of Applied Bioscience, Tokyo University of Agriculture, Sakuragaoka Setagaya-ku, Tokyo 156-8502, Japan.
authors: Kanju
authors: K
authors: Ohsawa
authors: Department of Bioscience, Faculty of Applied Bioscience, Tokyo University of Agriculture, Sakuragaoka Setagaya-ku, Tokyo 156-8502, Japan.
authors: Hirofumi
authors: H
authors: Shoun
authors: Department of Bioscience, Faculty of Applied Bioscience, Tokyo University of Agriculture, Sakuragaoka Setagaya-ku, Tokyo 156-8502, Japan y1sasaki@nodai.ac.jp.
authors: Yasuyuki
authors: Y
authors: Sasaki
mesh_terms: D015964:Gene Expression Regulation, Bacterial; D006706:Homeostasis; D009569:Nitric Oxide / Q000378:metabolism*; D009572:Nitrite Reductases / Q000235:genetics / Q000378:metabolism*; D009573:Nitrites / Q000378:metabolism; D009584:Nitrogen / Q000378:metabolism; D015398:Signal Transduction; D048372:Streptomyces coelicolor / Q000235:genetics / Q000378:metabolism*
chemical_list: D009573:Nitrites; D009569:Nitric Oxide; D009572:Nitrite Reductases; D009584:Nitrogen
keywords: cell signaling; homeostatic regulation; nitric oxide; streptomyces