Unicellular diazotrophic cyanobacteira : development of immunocytochemical methods for nitrogenase detection and analysis of their role in Kuroshio Waters.

2010 Fiscal Year Final Research Report

• Project/Area Number: 20580208
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: General fisheries
• Research Institution: Fukui Prefectural University
• Principal Investigator: OHKI Kaori Fukui Prefectural University, 海洋生物資源学部, 教授 (90101104)
• Co-Investigator(Renkei-kenkyūsha): KAMIYA Mitsunobu 公立学校法人・福井県立大学, 海洋生物資源学部, 准教授 (00281139) ; YOSHIKAWA Shinya 公立学校法人・福井県立大学, 海洋生物資源学部, 助教 (20405070)
• Project Period (FY): 2008 – 2010
• Keywords: 窒素固定 / 免疫細胞学的検出法 / 単細胞窒素固定ラン藻 / 窒素固定酵素発現 / 黒潮海域

Research Abstract

Immunocytochemical methods that is applicable for detection of unicellular diazotrophic cyanobacteria in sea waters have been developed. Using developed methods, unicellular diazotrophic cyanobacteria were detected in sea waters collected from Kuroshio waters (off Ehime Prefecture, off Miyagi prefecture and off from South Taiwan). Detection of unicellular diazotrophic cyanobacteria was also tried using DNA-amplification of nitrogenase and 16SrRNA genes. Few diazotrophic unicellular cyanobacteria were detected by both immunocytochemical and DNA-based methods in waters from off Ehime and Miyagi. Unicellular diazotrophic cyanobacteria was abundant in waters from off Taiwan : cell densities were 0.5 to 1.5×103/L. Two diazotrophic cyanobacteria were successfully isolated from off Ehime (UWA1) and Taiwan (TW3). They were identified as Gloeothece spp. (UWA1) and Cyanothece spp. (TW3) from the partial sequences of 16S rRNA and nitrogenase (nifH) genes and their morphology.

Research Products

• [Journal Article] Isolation and characterization of parmales (Heterokonta/Heterokontophyta/Stramenopiles) from the Oyashio region (2011)
  • Author(s): Ichinomiya, M. Yoshikawa, S., Kamiya,M., Ohki, K., Kuwata, A.
  • Journal Title: Western North Pacific.J. Phycol Vol.47 Pages: 144-151
  • Peer Reviewed
• [Journal Article] Seasonal variation of phlorotannin in sargassacean species from the coast of the Sea of Japan. (2010)
  • Author(s): Kamiya, M., Nishio, T., Yokoyama, A., Yatsuya, T., Nishigaki, T., Yoshikawa, S., Ohki, K.
  • Journal Title: Phycol.Res Vol.58 Pages: 53-61
  • Peer Reviewed
• [Journal Article] Detection of nitrogenase in individual cells of a natural population of Trichodesmium using immunocytochemical methods for fluorescent cells. (2009)
  • Author(s): Ohki, K., Taniuchi, Y.
  • Journal Title: J. Oceanograph Vol.65 Pages: 427-432
  • Peer Reviewed
• [Journal Article] Intercellular localization of nitrogenase in a non-heterocystous cyanobacterium (Cyanophte) Trichodesmium sp. NIBB1067. (2008)
  • Author(s): Ohki, K.
  • Journal Title: J.Oceanograph Vol.64 Pages: 211-216
  • Peer Reviewed
• [Journal Article] Whole-cell imunocytochemical detection of nitrogenase in cyanobacteria : improved protocol for higly fluorescent cells. (2008)
  • Author(s): Taniuchi, Y., Murakami, A., Ohki, K.
  • Journal Title: Aquatic Micobiol. Ecol Vol.51 Pages: 237-247
  • Peer Reviewed
• [Journal Article] Diazotrophy under continuous light in a marine unicellular diazotrophic cyanobacterium, Gloeothece 68DGA. (2008)
  • Author(s): Taniuchi, Y., Yoshikawa, S., Maeda, T., Omata, T. Ohki, K.
  • Journal Title: Microbiology Vol.154 Pages: 1859-1865
  • Peer Reviewed
• [Journal Article] Morphological and phylogenetic studies on unicellular diazotrophic cyanobacteria (Cyanophytes) isolated from the coastal waters around Singapore. (2008)
  • Author(s): Ohki, K., Kamiya, M., Honda, D., Kumazawa, S., Ho, K.K.
  • Journal Title: Vol. 44 Pages: 145-151
  • Peer Reviewed
• [Presentation] 光依存型プロトクロロフィリド還元酵素を 大量発現させたラン藻Leptolyngbya boryana の細胞生化学的解析 (2011)
  • Author(s): 山本治樹, 小島寛子, 大城香, 藤田祐一
  • Organizer: 日本植物生理学会
  • Place of Presentation: 東北大学(仙台市)
  • Year and Date: 20110300
• [Presentation] ヘテロシストを作らないラン藻 の窒素固定 (2010)
  • Author(s): 大城香
  • Organizer: シアノバクテリア談話会2010
  • Place of Presentation: 熊本大学(熊本市),招聘講演
  • Year and Date: 2010-03-20
• [Presentation] Transcriptional regulation of the nitrogen fiation related genes (nif genes) by NtcA in a unicellular cyanobacterium Gloeothece sp. 68DGA. (2009)
  • Author(s): Kawabata, T., Taniuchi T., Yoshikawa S., Kamiya, M., Ohki, K.
  • Organizer: 13th International Congress of Phototrophic Prokaryotes
  • Place of Presentation: モントリオール(カナダ)
  • Year and Date: 2009-08-10
• [Presentation] 免疫細胞学的手法を用いた窒素固定ラン藻細胞検出の試みと問題点 (2008)
  • Author(s): 大城香・谷内由貴子・吉川伸哉・ChenYhu-ling Lee
  • Organizer: 日本海洋学会秋季大会
  • Place of Presentation: 広島国際大学(呉市)
  • Year and Date: 2008-09-26