Project/Area Number |
60560089
|
Research Category |
Grant-in-Aid for General Scientific Research (C)
|
Allocation Type | Single-year Grants |
Research Field |
応用生物化学・栄養化学
|
Research Institution | School of Agriculture, Nagoya University |
Principal Investigator |
TAKABE Tetsuko School of Agriculture, Nagoya University, 農学部, 講師 (60089852)
|
Co-Investigator(Kenkyū-buntansha) |
KOBAYASHI Hirokazu RI center, Nagoya University, アイソトープセンター, 助手 (80170348)
AKAZAWA Takashi School of Agriculture, Nagoya University, 農学部, 教授 (20023400)
|
Project Period (FY) |
1985 – 1987
|
Project Status |
Completed (Fiscal Year 1987)
|
Budget Amount *help |
¥1,600,000 (Direct Cost: ¥1,600,000)
Fiscal Year 1987: ¥100,000 (Direct Cost: ¥100,000)
Fiscal Year 1986: ¥300,000 (Direct Cost: ¥300,000)
Fiscal Year 1985: ¥1,200,000 (Direct Cost: ¥1,200,000)
|
Keywords | RuBP carboxylase / oxygenase / subunit interaction / gene expression and cloning / 塩ストレス |
Research Abstract |
(1) A DNA sequence containg genes for large and small subunits of ribulose 1, 5-bisphosphate carboxylase/oxygenase (RuBisCO) from photosynthetic purple sulfur bacterium Chromatium vinosum was cloned and sequenced. The cloned rb cLl and rbc S1 genes encode subunits of active plant-type RuBisCO which are barely expressed in Chromatium. (2) Growth of halotolerant cyanobacterium Aphanothece halopytice, previously adapted to 0.5 M NaCl, was optimal when NaCl concentration was in the range0.5-1.0 M. The growth was delayed at either too low or too high salinities with lags of ca. 0.5 day in 0.25 M NaCl and ca. 2days in 2 M NaCl under the experimental conditions. However, the growth rates at logarithmic phase were similar in the culture media containing NaCl in the range 0.25-2.0 M. The capacity of photosynthetic CO_2 fixation increased in the cells at logarithmic phase as NaCl concentration in the culture medium increased. The protein level of ribulose 1,5-bisphosphate carboxylase/oxygenase was also found to increase under high salinities using both immunoblotting method and protein A-gold immunoelectron microscopy. These results suggest that high photosynthetic capacity and high RuBisCO content may play an important role in adaptation and cellular metabolisms of Aphanothece cells grown in high salinities.
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