• Title/Summary/Keyword: Ca2+ photosynthesis

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Differential Expression of Three Novel Carbonic Anhydrases (CAs) Genes in Marine Dinoflagellate Prorocentrum minimum Against Various pH Conditions (해양 와편모조류 Prorocentrum minimum 기원 신규 탄산무수화효소(CAs) 유전자 3종의 차등 pH 대응 발현)

  • Shin, Jeongmin;Lee, Ha-Eun;Kim, Han-Sol;Ki, Jang-Seu
    • Ocean and Polar Research
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    • v.44 no.3
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    • pp.209-220
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    • 2022
  • Carbonic anhydrase (CA) is a key controller of the carbon concentrating mechanism (CCM), and is known to be affected by ambient pH and CO2 compositions. Herein, we characterized three novel CAs genes (PmCA1, 2, and 3) from the marine dinoflagellate Prorocentrum minimum, and evaluated the relative expressions of the PmCAs and photosynthetic genes PmatpB and PmrbcL under different pH conditions. Each PmCA was predicted to have amino acid residues constituting the zinc binding site. With signal peptide, PmCA1 and PmCA2 were predicted to be intracellular CAs located in the cytoplasm and chloroplast membrane, respectively. On the other hand, PmCA3 was predicted to be extracellular CA located in the plasma membrane. Also, PmCA1 was classified into the beta family, and PmCA2 and PmCA3 were classified into the alpha family via phylogenic analysis. The photosynthesis efficiency of P. minimum was similar at pH 7 to 9, and decreased significantly at pH 6 and pH 10. Overall, relative gene expression levels of the three PmCAs decreased at low pH, and increased as pH increased. Photosynthesis related genes, PmatpB and PmrbcL, showed similar expression patterns to those of PmCAs. These results suggest that changes in seawater pH may affect photosynthesis and CO2 metabolism in marine dinoflagellates.

Species-specific responses of temperate macroalgae with different photosynthetic strategies to ocean acidification: a mesocosm study

  • Kim, Ju-Hyoung;Kang, Eun Ju;Edwards, Matthew S.;Lee, Kitack;Jeong, Hae Jin;Kim, Kwang Young
    • ALGAE
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    • v.31 no.3
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    • pp.243-256
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    • 2016
  • Concerns about how ocean acidification will impact marine organisms have steadily increased in recent years, but there is a lack of knowledge on the responses of macroalgae. Here, we adopt an outdoor continuous-flowing mesocosm system designed for ocean acidification experiment that allows high CO2 conditions to vary with natural fluctuations in the environment. Following the establishment of the mesocosm, five species of macroalgae that are common along the coast of Korea (namely Ulva pertusa, Codium fragile, Sargassum thunbergii, S. horneri, and Prionitis cornea) were exposed to three different CO2 concentrations: ambient (×1) and elevated CO2 (2× and 4× ambient), over two-week period, and their ecophysiological traits were measured. Results indicated that both photosynthesis and growth exhibited species-specific responses to the different CO2 concentrations. Most notably, photosynthesis and growth increased in S. thunbergii when exposed to elevated CO2 conditions but decreased in P. cornea. The preference for different inorganic carbon species (CO2 and HCO3), which were estimated by gross photosynthesis in the presence and absence of the external carbonic anhydrase (eCA) inhibitor acetazolamide, were also found to vary among species and CO2 treatments. Specifically, the two Sargassum species exhibited decreased eCA inhibition of photosynthesis with increased growth when exposed to high CO2 conditions. In contrast, growth of U. pertusa and C. fragile were not notably affected by increased CO2. Together, these results suggest that the five species of macroalgae may respond differently to changes in ocean acidity, with species-specific responses based on their differentiated photosynthetic acclimation. Understanding these physiological changes might allow us to better predict future changes in macroalgal communities in a more acidic ocean.

Effects of future climate conditions on photosynthesis and biochemical component of Ulva pertusa (Chlorophyta)

  • Kang, Eun Ju;Kim, Kwang Young
    • ALGAE
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    • v.31 no.1
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    • pp.49-59
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    • 2016
  • Ulva pertusa, a common bloom-forming green alga, was used as a model system to examine the effects of elevated carbon dioxide (CO2) and temperature on growth and photosynthetic performance. To do this, U. pertusa was grown under four temperature and CO2 conditions; ambient CO2 (400 μatm) and temperature (16℃) (i.e., present), elevated temperature only (19℃) (ET; i.e., warming), elevated CO2 only (1,000 μatm) (EC; i.e., acidification), and elevated temperature and CO2 (ET and EC; i.e., greenhouse), and its steady state photosynthetic performance evaluated. Maximum gross photosynthetic rates (GPmax) were highest under EC conditions and lowest under ET conditions. Further, ET conditions resulted in decreased rate of dark respiration (Rd), but growth of U. pertusa was higher under ET conditions than under ambient temperature conditions. In order to evaluate external carbonic anhydrase (eCA) activity, photosynthesis was measured at 70 μmol photons m−2 s−1 in the presence or absence of the eCA inhibitor acetazolamide (AZ), which inhibited photosynthetic rates in all treatments, indicating eCA activity. However, while AZ reduced U. pertusa photosynthesis in all treatments, this reduction was lower under ambient CO2 conditions (both present and warming) compared to EC conditions (both acidification and greenhouse). Moreover, Chlorophyll a and glucose contents in U. pertusa tissues declined under ET conditions (both warming and greenhouse) in conjunction with reduced GPmax and Rd. Overall, our results indicate that the interaction of EC and ET would offset each other’s impacts on photosynthesis and biochemical composition as related to carbon balance of U. pertusa.

Effects of Antioxidants on the Photoinhibition in Panax ginseng C.A. Meyer (인삼의 광억제(Photoinhibition)에 대한 항산화제의 처리효과)

  • 양덕조;김명원
    • Journal of Ginseng Research
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    • v.17 no.3
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    • pp.232-235
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    • 1993
  • We investigated the effect of antioxidants (ascorbate, glutathione, and sodium azide), which efEectively inhibited the chlorophyll bleaching of Panax ginseng CA Meyer under the high light intensity, treated by folilar wiping on the early stage of photosynthesis and transpiration of ginseng in the 5000 $\mu$mol photon.$m^{-2}$.$s^{-1}$. Ascorbate and glutathione, endogenous antioxidant, completely recovered ginseng from the photoinhibition, but sodium azide, synthetic quencher, showed negative effect. We assumed that endogenous antioxidants could be available to the protection of the leaf-burning phenomenon of ginseng.

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The Mechanism of Stomatal Closing by $H_2O_2$ in Epidermal Strips of Commelina communis L. (닭의장풀의 분리표피에서 $H_2O_2$에 의한 기공 닫힘기작)

  • 이준상;전방욱
    • Journal of Environmental Science International
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    • v.6 no.2
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    • pp.125-131
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    • 1997
  • The mechanism of stomatal closing in response to $O_2$ was indirectly investigated by using $H_2O_2$ which is the intermediate product of $O_2$ metabolites. Stomata in epidermal strips close in response to $H_2O_2$. The effect of $H_2O_2$ on stomatal closing was dependent on the concentration of $H_2O_2$. 10 ppm $H_2O_2$ showed a clear effect on stomatal closing and 1000 ppm $H_2O_2$ induced complete stomatal closing after the treatment of 3 hours. Stomatal closing by $H_2O_2$ in intact leaf was also observed by measuring the diffusion resistance with porometer. It was found that the stomatal closing by $H_2O_2$ was not mediated by $Ca^{2+}$, and that was a different result observed in stomatal closing by water stress. Reversely, $Ca^{2+}$ showed a great inhibition on stomatal closing. The leakage of K+ in epidermal strips was doubled in response to $H_2O_2$ when it was campared to the control. 10 ppm $H_2O_2$ decreased photosynthetic activity. Fv/Fm representing the activity of Photosystem II was reduced about 4 % in 10 ppm $H_2O_2$ and 8 % in 100 ppm $H_2O_2$ In the treatment of 1.5 hour. However, stomatal closing by 10 ppm $H_2O_2$ was reduced about 56 %. According1y, it can be suggested that stomatal closing by $H_2O_2$ is related with the decrease of photosynthetic activity, but it was chiefly induced by the change of the membrane permeability. Key words Commelina communis, stomatal closing, $H_2O_2$, $Ca^{2+}$, photosynthesis.

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Effects of Relative Humidity Levels on Ion Leakage, Photosynthesis, Stomatal Resistance, Water Use Efficiency and Growth in Cos Lettuce 'Manavert' (습도 조건이 Cos Lettuce의 전해질, 광합성, 기공저항, 수분이용 효율 및 생육에 미치는 영향)

  • 최기영;김남영;박미희;이용범
    • Proceedings of the Korean Society for Bio-Environment Control Conference
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    • 1998.10a
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    • pp.111-114
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    • 1998
  • 상추의 Ca 결핍으로 인한 생리 장해인 tipburn은 \circled1 배지 중의 Ca이 부족했을 때 \circled2 배지 중 Ca 은 충분하나 여러 원인에 의해서 Ca 흡수가 억제될 때, 또는 \circled3흡수 및 지상부로의 이동은 어느 정도 이루어지나 필요한 부위로의 충분한 공급이 이루어지지 않을 때 또는 필요량이 많아 공급이 부족할 때 등이다. 본 실험은 지상부로의 Ca 이동에 영향을 미치는 인자 중 습도 조건을 달리 했을 때의 막투과성의 변화와 기공반응 및 생육에 미치는 영향을 살펴봄으로써 상추의 Ttpburn 발생에 미치는 습도의 영향을 알아보고자 실시하였다. (중략)

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Stomatal Response by Ozone (오존에 대한 식물 기공 반응고찰)

  • 이준상;김병우
    • The Korean Journal of Ecology
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    • v.20 no.2
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    • pp.83-94
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    • 1997
  • Stomatal closing by ozone and water stress could reduce further ozone injury by inhibition of ozone influx to the tissue. Direct effect of ozone on stomata can be explained from two aspects which are a stimulation of stomatal closing and an inhibition of stomatal opening. An increase of $Ca^{2+}$ influx into cytoplasm by ozone could stimulate potassium efflux ion channel and inhibits inward potassium ion channels. By this mechanism ozone could induce stomatal closing. On the other hand, ozone could inhibit stomatal opening by affecting the activity of $H^{+}$ dependent ATPase of the membrane in guard cells. This would inhibit proton efflux which precede stomatal opening. It is also possible that ozone could reduce the activity of photosynthesis in guard cells which lead to affect the production of osmotically active sugars and energy. Indirect effect of ozone to stomata is through the effect of $CO_2$ elevation as a result of damage of the photozynthetic machinery. This indirect effect is slower than the direct effect.

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Photo-autotrophic Behavior of Engineered Living Building Materials (Living Building Material의 광합성 작용을 통한 CO2 흡수 능력 평가)

  • Jang, Indong;Yi, Chongku
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2022.11a
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    • pp.31-32
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    • 2022
  • Unlike conventional building materials, the living building material (LBM) cube is composed of sand, gelatin, and cyanobacteria without cement. The surface of the LBM cube absorbs CO2 from the atmosphere by photosynthesis and is deposited in the form of CaCO3. In addition, the crystals generated in this process strengthened the gelatin-sand structure to enhance the compressive strength.

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Relation between Temperature and Growth of Sweet Pepper by Growing Areas in Greenhouse (온실 내 위치에 따른 온도 환경과 착색단고추 생육과의 관계)

  • Park, Su-Min;Kim, Ho Cheol;Ku, Yang Gyu;Kim, Sang Wook;Bae, Jong Hyang
    • Horticultural Science & Technology
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    • v.30 no.6
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    • pp.680-685
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    • 2012
  • The objective of the experiment was to investigate the effect of two growing areas in the greenhouse on the plant growth characteristics, physiological responses and yield attributes of the 'Cupra' sweet pepper. Two growing areas of the greenhouse were as follows, central part area (CA) and north part area (NA). Daily average temperature of the CA was $1.6^{\circ}C$ higher than those of NA. Plant height, number of internode, and SPAD value in the CA were significantly higher than NA both six weeks and twelve weeks after planting. Net photosynthesis of the sweet pepper leaves of the CA was significantly higher than those of NA. The total fruit yield of the sweet pepper was 20% higher in plants grown for CA than that of NA. These results suggest that air temperature in the greenhouse influenced plant growth characteristics, net photosynthesis and total yield of sweet pepper whether pepper plants were grown as CA or as NA.

Effect of GeO2 on embryo development and photosynthesis in Fucus vesiculosus (Phaeophyceae)

  • Tarakhovskaya, Elena R.;Kang, Eun-Ju;Kim, Kwang-Young;Garbary, David J.
    • ALGAE
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    • v.27 no.2
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    • pp.125-134
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    • 2012
  • Germanium dioxide ($GeO_2$) has been used for many years in the cultivation of red and green algae as a means of controlling the growth of diatoms. Brown algae are sensitive to $GeO_2$, however, the basis of this sensitivity has not been characterized. Here we use embryos of $Fucus$ $vesiculosus$ to investigate morphological and physiological impacts of $GeO_2$ toxicity. Morphometric features of embryos were measured microscopically, and physiological features were determined using pulse amplitude modulated (PAM) fluorometry. At 5 mg $L^{-1}$ $GeO_2$, embryos grew slower than controls and developed growth abnormalities. After 24 h, initial zygote divisions were often oblique rather than transverse. Rhizoids had inflated tips in $GeO_2$ and were less branched, and apical hairs were deformed, with irregularly aligned, spheroidal cells. Minimum fluorescence ($F_0$) showed minor differences over the 10 days experiment, and pigment levels (chlorophylls $a$, $c$ and total carotenoids) showed no difference after 10 days. Optimum quantum yield increased from ca. 0.52 at 24 h to 0.67 at 5 days, and $GeO_2$-treated embryos had higher mean values (significant at 3 and 5 days). Optimum quantum yield of photosystem II (${\Phi}_{PSII}$) was stable in control thalli after 5 days, but declined significantly in $GeO_2$. Addition of silica (as $SiO_2$) did not reverse the effects of $GeO_2$. These results suggest that $GeO_2$ toxicity in brown algae is associated with negative impacts at the cytological level rather than metabolic impacts associated with photosynthesis.