• 미생물학회지
• /
• 제8권1호
• /
• pp.1-12
• /
• 1970

Nucleic acid and protein biosynthese of the glucose-bleached Chlorella cells in relation to the process of the chloroplast reformation were traced, by measuring the changes in the amounts of cell constituents and nuclease activities of the cells during the greening process. The contents of RNA and protein of the glucose-bleached cells decreased significantly, shile the contents of nucleotides and amino acids of the cells increased to compared with those of the control, showing that the biosynthetic activities of RNA and protein of the cells were inhibited severely in the glucose-bleaching process. In the early greening process of the glucose-bleached Chlorella cells the contents of RNA and protein of the cells increased significantly, while the contents of nucleotides nad amino acids of the cells increased to compared with those of the control, showing that the biosynthetic activities of RNA and protein of the cells were inhibited severely in the glucose-bleaching process. In the early greening process of the glucose-bleached Chlorella cells the contents of RNA and protein of the cells increased significantly wihout any increase in the chlorophyll contents showing that the massive biosynthese of RNA and protein proceed prior to the chlorophyll bioynthesis in the cells. The phosphate contents in the DNA fraction of the glucose-bleached cells decreased, but the contents of acid-insoluble polyphosphate increased to compared with those of the control in the early greening porcess, exhibiting that the incorporation of the phosphorus from acid-insoluble polyphosphate into DNA was retarded. In the greening process of the glucose-bleached cells the ribonuclease nad deoxyribonuclease activities of the cells decreased to compared with those of the control, although the initial activities of the both enzymes in the cell were far great compared with the control. Although the initial phosphate contents in the lipid fraction of the glucose-bleached Chlorella cells were more great than the control, the phosphate contents in the lipid fraction of the cells decreased in the early greening process to compared with control, and then increased in the late developmental stages in which massive chlorophyll biosynthesis occured.

• 한국환경과학회지
• /
• 제2권4호
• /
• pp.255-270
• /
• 1993

녹두 유식물의 자엽에서 엽록소 및 단백질 함량과 $\delta$-aminolevulinate dehydratase(ALAD)활성의 변화에 미치는 polyamine의 영향을 조사하였다. Polyamine은 녹화과정에서 자엽내의 엽록소 생성을 촉진하였으며, 이 효과는 KCl에 의해서 상승되었다. 자엽내의 단백질 함량의 변화 또한 엽록소 함량의 변화와 유사하였다. ALAD활성은 암하에서보다 광선하에서 억제되었으나, 18시간 암처리후의 광조사는 ALAD활성을 증가시켰다. Putre-scine처리에 의한 ALAD활성은 암하에서 촉진효과가 낮았으나 광선하에는 그 활성이 증가되었다. KCl은 암하에서 ALAD활성을 촉진시켰으나 광선하에서는 그 효과가 감소되었다. 또한 polyamine과 KCl의 복합처리에서는 촉진효과가 없었다. 이와같은 결과에서 녹두자엽에서의 색소체발달은 polyamine과 광선에 의해 영향을 받으며, polya- mine은 색소체발달에 중요한 작용을 하는 것으로 사료된다.

• 한국연초학회지
• /
• 제23권2호
• /
• pp.109-114
• /
• 2001

A CAB cDNA vector(pKGCAB), encoding the light harvesting chlorophyll a/b binding protein in Korean ginseng (Panax ginseng C. A. Meyer), was constructed with the CaMV35S promoter of plant expression vector. The chimeric vector was transformed into tobacco(Nicotiana tabacum cv. NC 82) using Agrobacterium tumefaciens LBA 4404 strain, and the transgenic tobacco plant CAB-TP2 was selected. Photosynthetic rates of the CAB-TP2 plant at before-flowering stage were increased about 20% under low irradiance conditions of quantum 100 and 500 $\mu$mol.m$^{-2}$ s$^{-1}$ , however, the rates were similar to those of NC 82 under quantum 1000 and 2000 $\mu$mol.m$^{-2}$ s$^{-1}$ conditions. The plants were germinating under low- or normal irradiance condition and the quantum yield of photosystem III were measured. The differences of the Fv/Em values between conditions were 0.07 and 0.01 in NC 82 and CAB-TP2, respectively. The mature leaves in the position 8-10 of the CAB-TP2 at before-flowering stage revealed l0% higher Fv/Fm values in range of 0.759 to 0.781 and 40% more chlorophyll contents of 70-93mg/$m\ell$ than those of normal NC 82. These data suggest the possibility that the increase in photosynthetic activity of leaves under low light intensity in the canopy of CAB-TP2 transgenic tobacco might lead to increase the quality of lower tobacco leaves.

• Advances in nano research
• /
• 제3권4호
• /
• pp.243-255
• /
• 2015

In this investigation, ecotoxicity of nano and micro metal oxides, namely silica ($SiO_2$) and alumina ($Al_2O_3$), on the growth of green algae (Porphyridium aerugineum Geitler) is discussed. Effects of nano and micro particles on the growth, chlorophyll content and protein content of algae are analysed using standard protocols. Results indicate that $SiO_2$ nano and micro $SiO_2$ particles are non-toxic to P. aerugineum Geitler up to a concentration of 1000 mg/L. In addition, $Al_2O_3$ microparticles are less toxic to P. aerugineum Geitler, whereas $Al_2O_3$ nanoparticles are found to be highly toxic at 1000 mg/L. Moreover, $Al_2O_3$ nanoparticles decrease the growth, chlorophyll content, and protein content of tested algae. In addition, zeta potential and contact angle are also important in enhancing the toxicity of metal oxide nanoparticles in aquatic environment. This study highlights a new insight into toxicity evaluation of nanoparticles on beneficial aquatic organisms such as algae.

• 한국작물학회지
• /
• 제48권2호
• /
• pp.103-107
• /
• 2003

Phosphorus (P) is a macronutrient playing important roles in many plant processes. Significant interest has been devoted to search and utilize genotypic variations in P use efficiency in rice but with little effort to understand its physiological and biochemical bases. In this study, we examined responses to P deprivation of some primary and secondary traits in 3-week-old seedlings of the three genotypes, Sobi-byeo (japonica), Dasan-byeo (japonica $\times$ indica) and Palawan (indica). In general, percent weight due to root was increased up to 26%, but amounts of root protein and proteins secreted from roots were decreased by 11 to 19% and 31 to 51 %, respectively, by 3 to 21 days of P deprivation in the three genotypes. Interestingly, however, responses of Palawan to short-term P deprivation were contrasting to those of Dasan-byeo and Sobi-byeo in seedling weight and contents of shoot protein, chlorophyll and anthocyanin. Seedling weight was not decreased, but shoot protein content was decreased in P-deprived seedlings of Palawan. Contents of chlorophyll in leaves and anthocynin in roots were increased in Dasan-byeo and Sobi-byeo, but decreased in Palawan. The results suggest that responses of protein and pigment synthesis to P deficiency are different in modem and traditional varieties and the difference may at least in part be due to the selection for high yield under highly fertilized conditions.

• BMB Reports
• /
• 제34권6호
• /
• pp.496-501
• /
• 2001

Lincomycin, an inhibitor of plastid protein synthesis, was found to block the synthesis of apoprotein P700 with a molecular mass of 72 kDa and the assembly of the Chl a-protein of PS I. Synthesis of the polypeptides of 48, 43.5, and 32 kDa of the PS II complex is also suppressed. This process is accompanied by the disappearance of the PS Two reaction center Chl a at 683 nm, and of the PS One reaction center Chl a at 690, 696, and 705 nm on the fourth derivative of the absorption spectra at 77K. Lincomycin does not affect the synthesis of LHC subunits. It increases the content of the two main Chl forms of LHC at 648 nm (Chl b) and 676 nm (Chl a). The low-temperature fluorescence ratio F736/F685 is also increased. However, the effect of cycloheximide (an inhibitor of cytoplasmic protein synthesis) leads to the reduction of polypeptides of the light-harvesting Chl a/b-protein complex in the range of 29.5-22 kDa. Under these conditions, the relative amount of Chl b and the F736/ F685 fluorescence ratio decrease significantly. This is obviously the result of blocking the LHC I and LHC II synthesis. At the same time rifampicin and actinomycin D (inhibitors which block transcription in chloroplast and nuclear genome, respectively) inessentially affect the characteristics of these complexes.

• Molecules and Cells
• /
• 제38권5호
• /
• pp.390-395
• /
• 2015

Degradation of chlorophyll (Chl) by Chl catabolic enzymes (CCEs) causes the loss of green color that typically occurs during senescence of leaves. In addition to CCEs, STAYGREEN1 (SGR1) functions as a key regulator of Chl degradation. Although sgr1 mutants in many plant species exhibit a staygreen phenotype, the biochemical function of the SGR1 protein remains elusive. Many recent studies have examined the physiological and molecular roles of SGR1 and its homologs (SGR2 and SGR-LIKE) in Chl metabolism, finding that these proteins have different roles in different species. In this review, we summarize the recent studies on SGR and discuss the most likely functions of SGR homologs.

• BMB Reports
• /
• 제50권7호
• /
• pp.343-344
• /
• 2017

Plants are able to recognize even small changes in surrounding temperatures to optimize their growth and development. At warm temperatures, plants exhibit diverse architectural adjustments, including hypocotyl and petiole elongation, leaf hyponasty, and reduced stomatal density. However, it was previously unknown how such warm temperatures affected the early stages of seedling development. In our recent study, we demonstrated that the RNA-binding protein, FCA, is critical for sustaining chlorophyll biosynthesis during early seedling development, which is a prerequisite for autotrophic transition at warm temperatures. FCA plays a dual role in this thermal response. It inhibits the rapid degradation of protochlorophyllide oxidoreductases (PORs) that mediate chlorophyll biosynthesis. In addition, it induces the expression of POR genes at the chromatin level, which contributes to maintaining functional enzyme levels. Our findings provide molecular basis for the thermal adaptation of chlorophyll biosynthesis during the early stages of seedling development in nature.

• 식물조직배양학회지
• /
• 제28권1호
• /
• pp.41-45
• /
• 2001

CAB 유전자로 형질전환된 담배 2세대 식물체의 도입된 CAB 유전자 존재여부를 genomic PCR 방법으로 각계통에서 확인하였다. CAB유전자로 형질전환된 2세대 식물체를 자연 광 조건과 90% 차광된 온실에서 각각 생육시킨 결과 형질전환 식물체의 광합성능 정도는 정상 식물체와 유사하거나 약간 높은 경향이었으며, 광포화점은 형질전환 담배 식물체나 정상 식물체 모두 500$\mu$mol m$^{-2}$ s$^{-1}$로 차이가 없었다. 조사한 7계통 중 C7, C11, C14 계통의 광합성 정도가 조사된 모든 광량에서 정상 담배 식물체보다 높게 나타났다. 차광된 조건에서 생육한 담배 식물체의 광합성능 정도는 조사된 7계통 중 C2, C11, C14 계통이 90% 차광된 온실조건에서도 광합성 능이 우수하게 나타났다. 형질전환 담배 식물체의 chlorophyll 함량은 정상 NC82와 차이가 없었으며, 양지에서 생육한 조건과 90% 차광된 조건 모두에서 차이점이 없었으며 광합성능과 chlorophyll 함량과의 유의성은 없었다. 형질전환 담배 식물체 수확엽의 건물률은 정상 식물체와 비교하여 차이점이 나타나지 않았으며, 내용성분도 nicotine, 전당, 전질소에서 차이가 없었다.

• 한국식품저장유통학회지
• /
• 제13권5호
• /
• pp.655-660
• /
• 2006

유기재배법이 배추의 화학적 품질특성에 미치는 영향을 규명하기 위하여, 유기와 일반 재배 배추의 영양 및 기능성성분의 함량을 각각 비교분석 하였다. 일반성분 중 수분은 유기농 배추보다 일반배추에서 높은 함량을 나타내었으나 조단백질, 조지방, 탄수화물 및 조회분은 일반배추보다 유기농배추에서 높은 함량을 나타내었다. 수용성 및 불용성식이섬유, ascorbic acid 및 dehydroascorbic acid, chlorophyll a 및 b, carotenoid 등의 각 함량은 일반배추보다 유기농배추에서 높게 나타났다. 무기질 중 칼륨함량은 유기농배추보다 일반배추에서 높았으나 칼슘, 인, 철, 마그네슘, 황 및 아연의 함량은 일반배추보다 유기농배추에서 높게 나타났다. 유리당인 fructose, glucose 및 sucrose의 각 함량은 유기농배추에서 높았으나 유기산인 malic acid와 citric acid의 함량은 유기농배추에서 낮게 나타났다.