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1.
Herein, we conducted a study toward understanding the impact of composting of the diesel-contaminated soil with some locally available bulking agents (rice husks (RHs), sawdust (SD), and wood chips (WCs)). In order to ascertain the effectiveness of petroleum degradation by the process assayed, we compared the protocols with monitored natural attenuation (MNA). The overall degradation pattern was modeled with non-linear regression by comparing the experimental data with first and second-order kinetic equations. At the end of the six-week study, the amount of total petroleum hydrocarbon removed from contaminated soil was 98.26 ± 1.33% (amendment with SD + RHs + WCs), 96.89 ± 1.20 (RHs amendment), 96.55 ± 1.29% (amendment with SD), 90.01 ± 0.22% (WCs amendment), and 85.02 ± 0.21% (MNA). The degradation of TPH trends followed a second-order kinetic model for all the four compost treatments while the MNA was found to follow a first-order (slower) degradation pattern. In general, the results of the parameter estimate showed that amendment with mixture of the three bulking agents was 1.08 (8%) slower (k2 = (1.289 ± 0.16) × 10?5 (g mg?1 d?1), r2 = 0.991) than SD amendment alone (k2 = (1.392 ± 0.14) × 10?5 (g mg?1 d?1), r2 = 0.995). However, the mixture of the bulking agents was found to be 1.67, 1.41, and 2.4 times faster than amendments with WCs, rice, and MNA, respectively. The phytotoxicity test revealed that all the compost treatments except WCs resulted in germination index of ≥80% after six weeks of bioremediation tests. The outcome of the current investigation confirms the effectiveness of bulking agents (especially when combined) in the supply of nutrients for the bioremediation of diesel-impacted soil.  相似文献   

2.
The effects of the injection of a large amount of N1 -methylnicotinamide (MNA) (500 mg per kg body weight) on the ratio of N1 -methyl-4-pyridone-3-carboxamide (4-py) to N1 -methyl-2-pyridone-5- carboxamide (2-py) excretion, and the activities of 2-py and 4-py forming MNA oxidases were investigated in rats. The injected MN A was excreted very rapidly into the urine; 46 % of the dose was excreted from 0~3hr post-injection, 15% from 3~6hr, 6% from 6~9hr and 1.5% from 9~ 12hr. The ratio of 4-py to 2-py also decreased rapidly; the ratio being about 0.6, 0.4, 0.4 and 0.6 from 0~3hr, 3~6hr, 6~9hr and 9~ 12hr post-injection, respectively. This ratio then recovered rapidly; being about 2, 5.5, 8.5 and 9.7 from 12~24 hr, 24 ~48 hr, 48~72 hr and 72 ~96 hr post-injection, respectively. The normal range of 4-py to 2-py excretion ratio is 8~14. So, this ratio returned to a normal level by day 3 post-injection. The rats were killed 5 hr after the MNA injection. At this time (the lowest ratio was observed around this time), the activities of 2-py and 4-py forming MNA oxidases in the injected group were 59 % and 11 % of the normal levels, respectively. Therefore, it was found that the decreased ratio of 4-py to 2-py excretion with the MNA injection was mainly due to the higher inhibition of the 4-py forming MNA oxidase than of the 2-py forming MNA oxidase by the MNA injection.  相似文献   

3.
doi: 10.1111/j.1741‐2358.2012.00651.x Oral health‐related quality of life and nutritional status of institutionalized elderly population aged 60 years and above in Mysore City, India Objective: To assess whether oral health–related quality of life (OHRQoL) is associated with nutritional status in the institutionalised elderly population of Mysore. Background: Malnutrition in the elderly has an evident impact on their general health and quality of life. Analysis of data of the Geriatric Oral Health Assessment Index (GOHAI) and their association with the Mini Nutritional Assessment (MNA) results improves our understanding of the complex relationship between oral health and malnutrition. Materials and methods: The study was conducted among the institutionalised elderly population in Mysore city, Karnataka. Data on socio‐demographic, oral health status were gathered. OHRQoL was evaluated using GOHAI, and malnutrition risk using MNA. Results: Out of 141 elderly, 41.1% were men and 58.9% were women with mean age of 72.2 ± 7.5 years. Mean GOHAI score was 47.03 ± 9.2, with 69.5% had low perception of oral health. Mean MNA score was 9.91 ± 2.4, 15.6% were malnourished, 52.5% were at risk of malnutrition and 31.9% were adequately nourished. A strong association was found between the mean GOHAI and MNA scores. Conclusion: Oral health–related quality of life was associated with nutritional deficit, and it requires a greater integration between dentistry and nutrition in the health promotion of older adults.  相似文献   

4.
Abstract

Objectives

This study was focused on the monitoring how the anti-inflammatory substance, N1-methylnicotinamide (MNA), could influence oxidation and glycooxidation stress markers in rats under conditions of streptozotocin (STZ)-induced diabetes mellitus.

Methods

Diabetes mellitus was induced in 60 male Wistar rats by intraperitoneal injection of STZ and after 7 days diabetic animals were allocated to five groups according to the dose of MNA administered for 7 weeks. The degree of DNA damage in lymphocytes, as well as advanced glycation endproducts (AGEs), protein carbonyls, lipid peroxides, and total antioxidant capacity (TEAC) in plasma were measured.

Results

Glycation damage to proteins (represented by AGEs level) was significantly increased in all diabetic groups compared to untreated non-diabetic animals. MNA did not affect TEAC of plasma in any group of diabetic rats. Supplementation of diabetic rats with MNA at the dose of 200 mg/kg resulted in decreased protein carbonyls (from 0.0818 ± 0.0091 to 0.0558 ± 0.0044 nmol/mg proteins; P < 0.05, n = 15) and DNA oxidation, reflected by the levels of 8-oxoG (0.6302 ± 0.085 vs. 0.9213 ± 0.108 8-oxoG/106 G; P < 0.05, n = 15), compared to untreated diabetic animals.

Discussion

Our results demonstrated that MNA at suitable concentrations could influence oxidative modifications of proteins and DNA.  相似文献   

5.
The effects of ethanol feeding on the tryptophan-niacin metabolism were investigated in rats. Male rats of the Wistar strain (3 weeks old) were fed with a 20% casein diet and 15% ethanol ad libitum for 56 days. Urine samples were collected every week during the experimental period. Urinary excretion of N1-methylnicotinamide (MNA) was always higher in the ethanol-fed group than in the control group, but urinary excretion of its oxidized metabolites N1-methyl-2-pyridone-5-carboxamide (2-Py) and N1-methyl-4-pyridone-3-carboxamide (4-Py) was always lower. Therefore, the ratio of (2-Py + 4-Py)/MNA excretion was lower in the ethanol-fed group than in the control group. The rats were killed on day 57 and liver enzyme activities involved in the tryptophan-niacin metabolism were also measured. Tryptophan oxygenase, kynureninase, nicotinamide mononucleotide adenylyltransferase, NAD+ synthetase, and nicotinamide methyltransferase activities were similar in both groups, but, 2-Py-forming MNA oxidase and 4-Py-forming MNA oxidase activities in the ethanol-fed group were 43% and 18% of the control, respectively. Therefore, the increase in MNA excretion and the decrease in the ratio of (2-Py + 4-Py)/MNA excretion might be attributed to the inhibition of the two MNA oxidase activities by ethanol feeding. Furthermore, it happened to be found that this excretion ratio also increased with growth up to nine weeks and this change was attributed to the increased reaction MNA → 4-Py with growth.  相似文献   

6.
The effects of jasmonic acid (JA) on secondary metabolism in barley (Hordeum vulgare L.) were investigated. A reversed-phase HPLC analysis revealed that the amount of a particular compound increased in excised barley leaf segments that had been treated with JA. This compound was purified and identified as 6´´´-feruloylsaponarin (1) by spectroscopic analyses and alkaline hydrolysis. A related compound, 6´´´-sinapoylsaponarin (2), was also found to accumulate in excised leaves independently of the JA treatment. The accumulation of these compounds was accompanied by a decrease in the saponarin (3) content. [8,9-13C]p-Coumaric acid and [2,3,4,5,6-2H]L-phenylalanine were effectively incorporated into the hydroxycinnamoyl moieties in 1 and 2, while the degree of incorporation of the labeled precursors into the saponarin part was small. These findings indicate that the hydroxycinnamoyl moieties of 1 and 2 are synthesized de novo from phenylalanine via the phenylpropanoid pathway, and that the saponarin part is mainly provided by the constitutive pool of 3.  相似文献   

7.
Objective: Large portions increase intake and are hypothesized to contribute to the obesity epidemic. However, it is unclear if portion size affects intake through changes in the unit size of available food or the overall amount of food available for consumption. Thus, this study examined the independent effects of package unit size and amount of food on intake. It was hypothesized that both variables would influence intake. Research Methods and Procedures: Non‐obese (BMI <30 kg/m2), non‐smoking, unrestrained, college‐aged men (n = 12) and women (n = 16) who regularly consumed (≥3 times/wk) snack foods were randomly assigned to one of four groups crossing package unit size (small vs. large) and amount of food (small vs. large). Participants were given a box with 4 snack foods (potato chips, cheese crackers, cookies, and candy) packaged according to their assigned group to take home and eat over 3 days. Dependent variables were energy and gram intake of provided snack foods. Results: An effect of amount of food was found (p < 0.01). A 100% increase in the amount of food provided produced an 81% increase in energy consumed from the snack foods [small amount, 21,037.6 ± 10,852 kJ (5028 ± 2596 kcal) vs. large amount, 11,640.7 ± 4914.1 kJ (2782 ± 1174 kcal)]. No effect of package unit size was found. Discussion: These results suggest that the amount of food available to eat strongly influences intake.  相似文献   

8.
The formation of a thrombus is a key event in thromboembolic disorders, that contribute to high mortality and morbidity in affected patients. In the present study, we synthesized a library of novel substituted 3,3-dibutyl-8-methoxy-2,3-dihydrobenzo [b] [1,4] thiazepin-4(5H)-one derivatives which were tested for their platelet aggregation and thrombin inhibitory activity. Among the tested compounds, 3,3-dibutyl-7-(2-chlorophenyl)-8-methoxy-2,3-dihydrobenzo[b] [1,4]thiazepin-4(5H)-one (DCT) displayed the maximum thrombin inhibition with an IC50 value of 3.85 μM and thus DCT was chosen for further studies. Next, the effect of DCT on primary hemostasis was evaluated using agonist-induced platelet aggregation model. The lead compound inhibited the collagen- or ADP- or thrombin-induced platelet aggregation in a dose-dependent manner. Furthermore, DCT prolonged the process of clot formation when evaluating plasma re-calcification time (320 ± 11 sec at 5 µg DCT), activated partial thromboplastin time (58.0 ± 0.01 sec at 2 µg), and prothrombin time (14.7 ± 0.01 sec at 5 µg). Molecular docking studies suggested that the benzothiazepinones evaluated here consistently display hydrogen bonding with Ser214 of thrombin, which is similar to that of the co-crystallized ligand (1-(2R)-2-amino-3-phenyl-propanoyl-N-(2,5dichlorophenyl)methylpyrrolidine-2-carboxamide). DCT displayed additional hydrogen bonding to Ser195 and π-π interactions between its methoxyphenyl groups and Trp60, thereby providing a structural rationale for the observed biological effect.  相似文献   

9.
The effect of the addition of 0.26 % free tryptophan (Trp) to a 20 % casein diet containing 6 mg of nicotinic acid per 100 g of diet on the ratio of N1-methyl-2-pyridone-5-carboxamide (2-py) plus N1-methyl-4-pyridone-3-carboxamide (4-py) to -methylnicotinamide (MNA) excretion was investigated in rats. The urinary excretion of MNA, 2-py and 4-py, respectively, increased statistically significantly with the feeding of a 0.26% Trp (the same as the content of the 20% casein diet) supplemented 20% casein diet, although it did not increase with the feeding of a 40% casein diet, compared with in the case of the 20 % casein diet [Agric. Biol. Chem., 52, 1765 (1988)]. So, the total urinary excretion of Nam and its metabolites was 1.8 times higher in the group fed the Trp supplemented diet than in the group fed the 20 % casein diet. However, the ratio of 2-py plus 4-py to MNA excretion was much lower in the group fed the Trp supplemented diet than in the group fed the 20 % casein diet (13.16 ± 3.75→5.49 ± 2.25). This decreased ratio was considered to be partially due to a decrease in the 4-py forming MNA oxidase, which decreased significantly with the feeding of the Trp supplemented diet. Furthermore, the metabolic fate of Trp was greatly affected by the form of Trp, free or bound.  相似文献   

10.
Abstract

4-pyridone-3-carboxamide-1-β-D-ribonucleoside (4PYR) is a new nicotinamide derivative, which is potentially toxic to the endothelium. Dysfunction of the endothelium promotes cancer cell proliferation, invasiveness, and inflammatory signaling. The aim of this study was to analyze 4PYR concentration in the plasma of lung cancer patients and its relationship to other known biochemical parameters associated with the endothelium function.

The concentration of 4PYR, nicotinamide, 1-methylnicotinamide (MNA), amino acids, and their derivatives were measured in samples obtained from patients with primary squamous cell carcinoma (n?=?48) and control group (n?=?100).

The concentration of 4PYR and 4PYR/MNA ratio were significantly higher in lung cancer patients as compared to controls (0.099?±?0.009 vs. 0.066?±?0.006?µmol/L and 1.10?±?0.08 vs. 1.97?±?0.15, respectively). The plasma arginine/asymmetric dimethylarginine (Arg/ADMA) ratio was considerably lower in lung cancer patients (253?±?17 vs. 369?±?19) as well as plasma MNA (0.057?±?0.004 vs. 0.069?±?0.003?µmol/L). There was no difference in the plasma concentrations of nicotinamide and nicotinamide riboside in both groups (0.116?±?0.019 vs. 0.131?±?0.014 and 0.102?±?0.006 vs. 0.113?±?0.011, respectively).

In this study, a higher 4PYR concentration was observed for the first time in patients with squamous cell carcinoma. This change may be related to the endothelial dysfunction that promote cancer progression since 4PYR and its derivatives are known to disrupt glycolytic pathway.  相似文献   

11.
doi: 10.1111/j.1741‐2358.2011.00545.x Nutritional status, dietary intake and oral quality of life in elderly complete denture wearers Background and objective: The prevalence of malnutrition increases with age because of many factors. Edentulousness leads to the avoidance of many types of foods. The aim of this study was to determine whether elderly complete denture wearers have a higher risk of malnutrition than dentate controls. Material and methods: A Mini‐Nutritional Assessment (MNA) and a 3‐day dietary record were compiled for a group of fully dentates (21 women and 29 men; mean age 70.1 ± 6.1) and for a group of complete denture wearers (31 women and 16 men; mean age 70.1 ± 8.1). Socio‐demographic data and scores on the General Oral Health Assessment Index (GOHAI) questionnaire were collected. Results: Inter‐group comparison of MNA scores showed that more subjects in the edentulous group (21.3%) risked malnutrition than in the dentate group (0%). The variability of the MNA could be explained for 22% by dental status, 7% by loneliness and 4% by the GOHAI score (regression analysis). Both groups had insufficient energy intakes and deficits in vitamins and micronutrients; moreover, edentulous subjects had lower intakes than dentate subjects. Conclusion: The use of conventional dentures increases the risk of malnutrition in the elderly.  相似文献   

12.
The steady-state pharmacokinetics in serum and urine of the enantiomers of citalopram and its metabolites, demethylcitalopram (DCT) and didemethylcitalopram (DDCT), were investigated after multiple doses of rac-citalopram for 21 consecutive days (40 mg per day) to healthy human subjects who were extensive metabolisers of sparteine and mephenytoin. Comparable pharmacokinetic variability was noted for (+)-(S)-, (−)-(R)- and rac-citalopram. Enantiomeric (S/R) serum concentration ratios for citalopram were always less than unity and were constant during the steady-state dosing interval. A modest, but statistically significant, stereoselectivity in the disposition of citalopram and its two main metabolites was observed. Serum levels of the (+)-(S)-enantiomers of citalopram, DCT, and DDCT throughout the steady-state dosing interval investigated were 37 ± 6%, 42 ± 3% and 32 ± 3%, respectively, of their total racemic serum concentrations. The (+)-(S)-enantiomers of citalopram, DCT, and DDCT were eliminated faster than their antipodes. For (−)-(R)- and (+)-(S)-citalopram, respectively, the serum t½ averaged 47 ± 11 and 35 ± 4 h and AUCss averaged 4,193 ± 1,118 h · nmol/l and 2,562 ± 1,190 h · nmol/l. The observed enantiospecificities were apparently more related to clearance, rather than to distributional mechanisms. Chirality 9:686–692, 1997. © 1997 Wiley-Liss, Inc.  相似文献   

13.
The cell membrane of Streptococcus sanguis contains three classes of lipid: neutral lipid, glycolipid and phospholipid. A striking difference in membrane lipid composition between cells in the exponential and in the stationary phases of growth was observed. During the exponential phase, approx. 37–45%, 14–19% and 37–45% of the lipids synthesized were found to be neutral lipid, glycolipid and phospholipid, respectively. The amount of lipid synthesized reached a maximum at the early stationary phase. The amount of phospholipid drastically declined thereafter and that of neutral lipid slightly declined. In contrast, the amount of glycolipid markedly increased and exceeded the amount of phospholipid. The phospholipid present during the exponential phase was found to be mainly phosphatidylglycerol (82–88%) and a small amount of cardiolipin (12–18%). At the stationary phase, the amount of phosphatidylglycerol greatly decreased and reached approx. 16% of that in the early stationary phase, while cardiolipin steadily increased and became the major phospholipid in the late stationary phase. The glycolipid was found to be composed of mainly mono- and diglucosyldiglycerides. At the end of the experiment (after 8 h incubation), the distribution of lipids was found to be: neutral lipid, 46%; glycolipid (monoglucosyldiglyceride, 28%; diglucosyldiglyceride, 13%) 41%; and phospholipid (phosphatidylglycerol, 3%, cardiolipin, 8%) 13%.  相似文献   

14.
Gerodontology 2012; doi: 10.1111/j.1741‐2358.2012.00673.x Functional tooth units and nutritional status of older people in care homes in Indonesia Objectives: To investigate the relationship between functional tooth units (FTUs) and nutritional status. Methods: One hundred females (mean age: 72.4 ± 8.2 years) at four private care homes in Jakarta, Indonesia were interviewed and clinically examined. The oral examination included the assessment of teeth, prosthetic status, and number of FTUs. The total number of FTUs was further divided by tooth composition: natural tooth against natural tooth (NN‐FTUs), natural tooth against denture (ND‐FTUs), and denture against denture (DD‐FTUs). Nutritional status was evaluated using the body mass index (BMI) and the Mini Nutritional Assessment (MNA). Results: The mean numbers of teeth present, NN‐FTUs, ND‐FTUs, DD‐FTUs, and total FTUs were 13.1 ± 10.4, 1.7 ± 3.0, 1.2 ± 3.3, 0.4 ± 1.2 and 3.3 ± 4.4, respectively. The mean BMI and MNA scores were 24.8 ± 5.0 and 22.6 ± 2.8, respectively. Subjects with a normal BMI had a significantly higher total number of FTUs (3.6 ± 4.6) compared with underweight subjects (0.1 ± 0.3). Subjects with a normal MNA had a significantly higher number of NN‐FTU (2.6 ± 3.7) compared to those who were at risk or in a state of under‐nutrition (1.2 ± 2.4). Conclusion: This study revealed significant relationships between the number of FTUs and nutritional status. Keeping the posterior occlusion should be emphasized in order to maintain good nutritional status in older subjects.  相似文献   

15.
A nucleic acid component (x-RNA) has been found in high concentration in maize shoots. It is eluted from a MAK (methylated albumin kieselguhr) column at about the same position as messenger RNA. The amount of x-RNA in pea epicotyls is absent or very low. It is suggested that x-RNA is long-lived messenger RNA and is found in high concentration in monocotyledonous plants, especially in the case of plants of the Gramineae family. Dicotyledonous plants, typically, contain little or no detectable x-RNA as observed by ultraviolet absorbancy. In the case of corn shoots, x-RNA is in highest concentration in the ribosomal fraction (78,500 × g, 70 min). In both maize shoots and pea epicotyls the newly synthesized nucleic acids were confined to the nuclear fraction (10,000 × g, 10 min).  相似文献   

16.
Protoxin II is biologically active peptide containing the inhibitory cystine knot motif. A synthetic version of the toxin was generated with standard Fmoc solid phase peptide synthesis. If N‐methylmorpholine was used as a base during synthesis of the linear protoxin II, it was found that a significant amount of racemization (approximately 50%) was observed during the process of cysteine residue coupling. This racemization could be suppressed by substituting N‐methylmorpholine with 2,4,6‐collidine. The crude linear toxin was then air oxidized and purified. Electrophysiological assessment of the synthesized protoxin II confirmed its previously described interactions with voltage‐gated sodium channels. Eight other naturally occurring inhibitory knot peptides were also synthesized using this same methodology. The inhibitory potencies of these synthesized toxins on Nav1.7 and Nav1.2 channels are summarized. Copyright © 2012 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   

17.
Effects of a threonine-, tryptophan-, aspartic acid-, lysine-, leucine-, or methionine-free diet fed to rats on the metabolism of nicotinamide were investigated. The body weights of rats and food intakes were greatly decreased by feeding of the diet excluding any of the above essential amino acids compared to the control group, however, not by feeding of an aspartic acid-free diet. The sum of the urinary excretion of nicotinamide, N1-methylnicotinamide (MNA), N1 -methyl-2-pyridone-5-carboxamide (2-Py), and N1 -methyl-4-pyridone-3-carboxamide (4-Py) changed roughly in proportion to food intake. In the groups fed with the threonine- and lysine-free diets, the urinary excretion of MNA greatly increased compared with the control group during the whole experimental period and in the groups fed with the leucine- and methionine-free diets, increased excretion of MNA was observed on day o–day 1. Whenever the increase in MNA excretion was observed, a decrease in 4-Py excretion was observed. This was attributed to the activity of 4-Py-forming MNA oxidase decreasing when rats were fed with the diet excluding one of the essential amino acid except for tryptophan. Therefore, the (2-Py +4-Py)/MNA excretion was greatly decreased by feeding of the diet excluding one of the essential amino acids except for the tryptophan-free diet. These results strengthened our hypothesis that the (2-Py +4-Py)/MNA excretion reflects the adequacy of amino acid nutrition.  相似文献   

18.
This experiment was performed to investigate the possibility that N′ -methylnicotinamide (N′-methyl-3-pyridinecarboxamide) and nicotinamide N-oxide have niacin activity or not in animals. When 20 mg N′-methylnicotinamide per mouse was administered, urinary excretion of nicotinamide, N1-methylnicotinamide (MNA), N1-methyl-2-pyridone-5-carboxamide (2-Py), and N1-methyl-4-pyridone-3-carboxamide (4-Py) increased 24-, 3-, 3-, and 3-fold, respectively, compared with the control values. The increased ratios of MNA, 2-Py, and 4-Py were almost the same as those when 20 mg nicotinamide was administered. Therefore, the relative activity of N′-methylnicotinamide to nicotinamide as niacin was considered to be about 1. When 20 mg nicotinamide N-oxide per mouse was administered, urinary excretion of nicotinamide, MNA, 2-Py, and 4-Py increased 6.4-, 1.8-, 1.6-, and 1.7-fold, respectively, compared with the control values. The increased ratios of MNA, 2-Py, and 4-Py were about 1/2 of those when 20 mg nicotinamide was administered, so the relative activity of nicotinamide N-oxide to nicotinamide as niacin is considered to be about 1/2. In conclusion, it was found the possibility that the reactions N′-methylnicotinamide → nicotinamide and nicotinamide N-oxide → nicotinamide occur, at least in mice, and that therefore N′-methylnicotinamide and nicotinamide N-oxide have niacin activity.  相似文献   

19.
Soon after the emergence of the eighth leaf blades, rice plants were grown with two (1 and 4 mm ) levels of nitrogen (N) supply, and the relationships between the levels of rbcS and rbcL mRNAs, the amount of ribulose 1·5-bisphosphate carboxylase/oxygenase (Rubisco, EC 4.1.1.39) synthesized and the N influx were examined in the eighth leaf blades from emergence through senescence. The levels of both rbcS and rbcL mRNAs, the amount of Rubisco synthesized and the N influx were greater for the 4 mm N treatment than for the 1 mm N treatment throughout the experiment. The amount of Rubisco synthesized was well correlated with the levels of both mRNAs during leaf expansion, but not after the completion of leaf expansion in both N treatments. The ratio of the amount of Rubisco synthesized to the levels of both mRNAs dramatically declined after full expansion. On the other hand, the amount of Rubisco synthesized was well correlated with the N influx in both N treatments. These results indicate that the N influx, namely, N availability, rather than the levels of rbcS and rbcL mRNAs, is more closely related to the amount of Rubisco synthesized in the leaf blade of rice throughout the lifespan of a leaf.  相似文献   

20.
Summary Two carotenoid less mutant strains of Rhodopseudomonas capsulata were isolated. The strain A1a pho- was not able to grow photosynthetically and to synthesize bacteriochlorophyll. However, this organism produced protochlorophyll (phytol ester of Mg-2-vinylpheoporphyrin a5 monomethylester) and protopheophytin. Both pigments were excreted as a macromolecular complex. The intracellular membrane system was poorly developed. A revertant strain of A1a (pho+) was isolated which was able to grow anaerobically in the light as well as aerobically in the dark. The generation time under photosynthetic conditions amounted to 16 hrs whereas under aerobic conditions in the dark that was found to be 2.8 hrs. In addition to bacteriochlorophyll, which was found exclusively in the membrane fraction, protochlorophyll and protopheophytin were synthesized and excreted. A small amount of these pigments was also found intracellulary in the membrane fraction. The structure of the well developed intracytoplasmic membrane reticulum was described.Abbreviations EDTA Ethylenediamine tetraacetic acid-Na - R Rhodospirillum - Rps. Rhodopseudomonas  相似文献   

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