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1.
Previous studies have demonstrated that when cells of Chlorellaprotothecoides are incubated in a medium containing glucosebut no nitrogen source, they are profoundly bleached with degenerationof chloroplast structure and photosynthetic activity. When anitrogen source (urea) is added to the glucose medium, bleachingof algal cells is greatly suppressed. In this work the metabolismof glucose in the process of glucose-induced bleaching was studiedusing 14C-glucose as tracer. Changes in algal cell activityfor 14CO2-evolution and 14C-incorporation into various cellularsubstances from 14C-glucose were followed. Most conspicuouswere increases in cellular activities for assimilating 14C-glucoseinto lipids (fatty acids) and glucose polymer. When urea wasadded to the glucose medium, the incorporation of 14C by algalcells into fatty acids was greatly reduced, while the assimilationof 14C into glucose polymer was increased. These and previous observations suggest that the formation oflarge amounts of lipids (fatty acids) probably is causally relatedto the induction of algal cell bleaching. (Received March 5, 1969; ) 相似文献
2.
The process of bleaching of Chlorella protothecoides inducedby the addition of glucose was strongly inhibited by cycloheximide,an inhibitor of protein synthesis, whereas it was suppressedonly weakly by chloramphenicol, puromycin and ethionine. Whencycloheximide was added simultaneously with glucose at the beginningof die bleaching experiment, no bleaching of algal cells occurredduring the subsequent incubation. When it was added after glucose,the bleaching of algal cells proceeded for a period of timeas actively as in the control, then gradually ceased. Cycloheximidewas found to suppress the uptake of glucose by algal cells,and to severely inhibit the assimilation of glucose into lipidswhen added at the beginning of the bleaching experiment. Theseinhibitory effects of cycloheximide are discussed in relationto the induction of "glucose-bleaching" in algal cells. (Received December 16, 1968; ) 相似文献
3.
Changes in photosynthetic carbon metabolism during the glucosebleaching of Chlorella protothecoides cells were investigatedusing NaH14CO3 as tracer. Several hours after incubating thegreen algal cells in the glucose medium in the dark, the ratesof 14C-incorporation into glucose polymers and sucrose decreasedand the incorporation into the lipid fraction (fatty acids)greatly increased. At this stage, the rate of photosynthetic14CO2 fixation and the chlorophyll content were practicallythe same as in the starting green cells. Afterwards, the photosyntheticcapacity and chlorophyll content continued to decrease throughoutthe experimental period. In contrast, when photosynthetic 14CO2fixation of green cells was carried out in the medium containingglucose, the rate of 14C-incorporation into glucose polymersincreased, though there was no change in the incorporationsinto sucrose and the lipid fraction.
1Part of this investigation was reported at the Conference "ComparativeBiochemistry and Biophysics of Photosynthesis" (Japan-U.S. CooperativeScience Program) held at Hakone, Japan in 1967.
2Present address: Faculty of Agriculture, Tamagawa University,Machida-shi, Tokyo, Japan. (Received June 10, 1974; ) 相似文献
4.
- As previously demonstrated, normal cells of Chlorella protothecoidesare bleached with degeneration of chloroplasts when they areincubated, under aerobic conditionseither in the lightor in darkness, in a glucose-containing medium withoutadded nitrogen source ("glucose-bleaching"). It was found inthe present study that under the atmosphere of N2, neither bleachingnor growth of algal cells occurs in the dark, while in the lighta significant growth of cells takes place with formation ofa certain amount of chlorophyll.
- Studies on the effects ofvarious inhibitors (ammonium ion,DNP, CMU, -hydroxysulphonates,arsenate, cyanide, azide, andantimycin A) under different conditionsshowed that oxidativephosphorylation is a necessary processfor the occurrence ofthe glucosebleaching as well as the assimilationof glucose(cellular growth). Under light-anaerobic conditionsin the presenceof glucose, assimilation of glucose (cellulargrowth) takesplace being supported by photophosphorylation,but no bleachingoccurs.
- When the algal cells in the courseof bleaching were transferredto the glucose-free mineral medium,the cell growth ceased immediatelybut the cell bleaching proceededfor several hours before itscessation. The respiratory activity,which was high in the glucose-containingmedium, became loweron transferring the algal cells into theglucose-free medium.The lowered level of respiration was maintained,for more than8 hr after the transfer of cells to the glucose-freemedium.
- When the cells in the course of bleaching were placed underthe atmosphere of N2, the cell bleaching ceased almost instantaneously.
- Based on these observations and other inhibition experiments,it was inferred that a certain intermediate(s) produced by theaerobic respiration of glucose is closely associated with theoccurrence of cell bleaching, and that an O2-requiring stepmay be involved in the process of chlorophyll degradation.
5.
- Based on the microscopic observations, two stages, "giant cellstage" and the subsequent "palmelloid body stage", were distinguishedin the process of formation of giant Chlorella induced by theaddition of sugars. The "giant cell" is much larger in sizethan the control cell, but the other morphological featuresare the same as those of the latter. The "palmelloid body" isa form composed of many conjoined autospores.
- When a highconcentration of glucose was maintained in the medium,gigantismwas also maintained. Under this condition, the algashows acyclic transformation between "giant cell" and "palmelloidbody"without returning to the small single cells.
- Large amountsof carbohydrate composed of hexose were foundto be accumulatedin the giant algal cells, and it was inferredthat this carbohydrateaccumulation causes greater enlargementof cell volume as comparedwith control cells.
- Uronic acids, which were found to be absentin the control cells,were formed and lost in the cells culturedin the glucose mediumin parallel with the appearance and disappearanceof gigantism.
- Pectic substances, from which uronic acids areconsidered tobe derived during the extraction procedure, werefound to bepresent only in giant Chlorella.
- The conjoinedautospores in giant Chlorella (at the palmelloidbody stage)were separated to some extent by the addition ofEDTA, and theresulting cells were similar to control Chlorellacells.
- Basedon these results it was inferred that inductive formationofthe pectic substances is causally related with the appearanceof "palmelloid body".
6.
WhenChlorella pyrenoidosa photoassimilates 3H-14C-acetate theglycollic acid formed shows a high 3H/14C ratio, the only othercompounds showing similar ratios being glycerate and serine.The 3H/14C ratio of glycollate was unaffected by the TCA cycleinhibitors MFA, diethylmalonate and arsenite showing that 3Hin glycollate does not result from the oxidation of acetatevia the TCA cycle, the resulting NADP3H2 or NAD3H2 being usedfor the reduction of the glycollate precursor. Although DCMUdecreased the 3H/14C ratio, complete inhibition of glycollatelabelling was not observed with 106 M DCMU, at whichconcentration complete inhibition of the Hill reaction is achieved.Although the 3H/14C ratio was unaltered, total dpm of both 14Cand 3H in glycollate were increased by INH. The 3H/14C ratiosof glycerate and serine were decreased by INH, as were the totaldpm of 3H and 14C incorporated into these compounds. Thus, INHinhibits the further metabolism of glycollate to glycerate andserine. The effect of INH on incorporation of 14C-I-acetateinto various cell fractions was investigated. The incorporationof 14C into polysaccharide and lipid was decreased, while theincorporation of 14C into the water-soluble fraction of cellsand therelease of 14CO2 were little affected. Although glycollicacid was an early product of acetate photoassimilation in Chlorellapyrenoidosa, glycollate excretion does not take place undera wide range of environmental conditions shown to favour glycollateexcretion by other algae. However, small amounts of labelledglycollate were detected in the supernatant from the cells duringthe photoassimilation of 3H-14C-acetate, but this glycollatedid not show the high 3H/14C ratio of glycollate present withinthe cell. The failure of Chlorella pyrenoidosa to excrete appreciableamounts of glycollate when photoassimilating acetate or carbondioxide was considered to result from the presence of glycollateoxidase (EC 1.1.3.1
[EC]
) which allowed the further metabolism ofglycollate. Besides glycollate oxidase, glyoxylate reductasewas also demonstrated in Chlorella pyrenoidosa so that glycollatecould function in hydrogen transfer during the photoassimilationof acetate. 相似文献
7.
By growing Chlorella protothecoides under certain nutritionaland light conditions the following three different types ofalgal cells were obtained: (i) normal "green" cells grown ina medium rich in a nitrogen source (urea) and poor in glucoseunder illumination, (ii) "etiolated" cells cultivated in thesame medium in darkness, and (iii) "glucose-bleached" cellsgrown, in the light or in darkness, in a medium rich in glucoseand poor in the nitrogen source. The "glucose-bleached" cellscontain profoundly degenerated plastids, and the "etiolated"cells have only partially organized plastids. From these algalcells RNA was extracted by the cold phenol method, and fractionatedby MAK column chromatography and sucrose density gradient centrifugation,making use of 32P-labelled E. coli RNA as the internal marker.It was found that in comparison with the green cells that arerich in chloroplast ribosomal RNA as well as in nonchloroplastic("cytoplasmic") ribosomal RNA, the etiolated cells possess acomparable amount of "cytoplasmic" rRNA but a significantlylesser amount of chloroplast rRNA. Both types of rRNA existat extremely low levels in the glucose-bleached cells. During the process of bleaching (chloroplast degeneration) ofthe green cells induced by the addition of a high concentrationof glucose, marked changes were observed in the patterns offractionation of RNA as followed by the above procedures. Itwas disclosed that the chloroplast rRNA is rapidly degradedduring an early phase of the bleaching process, while the quantityof "cytoplasmic" rRNA remained almost unaltered.
1Part of this work was reported at the Symposium on Cell Differentiationsponsored by the Institute of Applied Microbiology, Universityof Tokyo, in November 1965, and at the Symposium on Biogenesisof Subcellular Particles, the 7th Internatl. Congress of Biochemistry,Tokyo, 1967.
2Present address: Faculty of Pharmaceutical Sciences, Universityof Hokkaido, Sapporo. 相似文献
8.
Chlorella pyrenoidosa can utilize sodium acetate as a carbonsource for growth in the light. Growth proceeds under aerobicconditions both in the presence and in the absence of carbondioxide, but under anaerobic conditions only in its presence.The assimilation of acetate does not result from oxidation tocarbon dioxide followed by photosynthetic fixation because theproducts of 14C-acetate assimilation are different from theproducts of 14CO2 fixation in the presence of unlabelled acetate. In aerobic conditions 10-6 M DCMU induces a pattern of acetateassimilation in the light similar to that in the dark. Thus,in the presence of DCMU in the light, less acetate carbon isincorporated into cells, particularly into lipids, polysaccharide,and protein, and more is released as carbon dioxide than inits absence. The effect of 4 x 10-3 M MFA on acetate assimilationin the presence of 10-6 M DCMU is the same in light and dark.Acetate assimilation is unaffected by desaspidine and sodiumbisulphite. The mean generation time of C. pyrenoidosa growing on acetatein the light under aerobic conditions is 20 hours. When 10-5M DCMU is added the mean generation time is 60 hours, the sameas that for Chlorella growing on acetate in the dark. The activityof the enzymes of the glyoxylate cycle, isocitrate lyase (E.C.4.1.3.1.)and malate synthetase (E.C.4.1.3.2.) is repressed in the light,but activity of both enzymes increases markedly when DCMU isadded. 相似文献
9.
- It has been demonstrated that when the cells of Chlorella protothecoidesare grown mixotrophically under illumination in a medium richin nitrogen source (urea) and poor in glucose, the normal greencells are obtained, while in a medium rich in glucose and poorin the nitrogen source, entirely chlorophyll-less cells withprofoundly degenerated plastids ("glucose-bleached" cells) areproduced, irrespective of whether in the light or in darkness.The "glucose-bleached" cells turn green with regeneration offully organized chloroplasts when incubated in a nitrogen-enrichedmedium in the light ("light-greening"), while in the dark theybecome pale green with formation of only partially organizedchloroplasts ("dark-greening"). When, on the other hand, thegreen cells are transferred into a medium enriched with glucose,they are bleached fairly rapidly with degeneration of chloro-plastsin the light as well as in darkness ("bleaching"). Using 35Sas a tracer, investigations were made on the changes of contentsof the algal cells in sulfolipid and other sulfur compoundsduring the processes of the greening and bleaching.
- By determiningthe radioactivities of chromatographically separatedsulfur-containingcompounds of the uniformly 35S-labeled green("G") and "glucose-bleached"("W") cells, it was found thatthe concentration of a speciesof sulfolipid (discovered byBENSON et al.) as well as thoseof glutathione, sulfotriosesand most of the other sulfur-containingcompounds were at least5 times higher in the "G" cells thanin the "W" cells, whilesulfoquinovosyl glycerol was presentin approximately equalamounts in the two types of cells.
- Phospholipidcontents and compositions in the two types of algalcells werefound to be practically identical.
- The sulfolipid contentof algal cells increased and decreasedalmost in parallel withthe processes of greening and bleaching,respectively.
- Studyingthe mode of incorporation of radiosulfate into varioussulfurcompounds of algal cells during the processes of "light-anddark-greening" and "bleaching" (lasting about 70 hr), itwasfound that active 35S-incorporation into sulfolipid occurredthroughout the process of "light-greening," while in the "dark-greening"and "bleaching" the active incorporation abruptly ceased afterthe initial 24 hr period of experiments. It was suggested thatthe biosynthesis of the sulfolipid is closely related to theformation of photosynthetic apparatus in chloroplast.
- Whenthe 35S-labeled green cells were bleached in a medium containingno radiosulfate, the 35S-sulfolipid and most of other 35S-sulfurcompounds decreased markedly but the 35S-sulfoquinovosyl glycerolincreased considerably. It was inferred that the deacylationof the sulfolipid, a surfactant lipid, with formation of watersoluble sulfoquinovosyl glycerol may be a cardinal event ofbleaching process, causing a disintegration of the intact architechtureof photosynthetic apparatus.
- Based on these observations itwas concluded that the sulfolipidis an integral component ofphotosynthetic structure.
10.
Plastids were isolated from the developing endosperm of Ricinuscommunis L. and purified by rate-zonal centrifugation on discontinuoussucrose gradients. Assay conditions were optimized for the uptakeand incorporation of 14C-acetate into lipids by intact plastids.Using the optimized conditions, the uptake and incorporationof several 14C-glycolytic intermediates into lipids were examined.Neither sucrose nor glucose-6-phosphate was incorporated intolipids. In order of increasing magnitude of incorporation, glucose,fructose, 3-phosphoglycerate, acetate, and pyruvate were metabolizedto chloroform-methanol (2: 1 v/v) soluble products. Pyridoxal-5'-phosphateinhibited the incorporation of 3-phosphoglycerate into lipidswhereas -cyano-4 hydroxycinnamate was without effect on pyruvateincorporation. Avidin and cerulenin did not inhibit the incorporationof acetate into lipids by intact plastids. Key words: Ricinus communis, Plastids, Lipid synthesis, Glycolytic intermediates 相似文献
11.
The feeding behaviour of two freshwater zooplankton species,the calanoid copepod Eudiaptomus gracilis and the cladoceranDaphnia longispina, at extremely low food concentrations hasbeen studied in order to test whether the animals react as predictedby the models of optimal foraging. Three different sized algae were offered in concentrations downto 1µg C/litre at 7°C during winter and 19°C duringsummer. Ingestion rates were measured by use of a flow-through14C-technique In contrast to the findings of several authors working withmarine copepods a threshold concentration where the animalsceased filtering could be detected only in one experiment byregression analysis (Daphnia, 19°C, food: Stichococcus).A depression of the filtering rate at low concentrations wasobserved only in Daphnia at 19°C with Stichococcus and Scenedesmusas food. It is supposed that in this case the reduction of thefiltering rate is not a direct response of the filtrator, butis caused by exhaustion due to the experimental conditions. As freshwater zooplankton is very rarely exposed to food abundancesas low as in the marine environment, there seems to be no selectionpressure favouring the evolution of an "optimal forager" behaviour.
(1)Supported by Deutsche Forschungsgemeinschaft 相似文献
12.
- Investigations were made on the modes of synthesis of differentspecies of RNA which appear during the greening (chloroplastregeneration) of the "glucose-bleached" cells of Chlorella protothecoidescontaining profoundly degenerated plastids.
- RNAs were extractedfrom the algal cells which had been labelledwith 32P for 1hr before harvesting at different stages of thegreening inthe light and in darkness, and subjected to columnchromatographywith methylated albumin-coated kieselguhr. Itwas found that,during the greening process, the elution profilesof RNAs, interms of the optical density at 260 mµ and32P-radioactivity,changed profoundly.
- Based on these and other results, it wasconcluded that duringan early phase of the chloroplast regenerationin the glucosebleachedalgal cells, there occurs an active formationof both ribosomalRNAs (rRNAs) and the RNAs corresponding tosoluble RNA (sRNA),the formation coming, however, later toa standstill when thesynthesis of chlorophyll has proceededto a certain level. Thequantity ratio of sRNA to rRNA was foundto be constant (30:70)at different stages of the greening (bothin the light and indarkness), with a few exceptions. The synthesisof the chloroplastribosomal RNA is markedly accelerated bylight, and its maximumrate is observed sometime later thanthat of the non-chloroplast("cytoplasmic") ribosomal RNA. Itwas suggested that there areat least two different sites ofsynthesis of ribosomal RNAs,one in the plastid and the otheroutside of it (most probablyin the nucleus).
13.
Using synchronized cells of Chlorella pyrenoidosa, the incorporationpatterns of 14C into various metabolites with and without nitrogensources were studied under steady-state and non steady-stateconditions. From the patterns it was found that the smallestcells which are divided in the dark utilize nitrate and nitritevery little, if at all. The importance of ammonia for regulation of secondary flow forChlorella is discussed and the suggested regulatory points aredescribed.
1This work was sponsored, in part, by the U.S. Atomic EnergyCommission (Received January 26, 1970; ) 相似文献
14.
Carbon dioxide enhanced chloroplast regeneration in glucose-bleachedcells of Chlorella protothecoides in the presence of CMU inthe light. Both the formation of chlorophyll and the synthesesof RNA and protein were considerably enhanced. The CO2 metabolism of algal cells during greening was investigatedusing 14C-bicarbonate as the tracer. Radiocarbon was largelyincorporated into purine and pyrimidine bases in nucleic acidand the arginine in protein, specifically at the crabon atomsderived from carbamylphosphate.
1Part of this investigation was reported at the conference onthe "Autonomy and biogenesis of mitochondria and chloroplasts"held at Canberra in 1969 (4). (Received August 19, 1975; ) 相似文献
15.
Regulation of sterol synthesis was studied in Solanum species.A significant negative correlation was found between sterolcontent and rate of sterol synthesis from (1-14C) acetate inplant organs of Solanum nigrum and cell cultures of S. dulcamara.Exogenous cholesterol significantly inhibited the rate of sterolsynthesis from (14C) acetate in cell cultures of S. dulcamarawithout affecting synthesis from (3H) mevalonate. Exogenouscholesterol stimulated the rate of total lipid synthesis fromboth (14C) acetate and (3H) mevalonate. Thus, cholesterol inhibitedconversion of acetate to mevalonate; this is taken as evidenceof a negative feedback control on sterol synthesis. Key words: Feedback control, Phytosterol biosynthesis, Plant cell culture, Solanum species 相似文献
16.
Argyroudi-Akoyunoglou J. H.; Kondylaki S.; Akoyunoglou G. 《Plant & cell physiology》1976,17(5):939-954
The plastids of young dark-grown bean leaves, exposed to periodiclight are agranal, devoid of chlorophyll b and contain primarythylakoids and chlorophyll a. Transfer of these plants to continuousillumination results in synthesis of new chlorophyll a, chlorophyllb and grana. This study was done in order to study whether andhow the grana are formed from preexisting primary thylakoids.14C--aminolevulinic acid was used to label the chlorophyll aof the primary thylakoids, and its fate was studied after transferof the plants to continuous light. It was found that chlorophyll b and grana become 14C-labelled.The total radioactivity of chlorophyll b per bean increasedwith the parallel decrease of that of chlorophyll a. All subchloroplastfractions, obtained after digitonin disruption of chloroplasts,contained chlorophyll a of equal specific radioactivity. Thespecific radioactivity of chlorophyll b was lower than thatof chlorophyll a, and, in addition, it was lower in the granathan in the stroma lamellae fraction. The data suggest that chlorophyll b is formed from chlorophylla; the grana are formed by stacking of preexisting primary thylakoids;chlorophyll b is synthesized faster in the grana than the stromalamellae; the newly formed chlorophyll a molecules are distributedat random throughout the developing photosynthetic membraneand not on specific growing sites. (Received April 24, 1976; ) 相似文献
17.
The carbon metabolism in cell walls of Chlorella ellipsoideawas studied by following 14C incorporation into cell wall constituentsin photosynthesizing, synchronously growing cells. The rateof incorporation was higher at an early growth phase of thecell cycle. The 14C was incorporated into both the major cellwall constituents, hemicellulose and rigid wall,and the radioactivity in the latter was distributed into itstwo components, glucosamine and amino acids. In pulse-chaseexperiments, the 14C fixed photosynthetically in the precedingcell cycle was rapidly transferred into the cell wall constituentsat the early growth phase of the ongoing cell cycle, and thereafterwas gradually released from the cell walls, although the totalamount of 14C in the cells remained constant. It was concludedthat the cell wall constituents are turned over during the growthphase of the algal cell cycle, and that the cell wall metabolismin the ongoing cell cycle is closely connected with the carbonmetabolism in the preceding cell cycle. (Received February 3, 1982; Accepted June 21, 1982) 相似文献
18.
The biomass and metabolic activity of bacterioplankton weremeasured over 1 year in the Ems Dollard Estuary, a part of theDutch-German Wadden Sea. Very productive phyzoplankton blooms,composed mainly of diatoms and the haptophycean alga Phaeocystispouchetii, are a feature of the estuarine section studied. Theproduction of bacterial populations, as measured using the [3H]thymidinemethod broadly followed the phytoplankton density during bloomsin spring and late summer. There was no indication of a disproportionateincrease in bacterial production during the bloom or declineof particular algal species. The rate at which 14C-labelledglucose, glutamate and leucine were incorporated by bacterialpopulations, measured as a metabolic potential, varied seasonally,but did not precisely follow the rate of [3H]thymidine incorporation.The utilization of the absorbed 14C substrates for respirationor for cellular synthesis was constant over a prolonged periodof bacterial growth; apparent yields of 0.7, 0.4 and 0.8 weremeasured for glucose, glutamate and leucine, respectively. Inthe colder season most of the absorbed substrate was respired.The production by pelagic bacteria was 60 gC m2 y1,a value that amounted to 12% of the pelagic primary production.A preliminary experiment with a mixed culture of the abundantlyoccurring diatom species Thalassiosira excentrica and a marinespirillum, indicated that part of the algal exudates were rapidlyconverted by the bacteria, but another part resisted degradation.The incomplete bacterial degradation of algal exudates togetherwith the short residence time of the estuarine phytoplanktonmay contribute to the apparently incomplete mineralisation ofthe primary production in the water. 相似文献
19.
A new imageanalysis-based technique was used to quantitatively examine the effectsof the "Ca2+-jump"activation protocol on the maintenance of fiber quality in skinnedrabbit psoas muscle fiber segments. Specifically, contractions in pCa4.6 were preceded by short-duration "preactivation" soaks in asolution in which EGTA was replaced with thelow-Ca2+ buffering capacity analoghexamethylenediamine-N, N, N', N'-tetraacetate, which facilitated rapid Ca2+equilibration within the fiber segments. Fiber quality was assessed byexamining the Fourier spectra of the muscle fiber images before, during, and after activation. Segment lengths were typically below 500 µm, thus allowing the majority of the sarcomeres to be visualized inthe field of view (×200 and ×400 magnification). Thepreactivation protocol resulted in less deterioration of fiber qualitywith repetitive activation. In addition, there was also a significant reduction in the time required to reach the 50% level of maximum tension, with no significant change in the maximum tension level. 相似文献
20.
The kinetics of 14C-2-acetate assimilation by Chlorella pyrenoidosain the light were examined. Under aerobic conditions the primaryproduct of acetate assimilation was succinic acid which, afterten seconds, contained over 60 per cent of the 14C incorporatedby the cells. The percentage of the total 14C in succinate fellwith time, while that in citrate and glutamate increased. After1800 sec over 60 per cent of 14C was present in two compounds,glutamic acid and an unknown compound (X). Glucose-6-phosphate,fructose-6-phosphate, phosphoglyceric acid and phosphoenolpyruvicacid became labelled after 60 sec but together never containedmore than one per cent of the total 14C incorporated. Underanaerobic conditions succinate was still the primary productof acetate assimilation, and the absence of carbon dioxide resultedin a decrease in 14C incorporation into compound X. The patternof acetate assimilation in acetate grown and acetate adaptedChlorella was very similar to that in photo-autotrophicallygrown Chlorella. In the presence of 106M DCMU, succinicacid was the primary product of acetate assimilation, but therewas an early Incorporation of 14C into glutamate, aspartate,and malate. 4 x103M MFA did not effect the early incorporationof 14C into succinic acid, but resulted in accumulation of 14Cin citrate and a decreased amount in glutamate and in compound X. 相似文献