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1.
Although canola is a moderately salt‐tolerant species, its growth, seed yield, and oil production are markedly reduced under salt stress, particularly during the early vegetative growth stage. To identify the mechanisms of salt responsiveness in canola, the proteins expressed in the second and third newly developed leaves of salt‐tolerant, Hyola 308, and salt‐sensitive, Sarigol, cultivars were analyzed. Plants were exposed to 0, 175, and 350 mM NaCl during the vegetative stage. An increase in the Na content and a reduction in growth were observed in the third leaves compared to the second leaves. The accumulation of Na was more pronounced in the salt‐sensitive compared with the salt‐tolerant genotype. Out of 900 protein spots detected on 2‐DE gels, 44 and 31 proteins were differentially expressed in the tolerant and susceptible genotypes, respectively. Cluster analysis based on the expression level of total and responsive proteins indicated that the second leaves had a discriminator role between the two genotypes at both salinity levels. Using MS analysis, 46 proteins could be identified including proteins involved in responses to oxidative stress, energy production, electron transport, translation, and photosynthesis. Our results suggest that these proteins might play roles in canola adaptation to salt stress. 相似文献
2.
Three species of anoxygenic phototrophic heliobacteria, Heliobacterium chlorum, Heliobacterium gestii, and Heliobacillus mobilis, were studied for comparative nitrogen-fixing abilities and regulation of nitrogenase. Significant nitrogenase activity (acetylene reduction) was detected in all species grown photoheterotrophically on N2, although cells of H. mobilis consistently had higher nitrogenase activity than did cells of either H. chlorum or H. gestii. Nitrogen-fixing cultures of all three species of heliobacteria were subject to switch-off of nitrogenase activity by ammonia; glutamine also served to switch-off nitrogenase activity but only in cells of H. mobilis and H. gestii. Placing photosynthetically grown heliobacterial cultures in darkness also served to switch-off nitrogenase activity. Dark-mediated switch-off was complete in lactate-grown heliobacteria but in pyruvate-grown cells substantial rates of nitrogenase activity continued in darkness. In all heliobacteria examined ammonia was assimilated primarily through the glutamine synthetase/glutamate synthase (GS/GOGAT) pathway although significant levels of alanine dehydrogenase were present in extracts of cells of H. gestii, but not in the other species. The results suggest that heliobacteria, like phototrophic purple bacteria, are active N2-fixing bacteria and that despite their gram-positive phylogenetic roots, heliobacteria retain the capacity to control nitrogenase activity by a switch-off type of mechanism. Because of their ability to fix N2 both photosynthetically and in darkness, it is possible that heliobacteria are significant contributors of fixed nitrogen in their paddy soil habitat. 相似文献
3.
It is not known how phosphate (P) deficiency affects the allocation of carbon (C) to biological nitrogen fixation (BNF) in legumes. The alteration of the respiratory and photosynthetic C costs of BNF was investigated under P deficiency. Although BNF can impose considerable sink stimulation on host respiratory and photosynthetic C, it is not known how the change in the C and energy allocation during P deficiency may affect BNF. Nodulated Lupinus luteus plants were grown in sand culture, using a modified Long Ashton nutrient solution containing no nitrogen (N) for ca. four weeks, after which one set was exposed to a P-deficient nutrient medium, while the other set continued growing on a P-sufficient nutrient medium. Phosphorus stress was measured at 20 days after onset of P-starvation. During P stress the decline in nodular P levels was associated with lower BNF and nodule growth. There was also a shift in the balance of photosynthetic and respiratory C toward a loss of C during P stress. Below-ground respiration declined under limiting P conditions. However, during this decline there was also a shift in the proportion of respiratory energy from maintenance toward growth respiration. Under P stress, there was an increased allocation of C toward root growth, thereby decreasing the amount of C available for maintenance respiration. It is therefore possible that the decline in BNF under P deficiency may be due to this change in resource allocation away from respiration associated with direct nutrient uptake, but rather toward a long term nutrient acquisition strategy of increased root growth. 相似文献
4.
Hydrogen metabolism and energy costs of nitrogen fixation 总被引:1,自引:0,他引:1
Abstract The high energy costs of biological nitrogen fixation are partly caused by hydrogen production during the reduction of dinitrogen to ammonia. Some nitrogen-fixing organisms can recycle the evolved hydrogen via a membrane-bound uptake hydrogenase. The energetic aspects of hydrogen metabolism and nitrogen fixation are discussed.
Studies on both isolated nitrogenase proteins and nitrogen-fixing chemostat cultures show that energy limitation will result in a high hydrogen production by nitrogenase. In plant- Rhizobium symbiosis, the supply of oxygen or photosynthetate is the limiting factor for nitrogen fixation. In both cases, nitrogen fixation is energy-limited, and it is concluded that a large amount of hydrogen is produced during nitrogen fixation in these symbioses.
Hydrogen reoxidation yields less energy than the oxidation of endogenous substrates, and therefore expression of hydrogenase under oxygen-limited conditions is energetically unfavourable. Moreover, hydrogen reoxidation can never completely regain the energy invested during hydrogen production. The controversial reports of the effect of hydrogen reoxidation on the efficiency of nitrogen fixation are being discussed.
The determination of the energy costs of nitrogen fixation (expressed as the amount of ATP needed to fix 1 mol of N2 ) using chemostat cultures is described. Calculations show that the nitrogenase-catalysed hydrogen production has more influence on the efficiency of nitrogen fixation than the absence or presence of a hydrogen uptake system. 相似文献
Studies on both isolated nitrogenase proteins and nitrogen-fixing chemostat cultures show that energy limitation will result in a high hydrogen production by nitrogenase. In plant- Rhizobium symbiosis, the supply of oxygen or photosynthetate is the limiting factor for nitrogen fixation. In both cases, nitrogen fixation is energy-limited, and it is concluded that a large amount of hydrogen is produced during nitrogen fixation in these symbioses.
Hydrogen reoxidation yields less energy than the oxidation of endogenous substrates, and therefore expression of hydrogenase under oxygen-limited conditions is energetically unfavourable. Moreover, hydrogen reoxidation can never completely regain the energy invested during hydrogen production. The controversial reports of the effect of hydrogen reoxidation on the efficiency of nitrogen fixation are being discussed.
The determination of the energy costs of nitrogen fixation (expressed as the amount of ATP needed to fix 1 mol of N
5.
Dr. Paul A. Lespinat Yves M. Berlier Guy D. Fauque Rene Toci Gerard Denariaz Jean LeGall 《Journal of industrial microbiology & biotechnology》1987,1(6):383-388
Summary Hydrogenase and nitrogenase activities of sulfate-reducing bacteria allow their adaptation to different nutritional habits even under adverse conditions. These exceptional capabilities of adaptation are important factors in the understanding of their predominant role in problems related to anaerobic metal corrosion. Although the D2–H+ exchange reaction indicated thatDesulfovibrio desulfuricans strain Berre-Sol andDesulfovibrio gigas hydrogenases were reversible, the predominant activity in vivo was hydrogen uptake. Hydrogen production was restricted to some particular conditions such as sulfate or nitrogen starvation. Under diazotrophic conditions, a transient hydrogen evolution was followed by uptake when dinitrogen was effectively fixed. In contrast, hydrogen evolution proceeded when acetylene was substituted as the nitrogenase substrate. Hydrogen can thus serve as an electron donor in sulfate reduction and nitrogen metabolism. 相似文献
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7.
在放线菌结瘤植物(Actinorhizal plants)与放线菌Frankia的共生体系中,固氮酶(N_2ase)活性与所提供的光合产物的量密切相关。通过在同一天的不同对间内,对同株色赤杨光合作用和根瘤中的N_2ase比活、NH_4~ 含量、还原糖含量以及总氮量的变化所做的同步测定结果表明,N_2ase比活的最高峰迟后于光合强度的最高峰;在根瘤内部,NH_4~ 含量和还原糖含量都与N_2ase比活呈负相关,而总氮量则与N_2ase比活呈正相关。本文对这一现象进行了讨论,并且推测还原糖作为光合作用产物的衍生物,直接影响根瘤的固氮作用,它不仅为N.2ase提供固氮所需的能量,而且为固氮产物NH_4~ 提供受体。 相似文献
8.
iTRAQ‐based quantitative proteomic analysis gives insight into sexually different metabolic processes of poplars under nitrogen and phosphorus deficiencies
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Male and female poplars (Populus cathayana Rehd.) respond differently to nitrogen (N) and phosphorus (P) deficiencies. In this study, an iTRAQ‐based quantitative proteomic analysis was performed. N and P deficiencies caused 189 and 144 proteins to change in abundance in males and 244 and 464 in females, respectively. Compared to N‐ and P‐deficient males, both N‐ and P‐deficient females showed a wider range of changes in proteins that are involved in amino acid, carbohydrate and protein metabolism, and the sexual differences were significant. When comparing the effects of N‐ and P‐deficiencies, N‐deficient females expressed more changes in proteins that are involved in stress responses and gene expression regulation, while P‐deficient females showed more changes in proteins that are involved in energy and lipid metabolism, stress responses and gene expression regulation. The quantitative RT‐PCR analysis of stress‐related proteins showed that males have a better expression correlation between mRNA and protein levels than do females. This study shows that P. cathayana females are more sensitive and have more rapid metabolic mechanisms when responding to N and P deficiencies than do males, and P deficiency has a wider range of effects on females than does N deficiency. 相似文献
9.
Nagib Ahsan Yohei Nanjo Hiroko Sawada Yoshihisa Kohno Setsuko Komatsu 《Proteomics》2010,10(14):2605-2619
Considerable soybean yield losses caused by ozone (O3) stress have been demonstrated by large‐scale meta‐analyses of free‐gas concentration enrichment systems. In this study, comparative proteomic approach was employed to explore the differential changes of proteins in O3 target structures such as leaf and chloroplasts of soybean seedlings. Acute O3 exposure (120 parts‐per‐billion) for 3 days did not cause any visible symptoms in developing leaves. However, higher amounts of ROS and lipid peroxidation indicated that severe oxidative burst occurred. Immunoblot analysis of O3‐induced known proteins revealed that proteins were modulated before symptoms became visible. Proteomic analysis identified a total of 20 and 32 differentially expressed proteins from O3‐treated leaf and chloroplast, respectively. Proteins associated with photosynthesis, including photosystem I/II and carbon assimilation decreased following exposure to O3. In contrast, proteins involved in antioxidant defense and carbon metabolism increased. The activity of enzymes involved in carbohydrate metabolism increased following exposure to O3, which is consistent with the decrease in starch and increase in sucrose concentrations. Taken together, these results suggest that carbon allocation is tightly programmed, and starch degradation probably feeds the tricarboxylic acid cycle while the photosynthesis pathway is severely affected during O3 stress. 相似文献
10.
Comparative proteomic analysis reveals similar and distinct features of proteins in dry and wet stigmas 总被引:1,自引:0,他引:1
Angiosperm stigma supports compatible pollen germination and tube growth, resulting in fertilization and seed production. Stigmas are mainly divided into two types, dry and wet, according to the absence or presence of exudates on their surfaces. Here, we used 2DE and MS to identify proteins specifically and preferentially expressed in the stigmas of maize (Zea Mays, dry stigma) and tobacco (Nicotiana tabacum, wet stigma), as well as proteins rinsed from the surface of the tobacco stigma. We found that the specifically and preferentially expressed proteins in maize and tobacco stigmas share similar distributions in functional categories. However, these proteins showed important difference between dry and wet stigmas in a few aspects, such as protein homology in "signal transduction" and "lipid metabolism," relative expression levels of proteins containing signal peptides and proteins in "defense and stress response." These different features might be related to the specific structures and functions of dry and wet stigmas. The possible roles of some stigma-expressed proteins were discussed. Our results provide important information on functions of proteins in dry and wet stigmas and reveal aspects of conservation and divergence between dry and wet stigmas at the proteomic level. 相似文献
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The aims of this work were to investigate the microlocalisation of cadmium (Cd) in Lupinus albus L. cv. Multolupa nodules, and to determine its effects on carbon and nitrogen metabolism. Nodulated white lupin plants were grown in a growth chamber with or without Cd (150 μM). Energy-dispersive X-ray microanalysis showed the walls of the outer nodule cortex cells to be the main area of Cd retention, helping to reduce the harmful effect Cd might have on the amount of N2 fixed by the bacteroids. Sucrose synthase activity declined by 33% in the nodules of the Cd-treated plants, and smaller reductions were recorded in glutamine synthetase, aspartate aminotransferase, alkaline invertase and NADP-dependent isocitrate dehydrogenase activities. The Cd treatment also sharply reduced nodule concentrations of malate, succinate and citrate, while that of starch doubled, but that of sucrose experienced no significant change. In summary, the present results show that white lupins accumulate significant amounts of Cd in their root nodules. However, the activity of some enzymes involved in ammonium assimilation did decline, promoting a reduction in the plant N content. The downregulation of sucrose synthase limits the availability of carbon to the bacteroids, which might interfere with their respiration. Carbon metabolism therefore plays a primary role in the impaired function of the white lupin root nodule caused by Cd, while N metabolism appears to have a more secondary involvement. 相似文献
13.
Comparative proteomic analysis of early salt stress responsive proteins in roots and leaves of rice 总被引:1,自引:0,他引:1
Chih‐Wei Liu Tao‐Shan Chang Yu‐Kai Hsu Arthur Z. Wang Hung‐Chen Yen Yung‐Pei Wu Chang‐Sheng Wang Chien‐Chen Lai 《Proteomics》2014,14(15):1759-1775
Growth and productivity of rice (Oryza sativa L.) are severely affected by salinity. Understanding the mechanisms that protect rice and other important cereal crops from salt stress will help in the development of salt‐stress‐tolerant strains. In this study, rice seedlings of the same genetic species with various salt tolerances were studied. We first used 2DE to resolve the expressed proteome in rice roots and leaves and then used nanospray liquid chromatography/tandem mass spectrometry to identify the differentially expressed proteins in rice seedlings after salt treatment. The 2DE assays revealed that there were 104 differentially expressed protein spots in rice roots and 59 in leaves. Then, we identified 83 proteins in rice roots and 61 proteins in rice leaves by MS analysis. Functional classification analysis revealed that the differentially expressed proteins from roots could be classified into 18 functional categories while those from leaves could be classified into 11 functional categories. The proteins from rice seedlings that most significantly contributed to a protective effect against increased salinity were cysteine synthase, adenosine triphosphate synthase, quercetin 3‐O‐methyltransferase 1, and lipoxygenase 2. Further analysis demonstrated that the primary mechanisms underlying the ability of rice seedlings to tolerate salt stress were glycolysis, purine metabolism, and photosynthesis. Thus, we suggest that differentially expressed proteins may serve as marker group for the salt tolerance of rice. 相似文献
14.
Growth and nitrogen fixation in Lotus japonicus and Medicago truncatula under NaCl stress: nodule carbon metabolism 总被引:1,自引:0,他引:1
López M Herrera-Cervera JA Iribarne C Tejera NA Lluch C 《Journal of plant physiology》2008,165(6):641-650
Lotus japonicus and Medicago truncatula model legumes, which form determined and indeterminate nodules, respectively, provide a convenient system to study plant-Rhizobium interaction and to establish differences between the two types of nodules under salt stress conditions. We examined the effects of 25 and 50mM NaCl doses on growth and nitrogen fixation parameters, as well as carbohydrate content and carbon metabolism of M. truncatula and L. japonicus nodules. The leghemoglobin (Lb) content and nitrogen fixation rate (NFR) were approximately 10.0 and 2.0 times higher, respectively, in nodules of L. japonicus when compared with M. truncatula. Plant growth parameters and nitrogenase activity decreased with NaCl treatments in both legumes. Sucrose was the predominant sugar quantified in nodules of both legumes, showing a decrease in concentration in response to salt stress. The content of trehalose was low (less than 2.5% of total soluble sugars (TSS)) to act as an osmolyte in nodules, despite its concentration being increased under saline conditions. Nodule enzyme activities of trehalose-6-phosphate synthase (TPS) and trehalase (TRE) decreased with salinity. L. japonicus nodule carbon metabolism proved to be less sensitive to salinity than in M. truncatula, as enzymatic activities responsible for the carbon supply to the bacteroids to fuel nitrogen fixation, such as sucrose synthase (SS), alkaline invertase (AI), malate dehydrogenase (MDH) and phosphoenolpyruvate carboxylase (PEPC), were less affected by salt than the corresponding activities in barrel medics. However, nitrogenase activity was only inhibited by salinity in L. japonicus nodules. 相似文献
15.
Trichodesmium is a marine filamentous diazotrophic cyanobacterium and an important contributor of "new" nitrogen in the oligotrophic surface waters of the tropical and sub-tropical oceans. It is unique in that it exclusively fixes N(2) at daytime, although it belongs to the non-heterocystous filamentous segment of the cyanobacterial radiation. Here we present the first quantitative proteomic analysis of Trichodesmium erythraeum IMS101 when grown under different nitrogen regimes using 2-DE/MALDI-TOF-MS. Addition of combined nitrogen (NO3-) prevented development of the morphological characteristics of the N(2)-fixing cell type (diazocytes), inhibited expression of the nitrogenase enzyme subunits and consequently N(2) fixation activity. The diazotrophic regime (N(2) versus NO3- cultures) elicited the differential expression of more than 100 proteins, which represented 13.5% of the separated proteins. Besides proteins directly related to N(2) fixation, proteins involved in the synthesis of reducing equivalents and the generation of a micro-oxic environment were strongly up-regulated, as was in particular Dps, a protein related to iron acquisition and potentially other vital cellular processes. In contrast, proteins involved in the S-adenosylmethionine (SAM) cycle, synthesis of amino acids and production of carbon skeletons for storage and synthesis of amino acids were suppressed. The data are discussed in the context of Trichodesmium's unusual N(2)-fixing physiology. 相似文献
16.
放牧对牧草光合作用、呼吸作用和氮、碳吸收与转运的影响 总被引:9,自引:1,他引:8
研究放牧对草地植物生理活动的影响,对于揭示草地放牧演替的生理机制有重要意义.大量研究表明,家畜放牧对牧草光合作用、呼吸作用以及C和N吸收与转运的影响,可以分为生理伤害和生理恢复2个阶段.放牧通过改变草地冠层结构影响牧草光合作用,净光合作用速率短期内迅速下降,随着叶面积指数增加又逐渐上升,呼吸作用有相似的变化趋势.牧草放牧后再生长所需的C和N最初主要来自根系和留茬中的贮藏物质,此后随着牧草生长恢复逐渐由同化作用供给,C代谢与土壤N水平负相关.放牧后牧草生理活动变化与牧草遗传特性、种间竞争、家畜放牧特征、非生物环境等因素密切相关. 相似文献
17.
Isotope analysis of the biochemical fractions isolated quantitatively from young and mature leaves of Bryophyllum daigremontianum Berger have been carried out before and after a dark period of accumulation of organic acids. The mature leaf is enriched in 13C compared to the young leaf. The 13C values of the different leaf constituents vary between the 13C values of C4 plants (-11) and those of C3 plants (-27). During the dark period, the two types of leaves store organic acids with 13C values of -15 and lose insoluble sugars, including starch with a 13C value of -12. Furthermore, young leaves store phosphorylated compounds with 13C values of -11 and lose weakly polymerised sugars with 13C values of -18. These results led to the formulation of a hypothesis of the origin of the two substrates of -carboxylation: phosphoenolpyruvate arises from the glycolytic breakdown of the insoluble sugars rich in 13C, and the major portion of the CO2 is the result of the complete breakdown (respiration) of the soluble sugars rich in 12C. The existence of two independent sugar pools leads to the assumption that there are two separate glycolytic pathways. The 13C enrichment of the stored products of the young leaves in the day seems to be the result of a weak discrimination for 13C by ribulose diphosphate carboxylase, which reassimilates to a great extent the CO2 released from malate accumulated in the night.Abbreviations CAM
crassulacean acid metabolism
- C3 metabolism
metabolism with primary carbon fixed by the Calvin and Benson pathway
- C4 metabolism
metabolism with primary carbon fixed by the Hatch and Slack pathway
- 13C()
(Rsample-RPDB) 103/RPDB where PDB=Pee Dee belemnite (belemite from the Pee Dee formation South Carolina) and R=13C/12C
- NAD-MDH(EC1.1.1.37)
NAD-malate dehydrogenase
- NADP-ME (EC1.1.1.40)
NADP-malic enzyme
- PEP
phosphoenolpyruvate
- PEPC (EC4.1.1.31)
PEP carboxylase
- PGA
phosphoglyceric acid
- Py.di-PK(EC2.7.9.1)
pyruvate, Pi-dikinase
- RuDP
ribulose diphosphate
- RuDPC (EC4.1.1.39)
RuDP carboxylase 相似文献
18.
Simon V. Avery Marvin E. Miller Geoffrey M. Gadd Geoffrey A. Codd Joseph J. Cooney 《FEMS microbiology letters》1991,84(2):205-210
Abstract Inhibition of photosynthesis by a range of organotin compounds in Plectonema boryanum was concentration-dependent and decreased in the order tributyltin (Bu3 SnCl) > tripropyltin (Pr3 SnCl) ≥ dibutyltin (Bu2 SnCl2 ) ≥ triphenyltin (Ph3 SnCl) > triethyltin (Et3 SnCl) > trimethyltin (Me3 SnCl) > monobutyltin (BuSnCl3 ). IC50 values were determined for the most toxic organotin species and varied from approximately 1.2 μM for Bu3 SnCl to approximately 13 μM for Ph3 SnCl. A similar order of inhibition of photosynthesis was observed in Anabaena cylindrica , although here IC50 values were slightly lower (e.g. approximately 1 μM for Bu3 SnCl and 5 μM for Ph3 SnCl).Nitrogenase activity was generally more sensitive to inhibition by organotin compounds than photosynthesis in A. cylindrica and this was particularlyy evident for Bu2 SnCl2 ; approximate IC50 values for Bu2 SnCl2 were 3 and 9 μM, as estimated by nitrogenase activity and photosynthesis, respectively. These results indicate that organotin compounds have the potential to inhibit cyanobacterial metabolism in aquatic systems. 相似文献
19.
Summary Soybeans (Glycine max (L.) Merr.) have a high N requirement which is fulfilled by soil N uptake and N2-fixation. This study was concerned with the effects of past yield selection on N2-fixation in soybeans.The soybean cultivars, Lincoln, Shelby, and Williams, which represent successive improvements in the Lincoln germplasm, and a non-nodulating control were planted in a soil containing15N labelled organic matter. Two replications occurred on soil previously cropped to alfalfa and two on soil previously cropped to soybeans. Plants were harvested at five growth stages and leaf area, plant weight, total N, and atom percent15N were determined. Mature grain was harvested and yield components were also determined, as well as the total N and15N content.Cultivar differences in total dry matter were only evident at physiological maturity, when Williams contained the greatest dry matter. Williams exhibited the longest period of seed formation and seed fill and also had the highest grain yield which resulted from a larger weight per seed.The N content of the cultivars did not vary until physiological maturity when Williams contained the highest percent N. The quantity of N fixed at physiological maturity was highest for Williams and lowest for Lincoln. Fixed N contained in the harvested grain was greater for Williams than for the other two cultivars. The fraction of the total plant N derived from fixation was not greatly affected by cultivar and all cultivars acquired an average of 50% of their total N through N2-fixation.Previous cropping history greatly affected the quantity of N fixed and the fraction of the total plant N derived from fixation. Soybeans following soybeans were more dependent upon N2-fixation than soybeans following alfalfa with the former deriving 65% of the total plant N from fixation and the latter only 32%. These soybean cultivars apparently utilized soil N first and then used N2-fixation to satisfy their N requirement.The past selection for higher yield has resulted in soybean cultivars with improved capacities to fix atmospheric N2 and an improved ability to take up available soil N. 相似文献
20.
Michael P. Lesser 《Hydrobiologia》2008,598(1):1-9
The biological effects of ultraviolet radiation (UVR; 290–400 nm), especially the UV-B (320–400 nm) component of the spectrum,
include both direct and indirect effects on many cellular processes. In cyanobacteria both photosynthesis and nitrogen fixation
can be affected directly by UVR, and indirectly by UVR through the production of reactive oxygen species (ROS). For the heterocystous
cyanobacterium, Anabaena sp. (Newton’s strain), exposure to UVR causes a significant decline in the quantum yields of photosystem II (PSII) fluorescence
and maximum productivity despite an increase in UVR absorbing compounds, mycosporine-like amino acids (MAAs), in those cells
exposed to UVR. Concurrent with these observations are significant increases in the activities of superoxide dismutase indicative
of an increase in the level of oxidative stress in cells exposed to UVR. Additionally, measurements of nitrogenase activity
(acetylene reduction) show a significant decrease in cyanobacteria exposed to UVR, which manifests itself as a decrease in
cellular nitrogen and an increase in C:N ratios. These results show that these nitrogen-fixing cyanobacteria are particularly
sensitive to UVR, both its direct and indirect effects. The effects of UVR reported here add to the increasing evidence that
UVR effects on this important group of prokaryotes could affect the input of new nitrogen, and the biogeochemical cycling
of this essential macronutrient in terrestrial, marine, and freshwater habitats.
Handling editor: L. Naselli-Flores
An erratum to this article can be found at 相似文献