The Experts below are selected from a list of 91098 Experts worldwide ranked by ideXlab platform
Joseph J Kieber - One of the best experts on this subject based on the ideXlab platform.
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1-Aminocyclopropane-1-Carboxylic Acid as a signalling molecule in plants
AoB Plants, 2013Co-Authors: G. M. Yoon, Joseph J KieberAbstract:Ethylene influences many aspects of plant growth and development including germination, leaf and floral senescence and abscission, fruit ripening, and the response to abiotic and biotic stress. The pathways involved in the biosynthesis of and response to ethylene have been elucidated. The first committed and generally rate-limiting step in ethylene biosynthesis is the conversion of S-adenosyl-methionine to 1-Aminocyclopropane-1-Carboxylic Acid (ACC) by ACC synthase (ACS). This enzyme is encoded by a gene family in most plants and is subject to both transcriptional and post-transcriptional control in response to numerous endogenous and environmental cues. In addition to its well-described function as the immediate precursor of ethylene, recent studies suggest an alternative, non-canonical role for ACC. These studies found that in some contexts, chemical inhibitors of ethylene biosynthesis caused effects on root cell expansion that were not observed when ethylene perception or signalling was disrupted, suggesting that ACC, but not ethylene, played a role in these specific processes. Furthermore, mutation of all eight ACS genes in Arabidopsis was found to result in embryo lethality, in contrast to the relatively modest developmental effects of null mutants in the ethylene signalling components. This divergence suggests that ACC may play a role as a signalling molecule in plants. Here, we first review the ethylene biosynthesis pathway and then discuss these studies suggesting an independent role of ACC as a signalling molecule.
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Two Arabidopsis mutants that overproduce ethylene are affected in the posttranscriptional regulation of 1-Aminocyclopropane-1-Carboxylic Acid synthase.
Plant physiology, 1999Co-Authors: K E Woeste, C. Ye, Joseph J KieberAbstract:The Arabidopsis mutants eto1 (ethylene overproducer) and eto3 produce elevated levels of ethylene as etiolated seedlings. Ethylene production in these seedlings peaks at 60 to 96 h, and then declines back to almost wild-type levels. Ethylene overproduction in eto1 and eto3 is limited mainly to etiolated seedlings; light-grown seedlings and various adult tissues produce close to wild-type amounts of ethylene. Several compounds that induce ethylene biosynthesis in wild-type, etiolated seedlings through distinct 1-Aminocyclopropane-1-Carboxylic Acid (ACC) synthase (ACS) isoforms were found to act synergistically with eto1 and eto3, as did the ethylene-insensitive mutation etr1 (ethylene resistant), which blocks feedback inhibition of biosynthesis. ACS activity, the rate-limiting step of ethylene biosynthesis, was highly elevated in both eto1 and eto3 mutant seedlings, even though RNA gel-blot analysis demonstrated that the steady-state level of ACS mRNA was not increased, including that of a novel Arabidopsis ACS gene that was identified. Measurements of the conversion of ACC to ethylene by intact seedlings indicated that the mutations did not affect conjugation of ACC or the activity of ACC oxidase, the final step of ethylene biosynthesis. Taken together, these data suggest that the eto1 and eto3 mutations elevate ethylene biosynthesis by affecting the posttranscriptional regulation of ACS.
Fengquan Liu - One of the best experts on this subject based on the ideXlab platform.
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acc deaminase from lysobacter gummosus oh17 can promote root growth in oryza sativa nipponbare plants
Journal of Agricultural and Food Chemistry, 2018Co-Authors: Pedro Laborda, Jun Ling, Xian Chen, Fengquan LiuAbstract:Although Lysobacter species are a remarkable source of natural compounds with antibacterial and antifungal activities, the ability of these bacteria to produce plant growth promoters remains practically unknown. In this work, the ethylene precursor 1-Aminocyclopropane-1-Carboxylic Acid (ACC) has been isolated from the secretions of Lysobacter gummosus OH17, indicating the presence of an ACC deaminase, which was shown to be encoded in the gene peg_1256. The recombinant enzyme could not only deaminate ACC to provide 2-oxobutanoic Acid but also catalyzed the amination of the 2-oxobutanoic Acid, demonstrating, for the first time, that ACC deaminases can produce ACC. After the treatment of rice Oryza sativa Nipponbare plants with OH17 ACC deaminase, the ethylene production levels were 44% higher in comparison with the control experiments, allowing significant improvements in root, 10%, and stem, 14%, growth.
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ACC Deaminase from Lysobacter gummosus OH17 Can Promote Root Growth in Oryza sativa Nipponbare Plants
2018Co-Authors: Pedro Laborda, Jun Ling, Xian Chen, Fengquan LiuAbstract:Although Lysobacter species are a remarkable source of natural compounds with antibacterial and antifungal activities, the ability of these bacteria to produce plant growth promoters remains practically unknown. In this work, the ethylene precursor 1-Aminocyclopropane-1-Carboxylic Acid (ACC) has been isolated from the secretions of Lysobacter gummosus OH17, indicating the presence of an ACC deaminase, which was shown to be encoded in the gene peg_1256. The recombinant enzyme could not only deaminate ACC to provide 2-oxobutanoic Acid but also catalyzed the amination of the 2-oxobutanoic Acid, demonstrating, for the first time, that ACC deaminases can produce ACC. After the treatment of rice Oryza sativa Nipponbare plants with OH17 ACC deaminase, the ethylene production levels were 44% higher in comparison with the control experiments, allowing significant improvements in root, 10%, and stem, 14%, growth
Bernard R. Glick - One of the best experts on this subject based on the ideXlab platform.
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enhancement of growth and salt tolerance of red pepper seedlings capsicum annuum l by regulating stress ethylene synthesis with halotolerant bacteria containing 1 aminocyclopropane 1 carboxylic Acid deaminase activity
Plant Physiology and Biochemistry, 2011Co-Authors: M A Siddikee, Puneet Singh Chauhan, Bernard R. Glick, Woo Jong YimAbstract:Three 1-Aminocyclopropane-1-Carboxylic Acid (ACC) deaminase-producing halotolerant bacteria were isolated from West Coast soil of Yellow Sea, Incheon, South Korea and evaluated for their efficiency in improving red pepper plant growth under salt stress. The strains RS16, RS656 and RS111 were identified by 16S rRNA gene sequencing as Brevibacterium iodinum, Bacillus licheniformis and Zhihengliuela alba, respectively. Two hour exposure of 100, 150 and 200 mM NaCl stress on 8 day old red pepper seedlings caused 44, 64 and 74% increase ethylene production, while at 150 mM NaCl stress, inoculation of B. licheniformis RS656, Z. alba RS111, and Br. iodinum RS16 reduces ethylene production by 44, 53 and 57%, respectively. Similarly, 3 week old red pepper plants were subjected to salt stress for two weeks and approximately ∼50% reduction in growth recorded at 150 mM NaCl stress compared to negative control whereas bacteria inoculation significantly increase the growth compared to positive control. Salt stress also caused 1.3-fold reduction in the root/shoot dry weight ratio compared to the absence of salt while bacteria inoculation retained the biomass allocation similar to control plants. The salt tolerance index (ratio of biomass of salt stressed to non-stressed plant) was also significantly increased in inoculated plants compared to non-inoculated. Increase nutrient uptakes under salt stress by red pepper further evident that bacteria inoculation ameliorates salt stress effect. In summary, this study indicates that the use of ACC deaminase-producing halotolerant bacteria mitigates the salt stress by reducing salt stress-induced ethylene production on growth of red pepper plants.
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levels of acc and related compounds in exudate and extracts of canola seeds treated with acc deaminase containing plant growth promoting bacteria
Canadian Journal of Microbiology, 2001Co-Authors: Donna M Penrose, Bernard R. GlickAbstract:It was previously proposed that plant growth-promoting bacteria that possess 1-Aminocyclopropane-1-Carboxylic Acid (ACC) deaminase could utilize ACC that is present in the exudate of germinating ca...
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amelioration of flooding stress by acc deaminase containingplant growth promoting bacteria
Plant Physiology and Biochemistry, 2001Co-Authors: Varvara P Grichko, Bernard R. GlickAbstract:Seeds of wild-type tomato plants Lycopersicon esculentum (Solanaceae) cv. Heinz 902 were inoculated either with Enterobacter cloacae UW4, E. cloacae CAL2, Pseudomonas putida ATCC17399/pRKACC or P. putida ATCC17399/pRK415, the first three of these bacterial strains carrying and expressing the gene for 1-Aminocyclopropane-1-Carboxylic Acid (ACC) deaminase. When they were 55 d old, tomato plants were flooded for nine consecutive days before a number of physiological and biochemical parameters were assessed. Characteristics that were observed include root and shoot growth, epinastic curvature in leaf petioles, ACC deaminase activity, ethylene production, and leaf chlorophyll concentration. Tomato plants that were grown from seeds bacterized with organisms expressing ACC deaminase showed a substantial tolerance to flooding stress.
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effect of transferring 1 aminocyclopropane 1 carboxylic Acid acc deaminase genes into pseudomonas fluorescens strain cha0 and its gaca derivative cha96 on their growth promoting and disease suppressive capacities
Canadian Journal of Microbiology, 2000Co-Authors: Chunxia Wang, Bernard R. Glick, Edouard Knill, Genevieve DefagoAbstract:Pseudomonas fluorescens strain CHA0, a root colonizing bacterium, has a broad spectrum of biocontrol activity against plant diseases. However, strain CHA0 is unable to utilize 1-Aminocyclopropane-1-Carboxylic Acid (ACC), the immediate precursor of plant ethylene, as a sole source of nitrogen. This suggests that CHA0 does not contain the enzyme ACC deaminase, which cleaves ACC to ammonia and α-ketobutyrate, and was previously shown to promote root elongation of plant seedlings treated with bacteria containing this enzyme. An ACC deaminase gene, together with its regulatory region, was transferred into P. fluorescens strains CHA0 and CHA96, a global regulatory gacA mutant of CHA0. ACC deaminase activity was expressed in both CHA0 and CHA96. Transformed strains with ACC deaminase activity increased root length of canola plants under gnotobiotic conditions, whereas strains without this activity had no effect. Introduction of ACC deaminase genes into strain CHA0 improved its ability to protect cucumber against...
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1 aminocyclopropane 1 carboxylic Acid deaminase mutants of the plant growth promoting rhizobacterium pseudomonas putida gr12 2 do not stimulate canola root elongation
Canadian Journal of Microbiology, 1994Co-Authors: Bernard R. Glick, Christian B Jacobson, Melinda M K Schwarze, J. J. PasternakAbstract:The plant growth promoting rhizobacterium Pseudomonas putida GR12-2 was mutagenized with nitrosoguanidine and three separate mutants that were unable to utilize 1-Aminocyclopropane-1-Carboxylic Acid (ACC) as a sole nitrogen source were selected. These mutants are devoid of the ACC deaminase activity that is present in wild-type P. putida GR12-2 cells. Only wild-type cells, but not any of the ACC deaminase mutants, promoted root elongation of developing canola seedlings under gnotobiotic conditions. These results are interpreted in terms of a model in which P. putida GR12-2 promotes root elongation by binding to germinating seeds and sequesters and hydrolyzes some of the unbound ACC, thereby lowering the level of ACC and hence the endogenous ethylene concentration, allowing the roots to grow longer.Key words: 1-aminocyclopropane-1-carboxylate, ACC, plant growth promoting rhizobacteria, PGPR, ACC deaminase, bacterial fertilizer.
Adi Avni - One of the best experts on this subject based on the ideXlab platform.
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A Novel Plant Cysteine Protease Has a Dual Function as a Regulator of 1-Aminocyclopropane-1-Carboxylic Acid Synthase Gene Expression
The Plant Cell, 2005Co-Authors: Noa Matarasso, Silvia Schuster, Adi AvniAbstract:The hormone ethylene influences plant growth, development, and some defense responses. The fungal elicitor Ethylene-Inducing Xylanase (EIX) elicits ethylene biosynthesis in tomato (Lycopersicon esculentum) and tobacco (Nicotiana tabacum) leaves by induction of 1-aminocyclopropane-1-caboxylic Acid synthase (Acs) gene expression. A minimal promoter element in the LeAcs2 gene required for EIX responsiveness was defined by deletion analysis in transgenic tomato plants. The sequence between –715 and –675 of the tomato Acs2 gene was found to be essential for induction by EIX. A Cys protease (LeCp) was isolated that specifically binds to this cis element in vitro. Ectopic expression of LeCp in tomato leaves induced the expression of Acs2. Moreover, chromatin immunoprecipitation showed that LeCp binds in vivo to the Acs promoter. We propose a mechanism for the dual function of the LeCp protein. The protease acts enzymatically in the cytoplasm. Then, upon signaling, a small ubiquitin-related modifier protein binds to it, enabling entrance into the nucleus, where it acts as a transcription factor. Thus, LeCp can be considered a dual-function protein, having enzymatic activity and, upon elicitor signaling, exhibiting transcriptional factor activity that induces LeAcs2 expression.
Puneet Singh Chauhan - One of the best experts on this subject based on the ideXlab platform.
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exploitation of agro climatic environment for selection of 1 aminocyclopropane 1 carboxylic Acid acc deaminase producing salt tolerant indigenous plant growth promoting rhizobacteria
Microbiological Research, 2017Co-Authors: Sankalp Misra, Vijay Kant Dixit, Gyanendra Dviwedi, Sumit Yadav, Shashank Kumar Mishra, Alok Lehri, Mohammad Haneef Khan, Puneet Singh ChauhanAbstract:A comprehensive survey for 09 agro-climatic zones of Uttar Pradesh, India was conducted to isolate and characterize salt tolerant 1-Aminocyclopropane-1-Carboxylic Acid (ACC) deaminase possessing plant growth promoting (PGP) rhizobacteria for salt stress amelioration in rice. Here, we have isolated 1125 bacteria having the ability to tolerate 1M NaCl and out of those, 560 were screened for utilizing ACC as sole nitrogen source. 560 isolates were subjected for bacteria coated seed germination assay under 100mM salt (NaCl) stress resulting to 77 isolates which were further evaluated for seed germination assay, PGP and abiotic stress tolerance ability in vitro. This evaluation revealed 15 potent rhizobacteria representing each agro-climatic zone and salt stress mitigation in vitro. In particular, the biomass obtained for bacteria coated rice seedlings were corroborated with the performance of isolates exhibiting maximum average indole acetic Acid (IAA) production respective to the agro-climatic zone. Surprisingly based on 16S rRNA, much of the propitious isolates belonged to same specific epithet exhibited variedly in their characteristics. Overall, Bacillus spp. was explored as dominant genera in toto with highest distribution in Western Plain zone followed by Central zone. Therefore, this study provides a counter-intuitive perspective of selection of native microflora for their multifarious PGP and abiotic stress tolerance abilities based on the agro-climatic zones to empower the establishment and development of more suitable inoculants for their application in agriculture under local stress environments.
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regulation of ethylene biosynthesis under salt stress in red pepper capsicum annuum l by 1 aminocyclopropane 1 carboxylic Acid acc deaminase producing halotolerant bacteria
Journal of Plant Growth Regulation, 2012Co-Authors: M A Siddikee, Puneet Singh Chauhan, Tongmin SaAbstract:The present study was carried out to understand the mechanism of salt stress amelioration in red pepper plants by inoculation of 1-Aminocyclopropane-1-Carboxylic Acid (ACC) deaminase-producing halotolerant bacteria. In general, ethylene production, ACC concentration, ACC synthase (ACS), and ACC oxidase (ACO) enzyme activities increased with increasing levels of salt stress. Treatment with halotolerant bacteria reduced ethylene production by 47–64%, ACC concentration by 47–55% and ACO activity by 18–19% in salt-stressed (150 mmol NaCl) red pepper seedlings compared to uninoculated controls. ACS activity was lower in red pepper seedlings treated with Bacillus aryabhattai RS341 but higher in seedlings treated with Brevibacterium epidermidis RS15 (44%) and Micrococcus yunnanensis RS222 (23%) under salt-stressed conditions as compared to uninoculated controls. A significant increase was recorded in red pepper plant growth under salt stress when treated with ACC deaminase-producing halotolerant bacteria as compared to uninoculated controls. The results of this study collectively suggest that salt stress enhanced ethylene production by increasing enzyme activities of the ethylene biosynthetic pathway. Inoculation with ACC deaminase-producing halotolerant bacteria plays an important role in ethylene metabolism, particularly by reducing the ACC concentration, although a direct effect on reducing ACO activity was also observed. It is suggested that growth promotion in inoculated red pepper plants under inhibitory levels of salt stress is due to ACC deaminase activity present in the halotolerant bacteria.
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enhancement of growth and salt tolerance of red pepper seedlings capsicum annuum l by regulating stress ethylene synthesis with halotolerant bacteria containing 1 aminocyclopropane 1 carboxylic Acid deaminase activity
Plant Physiology and Biochemistry, 2011Co-Authors: M A Siddikee, Puneet Singh Chauhan, Bernard R. Glick, Woo Jong YimAbstract:Three 1-Aminocyclopropane-1-Carboxylic Acid (ACC) deaminase-producing halotolerant bacteria were isolated from West Coast soil of Yellow Sea, Incheon, South Korea and evaluated for their efficiency in improving red pepper plant growth under salt stress. The strains RS16, RS656 and RS111 were identified by 16S rRNA gene sequencing as Brevibacterium iodinum, Bacillus licheniformis and Zhihengliuela alba, respectively. Two hour exposure of 100, 150 and 200 mM NaCl stress on 8 day old red pepper seedlings caused 44, 64 and 74% increase ethylene production, while at 150 mM NaCl stress, inoculation of B. licheniformis RS656, Z. alba RS111, and Br. iodinum RS16 reduces ethylene production by 44, 53 and 57%, respectively. Similarly, 3 week old red pepper plants were subjected to salt stress for two weeks and approximately ∼50% reduction in growth recorded at 150 mM NaCl stress compared to negative control whereas bacteria inoculation significantly increase the growth compared to positive control. Salt stress also caused 1.3-fold reduction in the root/shoot dry weight ratio compared to the absence of salt while bacteria inoculation retained the biomass allocation similar to control plants. The salt tolerance index (ratio of biomass of salt stressed to non-stressed plant) was also significantly increased in inoculated plants compared to non-inoculated. Increase nutrient uptakes under salt stress by red pepper further evident that bacteria inoculation ameliorates salt stress effect. In summary, this study indicates that the use of ACC deaminase-producing halotolerant bacteria mitigates the salt stress by reducing salt stress-induced ethylene production on growth of red pepper plants.
