The (p)ppGpp-mediated stringent response regulatory system globally inhibits primary metabolism and activates secondary metabolism in Pseudomonas protegens H78

2020 ◽  
Vol 104 (7) ◽  
pp. 3061-3079 ◽  
Author(s):  
Lingyu Wu ◽  
Zheng Wang ◽  
Yejun Guan ◽  
Xianqing Huang ◽  
Huimin Shi ◽  
...  
Keyword(s):  
Secondary Metabolism ◽  
Regulatory System ◽  
Stringent Response ◽  
Primary Metabolism

scholarly journals Secondary Metabolism and Interspecific Competition Affect Accumulation of Spontaneous Mutants in the GacS-GacA Regulatory System in Pseudomonas protegens

mBio ◽  
2018 ◽  
Vol 9 (1) ◽  
Author(s):  
Qing Yan ◽  
Lucas D. Lopes ◽  
Brenda T. Shaffer ◽  
Teresa A. Kidarsa ◽  
Oliver Vining ◽  
...  
Keyword(s):  
Interspecific Competition ◽  
Secondary Metabolism ◽  
Antibiotic Production ◽  
Regulatory System ◽  
Antibiotic Biosynthesis ◽  
Primary Metabolism ◽  
Natural Environments ◽  
Trade Off ◽  
Pure Cultures ◽  
Spontaneous Mutants

ABSTRACTSecondary metabolites are synthesized by many microorganisms and provide a fitness benefit in the presence of competitors and predators. Secondary metabolism also can be costly, as it shunts energy and intermediates from primary metabolism. InPseudomonasspp., secondary metabolism is controlled by the GacS-GacA global regulatory system. Intriguingly, spontaneous mutations ingacSorgacA(Gac−mutants) are commonly observed in laboratory cultures. Here we investigated the role of secondary metabolism in the accumulation of Gac−mutants inPseudomonas protegensstrain Pf-5. Our results showed that secondary metabolism, specifically biosynthesis of the antimicrobial compound pyoluteorin, contributes significantly to the accumulation of Gac−mutants. Pyoluteorin biosynthesis, which poses a metabolic burden on the producer cells, but not pyoluteorin itself, leads to the accumulation of the spontaneous mutants. Interspecific competition also influenced the accumulation of the Gac−mutants: a reduced proportion of Gac−mutants accumulated whenP. protegensPf-5 was cocultured withBacillus subtilisthan in pure cultures of strain Pf-5. Overall, our study associated a fitness trade-off with secondary metabolism, with metabolic costs versus competitive benefits of production influencing the evolution ofP. protegens, assessed by the accumulation of Gac−mutants.IMPORTANCEMany microorganisms produce antibiotics, which contribute to ecologic fitness in natural environments where microbes constantly compete for resources with other organisms. However, biosynthesis of antibiotics is costly due to the metabolic burdens of the antibiotic-producing microorganism. Our results provide an example of the fitness trade-off associated with antibiotic production. Under noncompetitive conditions, antibiotic biosynthesis led to accumulation of spontaneous mutants lacking a master regulator of antibiotic production. However, relatively few of these spontaneous mutants accumulated when a competitor was present. Results from this work provide information on the evolution of antibiotic biosynthesis and provide a framework for their discovery and regulation.

scholarly journals Metabolite profiling during graft union formation reveals the reprogramming of primary metabolism and the induction of stilbene synthesis at the graft interface in grapevine

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Duyên Prodhomme ◽  
Josep Valls Fonayet ◽  
Cyril Hévin ◽  
Céline Franc ◽  
Ghislaine Hilbert ◽  
...  
Keyword(s):  
Amino Acids ◽  
Secondary Metabolism ◽  
Fruits And Vegetables ◽  
Cell Formation ◽  
Union Formation ◽  
Primary Metabolism ◽  
Graft Union ◽  
Primary And Secondary Metabolites ◽  
Primary And Secondary Metabolism ◽  
Graft Interface

Abstract Background Grafting with rootstocks is essential for the culture of many perennial fruit crops and is increasing being used in the production of annual fruits and vegetables. Our previous work based on microarrays showed that transcripts encoding enzymes of both primary and secondary metabolism were differentially expressed during graft union formation in both homo-grafts (a genotype grafted with itself) and hetero-grafts (two different genotypes grafted together). The aim of this study was to profile primary and secondary metabolites, and quantify the activity of phenylalanine ammonia lyase (PAL) and neutral invertase (NI) in the scion and rootstock tissues and the graft interface of homo and hetero-grafts of grapevine 1 month after grafting. Table-top grafting was done on over-wintering stems (canes) of grapevine and the graft interface tissues (containing some woody stem tissues and callus) were compared to the surrounding rootstock and scion tissues. The objective was to identify compounds involved in graft union formation and hetero-grafting responses. Results A total of 54 compounds from primary and secondary metabolism (19 amino acids, five primary and 30 secondary compounds metabolites) and the activity of two enzymes were measured. The graft interface was associated with an increase in the accumulation of the branched-chain amino acids, basic amino acids, certain stilbene compounds and higher PAL and NI activity in comparison to the surrounding woody stem tissues. Some amino acids and stilbenes were identified as being accumulated differently between the graft interfaces of the scion/rootstock combinations in a manner which was unrelated to their concentrations in the surrounding woody stem tissues. Conclusions This study revealed the modification of primary metabolism to support callus cell formation and the stimulation of stilbene synthesis at the graft interface, and how these processes are modified by hetero-grafting. Knowledge of the metabolites and/or enzymes required for successful graft union formation offer us the potential to identify markers that could be used by nurseries and researchers for selection and breeding purposes.

scholarly journals Identification of butenolide regulatory system controlling secondary metabolism in Streptomyces albus J1074

2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Yousra Ahmed ◽  
Yuriy Rebets ◽  
Bogdan Tokovenko ◽  
Elke Brötz ◽  
Andriy Luzhetskyy
Keyword(s):  
Secondary Metabolism ◽  
Regulatory System ◽  
Streptomyces Albus ◽  
Streptomyces Albus J1074

scholarly journals Similar solutions to a common challenge: Regulation of genes encoding Ralstonia solanacearum xanthine dehydrogenase

2021 ◽  
Author(s):  
Smitha Sivapragasam ◽  
Arpita Ghosh ◽  
Sanjay Kumar ◽  
Danté T Johnson ◽  
Anne Grove
Keyword(s):  
Transcription Factor ◽  
Ralstonia Solanacearum ◽  
Fluorescent Protein ◽  
Bacterial Species ◽  
Regulatory System ◽  
Stringent Response ◽  
Xanthine Dehydrogenase ◽  
Guanosine Monophosphate ◽  
Purine Salvage ◽  
Genes Encoding

Abstract The stringent response involves accumulation of (p)ppGpp, and it ensures that survival is prioritized. Production of (p)ppGpp requires purine synthesis, and upregulation of an operon that encodes the purine salvage enzyme xanthine dehydrogenase (Xdh) has been observed during stringent response in some bacterial species, where direct binding of ppGpp to a TetR-family transcription factor is responsible for increased xdh gene expression. We show here that the plant pathogen Ralstonia solanacearum has a regulatory system in which the LysR-family transcription factor XanR controls expression of the xan operon; this operon encodes Xdh as well as other enzymes involved in purine salvage, which favor accumulation of xanthine. XanR bound upstream of the xan operon, a binding that was attenuated on addition of either ppGpp or cyclic di-guanosine monophosphate (c-di-GMP). Using a reporter in which enhanced green fluorescent protein (EGFP) is expressed under control of a modified xan promoter, XanR was shown to repress EGFP production. Our data suggest that R. solanacearum features a regulatory mechanism in which expression of genes encoding purine salvage enzymes is controlled by a transcription factor that belongs to a different protein family, yet performs similar regulatory functions.

scholarly journals Chemical Perturbation of Secondary Metabolism Demonstrates Important Links to Primary Metabolism

2012 ◽  
Vol 19 (8) ◽  
pp. 1020-1027 ◽  
Author(s):  
Arryn Craney ◽  
Cory Ozimok ◽  
Sheila Marie Pimentel-Elardo ◽  
Alfredo Capretta ◽  
Justin R. Nodwell
Keyword(s):  
Secondary Metabolism ◽  
Primary Metabolism ◽  
Chemical Perturbation

scholarly journals RECENT ADVANCES IN APPLICATIONS OF ACTIVE CONSTITUENTS OF SELECTED MEDICINAL PLANTS OF DHOFAR, SULTANATE OF OMAN

2018 ◽  
Vol 11 (4) ◽  
pp. 28
Author(s):  
Israr Ul Hassan ◽  
Mohammed Idrees ◽  
Gowhar Ahmad Naikoo ◽  
Luay Rashan ◽  
Abdelbary Elhissi ◽  
...  
Keyword(s):  
Medicinal Plants ◽  
Secondary Metabolism ◽  
Review Article ◽  
Wild Plants ◽  
Primary Metabolism ◽  
Plant Biodiversity ◽  
Sultanate Of Oman ◽  
Active Constituents ◽  
Medicinal Properties ◽  
Selection Of

 The Dhofar region of Oman is extremely opulent in plant biodiversity in comparison to other parts of the country. Most of the cultivated, medicinal and wild plants of the region are available in the mountainous side and hilly areas of Dhofar. The plants produce products from primary metabolism and others from secondary metabolism. On the basis of active constituents plants can be categorized into two groups:1. Medicinal plants and2. Aromatic plants.Over 250 complex chemicals have been recognized and extracted from herbal sources. In this review article, we discuss a selection of medicinal plants of the Dhofar region of Oman which are rich in active constituents and through recent reports discuss the application of the most active constituents. Among the medicinal plants of the Dhofar region, frankincense is also a well-known indicator of the region and has a unique position through its medicinal properties of its oil and gum resin.

Two Bacterial Group II Phosphopantetheinyl Transferases Involved in Both Primary Metabolism and Secondary Metabolism

2014 ◽  
Vol 70 (3) ◽  
pp. 390-397 ◽  
Author(s):  
Yue-Yue Wang ◽  
Xiao-Sheng Zhang ◽  
Ni-Ni Ren ◽  
Yuan-Yang Guo ◽  
Xin-Hang Jiang ◽  
...  
Keyword(s):  
Secondary Metabolism ◽  
Primary Metabolism ◽  
Bacterial Group ◽  
Group Ii ◽  
Phosphopantetheinyl Transferases

scholarly journals Contributions of Sinorhizobium meliloti Transcriptional Regulator DksA to Bacterial Growth and Efficient Symbiosis with Medicago sativa

2016 ◽  
Vol 198 (9) ◽  
pp. 1374-1383 ◽  
Author(s):  
Kathrin Wippel ◽  
Sharon R. Long
Keyword(s):  
Medicago Sativa ◽  
Host Plant ◽  
Sinorhizobium Meliloti ◽  
Coiled Coil ◽  
Regulatory System ◽  
Stringent Response ◽  
Transcriptional Regulator ◽  
Molecular Control ◽  
Content Type ◽  
Nitrogen Fixation Activity

ABSTRACTThe stringent response, mediated by the (p)ppGpp synthetase RelA and the RNA polymerase-binding protein DksA, is triggered by limiting nutrient conditions. For some bacteria, it is involved in regulation of virulence. We investigated the role of two DksA-like proteins from the Gram-negative nitrogen-fixing symbiontSinorhizobium melilotiin free-living culture and in interaction with its host plantMedicago sativa. The two paralogs, encoded by the genesSMc00469andSMc00049, differ in the constitution of two major domains required for function in canonical DksA: the DXXDXA motif at the tip of a coiled-coil domain and a zinc finger domain. Using mutant analyses of single, double, and triple deletions forSMc00469(designateddksA),SMc00049, andrelA, we found that the ΔdksAmutant but not the ΔSMc00049mutant showed impaired growth on minimal medium, reduced nodulation on the host plant, and lower nitrogen fixation activity in early nodules, while itsnodgene expression was normal. The ΔrelAmutant showed severe pleiotropic phenotypes under all conditions tested. OnlyS. melilotidksAcomplemented the metabolic defects of anEscherichia coli dksAmutant. Modifications of the DXXDXA motif in SMc00049 failed to establish DksA function. Our results imply a role for transcriptional regulator DksA in theS. meliloti-M. sativasymbiosis.IMPORTANCEThe stringent response is a bacterial transcription regulation process triggered upon nutritional stress.Sinorhizobium meliloti, a soil bacterium establishing agriculturally important root nodule symbioses with legume plants, undergoes constant molecular adjustment during host interaction. Analyzing the components of the stringent response in this alphaproteobacterium helps understand molecular control regarding the development of plant interaction. Using mutant analyses, we describe how the lack of DksA influences symbiosis withMedicago sativaand show that a second paralogousS. melilotiprotein cannot substitute for this missing function. This work contributes to the field by showing the similarities and differences ofS. melilotiDksA-like proteins to orthologs from other species, adding information to the diversity of the stringent response regulatory system.

scholarly journals The Stringent Response Is Essential for Pseudomonas aeruginosa Virulence in the Rat Lung Agar Bead and Drosophila melanogaster Feeding Models of Infection

2011 ◽  
Vol 79 (10) ◽  
pp. 4094-4104 ◽  
Author(s):  
Stefanie L. Vogt ◽  
Christopher Green ◽  
Katarzyna M. Stevens ◽  
Brad Day ◽  
David L. Erickson ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Drosophila Melanogaster ◽  
Double Mutant ◽  
Regulatory System ◽  
Stringent Response ◽  
Insertion Mutation ◽  
Virulence Determinants ◽  
Rat Lung ◽  
Content Type

ABSTRACTThe stringent response is a regulatory system that allows bacteria to sense and adapt to nutrient-poor environments. The central mediator of the stringent response is the molecule guanosine 3′,5′-bispyrophosphate (ppGpp), which is synthesized by the enzymes RelA and SpoT and which is also degraded by SpoT. Our laboratory previously demonstrated that arelAmutant ofPseudomonas aeruginosa, the principal cause of lung infections in cystic fibrosis patients, was attenuated in virulence in aDrosophila melanogasterfeeding model of infection. In this study, we examined the role ofspoTinP. aeruginosavirulence. We generated an insertion mutation inspoTwithin the previously constructedrelAmutant, thereby producing a ppGpp-devoid strain. TherelA spoTdouble mutant was unable to establish a chronic infection inD. melanogasterand was also avirulent in the rat lung agar bead model of infection, a model in which therelAmutant is fully virulent. Synthesis of the virulence determinants pyocyanin, elastase, protease, and siderophores was impaired in therelA spoTdouble mutant. This mutant was also defective in swarming and twitching, but not in swimming motility. TherelA spoTmutant and, to a lesser extent, therelAmutant were less able to withstand stresses such as heat shock and oxidative stress than the wild-type strain PAO1, which may partially account for the inability of therelA spoTmutant to successfully colonize the rat lung. Our results indicate that the stringent response, and SpoT in particular, is a crucial regulator of virulence processes inP. aeruginosa.

scholarly journals Analysis of the transcriptome of the needles and bark of Pinus radiata induced by bark stripping and methyl jasmonate

BMC Genomics ◽  
2022 ◽  
Vol 23 (1) ◽  
Author(s):  
J. S. Nantongo ◽  
B. M. Potts ◽  
T. Frickey ◽  
E. Telfer ◽  
H. Dungey ◽  
...  
Keyword(s):  
Methyl Jasmonate ◽  
Secondary Metabolism ◽  
Differential Expression ◽  
Pinus Radiata ◽  
Plant Responses ◽  
Primary Metabolism ◽  
Bark Stripping ◽  
Transcriptional Responses ◽  
Down Regulation ◽  
Chemical Defences

Abstract Background Plants are attacked by diverse insect and mammalian herbivores and respond with different physical and chemical defences. Transcriptional changes underlie these phenotypic changes. Simulated herbivory has been used to study the transcriptional and other early regulation events of these plant responses. In this study, constitutive and induced transcriptional responses to artificial bark stripping are compared in the needles and the bark of Pinus radiata to the responses from application of the plant stressor, methyl jasmonate. The time progression of the responses was assessed over a 4-week period. Results Of the 6312 unique transcripts studied, 86.6% were differentially expressed between the needles and the bark prior to treatment. The most abundant constitutive transcripts were related to defence and photosynthesis and their expression did not differ between the needles and the bark. While no differential expression of transcripts were detected in the needles following bark stripping, in the bark this treatment caused an up-regulation and down-regulation of genes associated with primary and secondary metabolism. Methyl jasmonate treatment caused differential expression of transcripts in both the bark and the needles, with individual genes related to primary metabolism more responsive than those associated with secondary metabolism. The up-regulation of genes related to sugar break-down and the repression of genes related with photosynthesis, following both treatments was consistent with the strong down-regulation of sugars that has been observed in the same population. Relative to the control, the treatments caused a differential expression of genes involved in signalling, photosynthesis, carbohydrate and lipid metabolism as well as defence and water stress. However, non-overlapping transcripts were detected between the needles and the bark, between treatments and at different times of assessment. Methyl jasmonate induced more transcriptional responses in the bark than bark stripping, although the peak of expression following both treatments was detected 7 days post treatment application. The effects of bark stripping were localised, and no systemic changes were detected in the needles. Conclusion There are constitutive and induced differences in the needle and bark transcriptome of Pinus radiata. Some expression responses to bark stripping may differ from other biotic and abiotic stresses, which contributes to the understanding of plant molecular responses to diverse stresses. Whether the gene expression changes are heritable and how they differ between resistant and susceptible families identified in earlier studies needs further investigation.

Sign in / Sign up

Export Citation Format

Share Document