Role of the carbon source in regulating chloramphenicol production by Streptomyces venezuelae: studies in batch and continuous cultures

1988 ◽  
Vol 34 (11) ◽  
pp. 1217-1223 ◽  
Author(s):  
R. K. Bhatnagar ◽  
J. L. Doull ◽  
L. C. Vining
Keyword(s):  
Carbon Source ◽  
Glucose Concentration ◽  
Specific Activity ◽  
Antibiotic Production ◽  
Enzyme Synthesis ◽  
Antibiotic Biosynthesis ◽  
Synthetase Activity ◽  
Streptomyces Venezuelae ◽  
Batch Cultures ◽  
Chemostat Cultures

Both carbon- and nitrogen-limited media that supported a biphasic pattern of growth and chloramphenicol biosynthesis were devised for batch cultures of Streptomyces venezuelae. Where onset of the idiophase was associated with nitrogen depletion, a sharp peak of arylamine synthetase activity coincided with the onset of antibiotic production. The specific activity of the enzyme was highest when the carbon source in the medium was also near depletion at the trophophase–idiophase boundary. In media providing a substantial excess of carbon source through the idiophase, the peak specific activity was reduced by 75%, although the timing of enzyme synthesis was unaltered. Morever, chemostat cultures in which the growth rate was limited by the glucose concentration in the input medium failed to show a decrease in specific production of chloramphenicol as the steady-state intracellular glucose concentration was increased. The results suggest that a form of "carbon catabolite repression" regulates synthesis of chloramphenicol biosynthetic enzymes during a trophophase–idiophase transition induced by nitrogen starvation. However, this regulatory mechanism does not establish the timing of antibiotic biosynthesis and does not function during nitrogen-sufficient growth in the presence of excess glucose.

Metabolic control in Acinetobacter sp. I. Effect of C4 versus C2 and C3 substrates on isocitrate lyase synthesis

1970 ◽  
Vol 16 (8) ◽  
pp. 769-774 ◽  
Author(s):  
Norma J. Herman ◽  
Emily J. Bell
Keyword(s):  
Carbon Source ◽  
Phosphoenolpyruvate Carboxykinase ◽  
Specific Activity ◽  
Isocitrate Lyase ◽  
Tricarboxylic Acid Cycle ◽  
Glyoxylate Cycle ◽  
Enzyme Synthesis ◽  
Synthetase Activity ◽  
The Glyoxylate Cycle

The comparative effects of various substrates serving as sole carbon and energy source or as a supplemental nutrient on the synthesis of isocitrate lyase by a species of Acinetobacter have been investigated. Previous work has shown that succinate, as carbon source, allows some late, limited induction of enzyme synthesis. No increase in synthesis is seen above the basal level, however, in cultures growing in a medium containing L-malate as a sole carbon source. The addition of acetate to cultures growing in media containing either of the C4 intermediates results in rapid enzyme induction. Further, Acinetobacter grows very well in pyruvate medium and isocitrate lyase is synthesized to a significant extent, indicating that the glyoxylate cycle is acting anaplerotically under these conditions. Phosphoenolpyruvate synthetase activity has been demonstrated in this organism; levels comparable to those observed in Escherichia coli have been detected; the levels of NAD- and NADP-linked "malic enzyme" and phosphoenolpyruvate carboxykinase, enzymes functioning in C4 to C3 conversion, do not fluctuate with the various carbon sources tested; i.e. no correlation between the in vitro specific activity of these enzymes and the levels of isocitrate lyase activity may be made. All of the data are consistent with the hypothesis that, in this aerobic organism, as opposed to the facultative E. coli, the C4 intermediates of the tricarboxylic acid cycle may be more direct "coarse" control metabolites regulating the rate of the glyoxylate cycle.

Catabolite repression in Streptomyces venezuelae. Induction of β-galactosidase, chloramphenicol production, and intracellular cyclic adenosine 3′,5′-monophosphate concentrations

1982 ◽  
Vol 28 (3) ◽  
pp. 311-317 ◽  
Author(s):  
S. Chatterjee ◽  
L. C. Vining
Keyword(s):  
Carbon Source ◽  
Cyclic Nucleotide ◽  
Catabolite Repression ◽  
Marked Decrease ◽  
Nutrient Utilization ◽  
Sole Source ◽  
Glucose Measurement ◽  
Antibiotic Biosynthesis ◽  
Streptomyces Venezuelae ◽  
Production Pattern

Chloramphenicol production was studied in cultures of Streptomyces venezuelae growing in a simple buffered medium with ammonia as the nitrogen source and glucose, lactose, or a glucose–lactose mixture as the sole source of carbon. With each carbon source the antibiotic was formed during growth. In the glucose–lactose medium, the production pattern was biphasic; a marked decrease in the rate of synthesis was associated with depletion of glucose from the medium and a corresponding diauxie pause in growth. Cells of S. venezuelae contained an inducible β-galactosidase. Induction by lactose was suppressed by glucose. Measurement of the concentration of intracellular adenonsine 3′,5′-cyclic monophosphate during growth of cultures with glucose or a glucose–lactose mixture as the source of carbon showed no appreciable changes coinciding with depletion of glucose or the onset of chloramphenicol biosynthesis. It is concluded that the cyclic nucleotide does not mediate selective nutrient utilization or control antibiotic biosynthesis in this organism.

scholarly journals Role of the ptsN Gene Product in Catabolite Repression of the Pseudomonas putida TOL Toluene Degradation Pathway in Chemostat Cultures▿

2006 ◽  
Vol 72 (11) ◽  
pp. 7418-7421 ◽  
Author(s):  
Isabel Aranda-Olmedo ◽  
Patricia Marín ◽  
Juan L. Ramos ◽  
Silvia Marqués
Keyword(s):  
Carbon Source ◽  
Pseudomonas Putida ◽  
Gene Product ◽  
Catabolite Repression ◽  
Maximum Rate ◽  
Degradation Pathway ◽  
Toluene Degradation ◽  
Batch Cultures ◽  
Chemostat Cultures

ABSTRACT The Pseudomonas putida KT2440 TOL upper pathway is repressed under nonlimiting conditions in cells growing in chemostat with succinate as a carbon source. We show that the ptsN gene product IIANtr participates in this repression. Crc, involved in yeast extract-dependent repression in batch cultures, did not influence expression when cells were growing in a chemostat with succinate at maximum rate.

Suppression of nitrate utilization by ammonium and its relationship to chloramphenicol production in Streptomyces venezuelae

1984 ◽  
Vol 30 (6) ◽  
pp. 798-804 ◽  
Author(s):  
S. Shapiro ◽  
L. C. Vining
Keyword(s):  
Nitrate Reductase ◽  
Nitrogen Source ◽  
Specific Activity ◽  
Marked Change ◽  
Biomass Accumulation ◽  
Nitrogen Sources ◽  
Antibiotic Biosynthesis ◽  
Streptomyces Venezuelae ◽  
Ammonium Production ◽  
Fermentation Broths

Cultures of Streptomyces venezuelae grown in a medium containing glucose with mixtures of ammonium and nitrate as the nitrogen source produced chloramphenicol in a distinct idiophase that followed biomass accumulation. Analysis of fermentation broths showed that ammonium and nitrate were taken up consecutively by the organism. Measurements of nitrate reductase in the mycelium established that the enzyme was constitutive and that its specific activity did not increase during the period when ammonium was exhausted from the medium and nitrate was assimilated. The enzyme was neither repressed nor inhibited by ammonium. Production of chloramphenicol was also delayed until ammonium had been consumed and remained slow until subsequent depletion of nitrate. Arylamine synthetase, the initial enzyme in the pathway of antibiotic biosynthesis, showed no marked change in specific activity during utilization of the two nitrogen sources. The result suggests that the mechanism causing preferential utilization of ammonium does not simultaneously control the onset of chloramphenicol biosynthesis.

Glucose suppression of β-glucosidase activity in a chloramphenicol-producing strain of Streptomyces venezuelae

1982 ◽  
Vol 28 (6) ◽  
pp. 593-599 ◽  
Author(s):  
S. Chatterjee ◽  
L. C. Vining
Keyword(s):  
Amino Acids ◽  
Carbon Source ◽  
Deae Cellulose ◽  
The Other ◽  
Antibiotic Biosynthesis ◽  
Control Mechanisms ◽  
Streptomyces Venezuelae ◽  
Glucosidase Activity ◽  
Cell Extracts ◽  
Source Preferences

β-Glucosidase activity was induced in Streptomyces venezuelae during growth on cellobiose, gentiobiose, salicin, methyl β-glucoside, and p-nitrophenyl β-D-glucopyranoside. Activity in cell extracts was separated by DEAE-cellulose chromatography into two fractions differing in substrate preference. One component showed higher activity with, and was more strongly induced by, cellobiose; the other showed greater activity and inducibility with salicin. Addition of glucose to cultures severely depressed induction of β-glucosidase activity by cellobiose but not by salicin. Acetate and several amino acids inhibited induction by either substrate. The action of glucose was not reversed by cyclic AMP. Cultures of S. venezuelae using glucose, cellobiose, or a mixture of the two saccharides as their carbon source produced chloramphenicol during growth. In contrast with its effect on the induction of cellobiase activity, glucose did not suppress chloramphenicol production, indicating that the control mechanisms that establish carbon source preferences are not linked to those that regulate antibiotic biosynthesis in this organism.

scholarly journals The Phosin PptA Plays a Negative Role in the Regulation of Antibiotic Production in Streptomyces lividans

Antibiotics ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 325
Author(s):  
Noriyasu Shikura ◽  
Emmanuelle Darbon ◽  
Catherine Esnault ◽  
Ariane Deniset-Besseau ◽  
Delin Xu ◽  
...  
Keyword(s):  
Antibiotic Production ◽  
Streptomyces Lividans ◽  
Positive Control ◽  
Phosphate Limitation ◽  
Antibiotic Biosynthesis ◽  
Nudix Hydrolase ◽  
Energetic Stress ◽  
Accessory Factor ◽  
Negative Role ◽  
Weak Expression

In Streptomyces, antibiotic biosynthesis is triggered in phosphate limitation that is usually correlated with energetic stress. Polyphosphates constitute an important reservoir of phosphate and energy and a better understanding of their role in the regulation of antibiotic biosynthesis is of crucial importance. We previously characterized a gene, SLI_4384/ppk, encoding a polyphosphate kinase, whose disruption greatly enhanced the weak antibiotic production of Streptomyces lividans. In the condition of energetic stress, Ppk utilizes polyP as phosphate and energy donor, to generate ATP from ADP. In this paper, we established that ppk is co-transcribed with its two downstream genes, SLI_4383, encoding a phosin called PptA possessing a CHAD domain constituting a polyphosphate binding module and SLI_4382 encoding a nudix hydrolase. The expression of the ppk/pptA/SLI_4382 operon was shown to be under the positive control of the two-component system PhoR/PhoP and thus mainly expressed in condition of phosphate limitation. However, pptA and SLI_4382 can also be transcribed alone from their own promoter. The deletion of pptA resulted into earlier and stronger actinorhodin production and lower lipid content than the disruption of ppk, whereas the deletion of SLI_4382 had no obvious phenotypical consequences. The disruption of ppk was shown to have a polar effect on the expression of pptA, suggesting that the phenotype of the ppk mutant might be linked, at least in part, to the weak expression of pptA in this strain. Interestingly, the expression of phoR/phoP and that of the genes of the pho regulon involved in phosphate supply or saving were strongly up-regulated in pptA and ppk mutants, revealing that both mutants suffer from phosphate stress. Considering the presence of a polyphosphate binding module in PptA, but absence of similarities between PptA and known exo-polyphosphatases, we proposed that PptA constitutes an accessory factor for exopolyphosphatases or general phosphatases involved in the degradation of polyphosphates into phosphate.

scholarly journals Aeration and Stirring in Yarrowia lipolytica Lipase Biosynthesis during Batch Cultures with Waste Fish Oil as a Carbon Source

Fermentation ◽  
2021 ◽  
Vol 7 (2) ◽  
pp. 88
Author(s):  
Paulina Snopek ◽  
Dorota Nowak ◽  
Bartłomiej Zieniuk ◽  
Agata Fabiszewska
Keyword(s):  
Carbon Source ◽  
Fish Oil ◽  
Yarrowia Lipolytica ◽  
Lipolytic Activity ◽  
Culture Conditions ◽  
Agitation Speed ◽  
Oxygen Deficit ◽  
Shear Stresses ◽  
Process Selection ◽  
Batch Cultures

Yarrowia lipolytica is one of the most studied non-conventional forms of yeast, exhibiting a high secretory capacity and producing many industrially important and valuable metabolites. The yeast conceals a great biotechnological potential to synthesize organic acids, sweeteners, microbial oil, or fragrances. The vast majority of bioprocesses are carried out in bioreactors, where suitable culture conditions are provided. In the current study, the effect of agitation speed (200–600 rpm) and air flow rate (0.0375–2.0 dm3/(dm3 × min)) on the biomass yield and lipase activity of Y. lipolytica KKP 379 is analyzed in a growth medium containing waste fish oil. The increase of aeration intensity limited the period of oxygen deficit in the medium. Simultaneously, an increase in lipolytic activity was observed from 2.09 U/cm3 to 14.21 U/cm3; however, an excessive agitation speed likely caused oxidative or shear stresses, and a reduction in lipolytic activity was observed. Moreover, it is confirmed that the synthesis of lipases is related to oxygen consumption, pH, and the yeast growth phase, and appropriate process selection may provide two advantages, namely, the maximum use of the waste carbon source and the production of lipolytic enzymes that are valuable in many industries.

Fresh approaches to antibiotic production

1980 ◽  
Vol 290 (1040) ◽  
pp. 313-328 ◽  
Keyword(s):  
Polyethylene Glycol ◽  
Plant Pathogens ◽  
Growth Promotion ◽  
Antibiotic Production ◽  
Strain Improvement ◽  
Antibiotic Biosynthesis ◽  
Yield Improvement ◽  
Acquired Drug Resistance ◽  
Intensive Farming ◽  
New Antibiotics

New antibiotics are needed, ( a ) to control diseases that are refractory to existing ones either because of intrinsic or acquired drug resistance of the pathogen or because inhibition of the disease is difficult, at present, without damaging the host (fungal and viral diseases, and tumours), ( b ) for the control of plant pathogens and of invertebrates such as helminths, insects, etc., and ( c ) for growth promotion in intensive farming. Numerous new antibiotics are still being obtained from wild microbes, especially actinomycetes. Chemical modification of existing compounds has also had notable success. Here we explore the uses, actual and potential, of genetics to generate new antibiotics and to satisfy the ever-present need to increase yield. Yield improvement has depended in the past on mutation and selection, combined with optimization of fermentation conditions. Progress would be greatly accelerated by screening random recombinants between divergent high-yielding strains. Strain improvement may also be possible by the introduction of extra copies of genes of which the products are rate-limiting, or of genes conferring beneficial growth characteristics. Although new antibiotics can be generated by mutation, either through disturbing known biosyntheses or by activating ‘silent’ genes, we see more promise in interspecific recombination between strains producing different secondary metabolites, generating producers of ‘hybrid’ antibiotics. As with proposals for yield improvement, there are two major strategies for obtaining interesting recombinants of this kind: random recombination between appropriate strains, or the deliberate movement of particular biosynthetic abilities between strains. The development of protoplast technology in actinomycetes, fungi and bacilli has been instrumental in bringing these idealized strategies to the horizon. Protoplasts of the same or different species can be induced to fuse by polyethylene glycol. At least in intraspecific fusion of streptomycetes, random and high frequency recombination follows. Protoplasts can also be used as recipients for isolated DNA, again in the presence of polyethylene glycol, so that the deliberate introduction of particular genes into production strains can be realistically envisaged. Various kinds of DNA cloning vectors are being developed to this end. Gene cloning techniques also offer rich possibilities for the analysis of the genetic control of antibiotic biosynthesis, knowledge of which is, at present, minimal. The information that should soon accrue can be expected to have profound effects on the application of genetics to industrial microbiology.

Diguanylate cyclase and phosphodiesterase interact to maintain the specificity of c-di-GMP signaling in the regulation of antibiotic synthesis in Lysobacter enzymogenes

2021 ◽  
Author(s):  
Gaoge Xu ◽  
Lichuan Zhou ◽  
Guoliang Qian ◽  
Fengquan Liu
Keyword(s):  
Direct Evidence ◽  
Antibiotic Production ◽  
Indirect Evidence ◽  
Second Messenger ◽  
Antibiotic Biosynthesis ◽  
Diguanylate Cyclase ◽  
Signaling Specificity ◽  
Lysobacter Enzymogenes ◽  
Subsequent Investigation ◽  
Diguanylate Cyclases

Cyclic dimeric GMP (c-di-GMP) is a universal second messenger in bacteria. The large number of c-di-GMP-related diguanylate cyclases (DGCs), phosphodiesterases (PDEs) and effectors are responsible for the complexity and dynamics of c-di-GMP signaling. Some of these components deploy various methods to avoid undesired crosstalk to maintain signaling specificity. Synthesis of the antibiotic HSAF ( H eat S table A ntifungal F actor) in Lysobacter enzymogenes is regulated by a specific c-di-GMP signaling pathway that includes a PDE LchP and a c-di-GMP effector Clp (also a transcriptional regulator). In the present study, from among 19 DGCs, we identified a diguanylate cyclase, LchD, which participates in this pathway. Subsequent investigation indicates that LchD and LchP physically interact and that the catalytic center of LchD is required for both the formation of the LchD-LchP complex and HSAF production. All the detected phenotypes support that LchD and LchP dispaly local c-di-GMP signaling to regulate HSAF biosynthesis. Although direct evidence is lacking, our investigation, which shows that the interaction between a DGC and a PDE maintains the specificity of c-di-GMP signaling, suggests the possibility of the existence of local c-di-GMP pools in bacteria. Importance Cyclic dimeric GMP (c-di-GMP) is a universal second messenger in bacteria. Signaling of c-di-GMP is complex and dynamic, and it is mediated by a large number of components, including c-di-GMP synthases (diguanylate cyclases. DGCs), c-di-GMP degrading enzymes (phosphodiesterases, PDEs), and c-di-GMP effectors. These components deploy various methods to avoid undesired crosstalk to maintain signaling specificity. In the present study, we identified a DGC that interacted with a PDE to specifically regulate antibiotic biosynthesis in L. enzymogenes . We provide direct evidence to show that the DGC and PDE form a complex, and also indirect evidence to argue that they may balance a local c-di-GMP pool to control the antibiotic production. The results represent an important finding regarding the mechanism of a pair of DGC and PDE to control the expression of specific c-di-GMP signaling pathways.

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