Sulfatase regulation and antibiotic synthesis in Cephalosporium acremonium

1969 ◽  
Vol 15 (2) ◽  
pp. 175-181 ◽  
Author(s):  
David W. Dennen ◽  
Diane D. Carver
Keyword(s):  
Amino Acid ◽  
Culture Medium ◽  
Sulfur Compounds ◽  
Cephalosporin C ◽  
Cephalosporium Acremonium ◽  
Antibiotic Synthesis ◽  
Cellular Processes ◽  
High Level ◽  
Sulfur Containing ◽  
Sulfur Containing Compounds

The sulfatase of Cephalosporium acremonium is regulated by exogenous sulfur compounds, repressed in cells in 0.02 M sulfate, and derepressed in 5 × 10−4 M sulfate. Organic sulfur sources, such as cysteine, homocysteine, and methionine, derepress the enzyme in varying degrees while the latter amino acid is also required for maximum synthesis of the antibiotics cephalosporin C and penicillin N. Sulfatase-repressed cells transferred from sulfate to methionine-containing medium produce a high level of these antibiotics in the culture medium and a proportionate derepression of the sulfatase. Cycloheximide inhibits sulfatase derepression in cultures transferred from sulfate to methionine medium while having negligible effect on antibiotic synthesis. Mutant cultures of C. acremonium, with an increased potential to synthesize sulfur-containing antibiotics, have decreased ability to degrade methionine for other cellular requirements and sulfatase derepression is proportionately increased. The sulfatase is thus regulated by the biosynthesis of cephalosporin C and penicillin N at the expense of sulfur-containing compounds required for other cellular processes.

scholarly journals Sulfur and Sulfur Compounds in Plant Defence

2012 ◽  
Vol 7 (3) ◽  
pp. 1934578X1200700 ◽  
Author(s):  
Ifeanyi D. Nwachukwu ◽  
Alan J. Slusarenko ◽  
Martin C. H. Gruhlke
Keyword(s):  
Natural Products ◽  
New Technologies ◽  
Plant Defence ◽  
Sulfur Compounds ◽  
Oxidation States ◽  
Chemical Structures ◽  
Wide Range ◽  
Sulfur Containing ◽  
Sulfur Containing Compounds

The multiplicity of chemical structures of sulfur containing compounds, influenced in part by the element's several oxidation states, directly results in diverse modes of action for sulfur-containing natural products synthesized as secondary metabolites in plants. Sulfur-containing natural products constitute a formidable wall of defence against a wide range of pathogens and pests. Steady progress in the development of new technologies have advanced research in this area, helping to uncover the role of such important plant defence molecules like endogenously-released elemental sulphur, but also deepening current understanding of other better-studied compounds like the glucosinolates. As studies continue in this area, it is becoming increasingly evident that sulfur and sulfur compounds play far more important roles in plant defence than perhaps previously suspected.

scholarly journals Anaerobic Cysteine Degradation and Potential Metabolic Coordination in Salmonella enterica and Escherichia coli

2017 ◽  
Vol 199 (16) ◽  
Author(s):  
Melissa Loddeke ◽  
Barbara Schneider ◽  
Tamiko Oguri ◽  
Iti Mehta ◽  
Zhenyu Xuan ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Amino Acid ◽  
Salmonella Enterica ◽  
Acid Synthesis ◽  
Lower Growth ◽  
Amino Acid Synthesis ◽  
Content Type ◽  
E Coli ◽  
Sulfur Containing ◽  
Sulfur Containing Compounds

ABSTRACT Salmonella enterica has two CyuR-activated enzymes that degrade cysteine, i.e., the aerobic CdsH and an unidentified anaerobic enzyme; Escherichia coli has only the latter. To identify the anaerobic enzyme, transcript profiling was performed for E. coli without cyuR and with overexpressed cyuR. Thirty-seven genes showed at least 5-fold changes in expression, and the cyuPA (formerly yhaOM) operon showed the greatest difference. Homology suggested that CyuP and CyuA represent a cysteine transporter and an iron-sulfur-containing cysteine desulfidase, respectively. E. coli and S. enterica ΔcyuA mutants grown with cysteine generated substantially less sulfide and had lower growth yields. Oxygen affected the CyuR-dependent genes reciprocally; cyuP-lacZ expression was greater anaerobically, whereas cdsH-lacZ expression was greater aerobically. In E. coli and S. enterica, anaerobic cyuP expression required cyuR and cysteine and was induced by l-cysteine, d-cysteine, and a few sulfur-containing compounds. Loss of either CyuA or RidA, both of which contribute to cysteine degradation to pyruvate, increased cyuP-lacZ expression, which suggests that CyuA modulates intracellular cysteine concentrations. Phylogenetic analysis showed that CyuA homologs are present in obligate and facultative anaerobes, confirming an anaerobic function, and in archaeal methanogens and bacterial acetogens, suggesting an ancient origin. Our results show that CyuA is the major anaerobic cysteine-catabolizing enzyme in both E. coli and S. enterica, and it is proposed that anaerobic cysteine catabolism can contribute to coordination of sulfur assimilation and amino acid synthesis. IMPORTANCE Sulfur-containing compounds such as cysteine and sulfide are essential and reactive metabolites. Exogenous sulfur-containing compounds can alter the thiol landscape and intracellular redox reactions and are known to affect several cellular processes, including swarming motility, antibiotic sensitivity, and biofilm formation. Cysteine inhibits several enzymes of amino acid synthesis; therefore, increasing cysteine concentrations could increase the levels of the inhibited enzymes. This inhibition implies that control of intracellular cysteine levels, which is the immediate product of sulfide assimilation, can affect several pathways and coordinate metabolism. For these and other reasons, cysteine and sulfide concentrations must be controlled, and this work shows that cysteine catabolism contributes to this control.

N,N-Diethyl-p-phenylenediamine effectiveness in analysis of polysulfides and polythionates in water

2008 ◽  
Vol 5 (3) ◽  
pp. 226 ◽  
Author(s):  
Stephen Kariuki ◽  
Philippe Babady-Bila ◽  
Breanna Duquette
Keyword(s):  
Oxidation State ◽  
Environmental Samples ◽  
Environmental Pollutants ◽  
Spectrophotometric Analysis ◽  
Sulfur Compounds ◽  
Metallic Ions ◽  
Sulfur Species ◽  
Related Compounds ◽  
Sulfur Containing ◽  
Sulfur Containing Compounds

Environmental context. The importance of hydrogen sulfide as well as some of the reduced sulfur species such as polysulfides as environmental pollutants is a result of their toxicity, unpleasant odour, and their reactivity with metals and metallic ions found in various environmental samples. Although known to be popular, the effectiveness of N,N-diethyl-p-phenylenediamine and other related compounds in the spectrophotometric analysis of such sulfur compounds in water as well as in other environmental samples has not been fully investigated. Our results show that although the quantification of simple sulfides in the environmental samples may be easily accomplished spectrophotometrically by using N,N-diethyl-p-phenylenediamine, the level of difficulty in analysing such compounds may increase with their increasing sulfur chain. Abstract. The analysis of polysulfides, polythionates and other sulfur species likely to be found in poorly aerated environmental samples such as water is presented. In-depth spectrophotometric testing carried out using N,N-diethyl-p-phenylenediamine shows that the well known acidification-and-purge method is not sufficiently suitable for the analysis of polysulfides and other low oxidation-state sulfur compounds that contain a sulfur chain longer than two. Further, this study finds that the use of chromium(II) which acts as a reducing agent to the sulfur-containing compounds improves the spectrophotometric analysis of the polysulfides and polythionates in water, but only slightly. The extent of reduction of polysulfides and polythionates to sulfide by chromium appears dependent upon the oxidation state of sulfur as well as the chain length in the polysulfidic compounds.

scholarly journals Cysteine Metabolism-Related Genes and Bacterial Resistance to Potassium Tellurite

2007 ◽  
Vol 189 (24) ◽  
pp. 8953-8960 ◽  
Author(s):  
Derie E. Fuentes ◽  
Eugenia L. Fuentes ◽  
Miguel E. Castro ◽  
José M. Pérez ◽  
Manuel A. Araya ◽  
...  
Keyword(s):  
Small Molecules ◽  
Deleterious Effect ◽  
Culture Medium ◽  
Bacterial Resistance ◽  
Cell Tolerance ◽  
Geobacillus Stearothermophilus ◽  
Potassium Tellurite ◽  
Metabolic Genes ◽  
Sulfur Containing ◽  
Sulfur Containing Compounds

ABSTRACT Tellurite exerts a deleterious effect on a number of small molecules containing sulfur moieties that have a recognized role in cellular oxidative stress. Because cysteine is involved in the biosynthesis of glutathione and other sulfur-containing compounds, we investigated the expression of Geobacillus stearothermophilus V cysteine-related genes cobA, cysK, and iscS and Escherichia coli cysteine regulon genes under conditions that included the addition of K2TeO3 to the culture medium. Results showed that cell tolerance to tellurite correlates with the expression level of the cysteine metabolic genes and that these genes are up-regulated when tellurite is present in the growth medium.

scholarly journals Core RxLR Effectors in Phytopathogenic Oomycetes: A promising Way to Breeding for Durable Resistance in Plants?

2020 ◽  
Author(s):  
Jane Chepsergon ◽  
Thabiso Motaung ◽  
Lucy Moleleki
Keyword(s):  
Amino Acid ◽  
Genome Sequencing ◽  
Durable Resistance ◽  
Functional Characterization ◽  
Cellular Processes ◽  
Rxlr Effectors ◽  
High Level ◽  
Diverse Plant Species ◽  
Diverse Plant

Phytopathogenic oomycetes are known to infect a host plant successfully due to their ability to secrete a set of protein effectors. Of interest to many researchers are effectors with the N-terminal RxLR motif (Arginine-any amino acid-Leucine-Arginine). Owing to the genome sequencing, we can now comprehend the high level of diversity among oomycete effectors, and similarly, their conservation within and among species core RxLR effectors (CREs). Currently, there are a couple of putative CREs that have been identified in oomycetes. The functional characterization of these CREs proposes their virulence role with the potential of targeting central cellular processes that are conserved across diverse plant species. This could be harnessed in engineering plants for broad-spectrum and durable resistance.

Review of the Syntheses and Activities of Some Sulfur-Containing Drugs

2020 ◽  
Vol 17 (3) ◽  
pp. 192-210 ◽  
Author(s):  
Criscieli Taynara Barce Ferro ◽  
Beatriz Fuzinato dos Santos ◽  
Caren Daniele Galeano da Silva ◽  
George Brand ◽  
Beatriz Amaral Lopes da Silva ◽  
...  
Keyword(s):  
Chemical Compounds ◽  
Sulfur Compounds ◽  
Important Class ◽  
Materials Chemistry ◽  
Drug Candidates ◽  
Wide Range ◽  
Synthetic Routes ◽  
Pharmaceutical Properties ◽  
Sulfur Containing ◽  
Sulfur Containing Compounds

Background: Sulfur-containing compounds represent an important class of chemical compounds due to their wide range of biological and pharmaceutical properties. Moreover, sulfur-containing compounds may be applied in other fields, such as biological, organic, and materials chemistry. Several studies on the activities of sulfur compounds have already proven their anti-inflammatory properties and use to treat diseases, such as Alzheimer’s, Parkinson’s, and HIV. Moreover, examples of sulfur-containing compounds include dapsone, quetiapine, penicillin, probucol, and nelfinavir, which are important drugs with known activities. Objective: This review will focus on the synthesis and application of some sulfur-containing compounds used to treat several diseases, as well as promising new drug candidates. Results: Due to the variety of compounds containing C-S bonds, we have reviewed the different synthetic routes used toward the synthesis of sulfur-containing drugs and other compounds.

Distribution of Sulfur Forms in Low Temperature Pyrolysis of Coal

2012 ◽  
Vol 512-515 ◽  
pp. 834-837
Author(s):  
Qiu Xiang Yao ◽  
Mei Li Du ◽  
Shui Li Wang ◽  
Jing Liu ◽  
Jian Li Yang ◽  
...  
Keyword(s):  
Low Temperature ◽  
Coal Tar ◽  
Northwest China ◽  
Sulfur Compounds ◽  
Organic Sulfur ◽  
Total Sulfur ◽  
Low Temperature Pyrolysis ◽  
Sulfur Containing ◽  
Sulfur Containing Compounds ◽  
Typical Method

The distribution of sulfur forms in the products of low temperature pyrolysis of Carboniferous high sulfur coal from Northwest China was investigated. The typical method of Gray-King assay was used to carry out the low temperature pyrolysis experiments. GC-MS analysis was used to investigate the composition of sulfur compounds in the coal tar. The results show that sulfur mainly remained in the semi-coke and accounted for 80.97% of the total sulfur. Pyrites decomposed and transformed into sulfates and organic sulfur. 5 sulfur containing compounds were detected in the coal tar and they are dibenzothiophene, benzonaphthothiophene and their substituted homologs.

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