scholarly journals Regulatory Networks Governing Methionine Catabolism into Volatile Organic Sulfur-Containing Compounds in Clonostachys rosea

2018 ◽  
Vol 84 (22) ◽  
Author(s):  
Yang-Hua Xu ◽  
Kai-Zhi Jia ◽  
Ya-Jie Tang
Keyword(s):  
Catabolite Repression ◽  
Organic Sulfur ◽  
Nitrogen Catabolite Repression ◽  
Regulatory Pathway ◽  
Clonostachys Rosea ◽  
Ehrlich Pathway ◽  
Content Type ◽  
Volatile Organic ◽  
Sulfur Containing ◽  
Sulfur Containing Compounds

ABSTRACT Adaptation to environmental perturbations requires living systems to coordinately regulate signaling pathways, gene expression, and metabolism. To better understand the mechanisms underlying adaptation, the regulatory nodes within networks must be elucidated. Here, ARO8-2 (which encodes an aminotransferase), PDC (which encodes a decarboxylase), and STR3 (which encodes a demethiolase) were identified as key genes involved in the catabolism of methionine in the mycoparasitic fungus Clonostachys rosea, isolated from Tuber melanosporum ascocarps. Exogenous Met induced the transcription of ARO8-2 and PDC but repressed the transcription of STR3, which is controlled by the putative MSN2 and GLN3 binding sites responding to nitrogen catabolite repression. Met and its structural derivatives function as glutamine synthetase inhibitors, resulting in the downregulation of STR3 expression. The putative GLN3 binding site was necessary for STR3 downregulation. In Saccharomyces cerevisiae, Met and its structural derivatives also triggered downregulation of demethiolase gene expression. Altogether, the results indicated that exogenous Met triggered nitrogen catabolite repression, which stimulated the Ehrlich pathway and negatively regulated the demethiolation pathway via the methionine sulfoximine-responsive regulatory pathway. This finding revealed the regulatory nodes within the networks controlling the catabolism of Met into volatile organic sulfur-containing compounds, thereby enhancing our understanding of adaptation. IMPORTANCE Methionine shuttles organic nitrogen and plays a central role in nitrogen metabolism. Exogenous Met strongly induces the expression of ARO8-2 and PDC, represses the expression of STR3, and generates volatile organic sulfur-containing compounds via the Ehrlich and demethiolation pathways. In this study, we used genetic, bioinformatic, and metabolite-based analyses to confirm that transcriptional control of the aminotransferase gene ARO8-2, the decarboxylase gene PDC, and the demethiolase gene STR3 modulates Met catabolism into volatile organic sulfur-containing compounds. Importantly, we found that, in addition to the Ehrlich pathway, the demethiolation pathway was regulated by a nitrogen catabolite repression-sensitive regulatory pathway that controlled the transcription of genes required to catabolize poor nitrogen sources. This work significantly advances our understanding of nitrogen catabolite repression-sensitive transcriptional regulation of sulfur-containing amino acid catabolism and provides a basis for engineering Met catabolism pathways for the production of fuel and valuable flavor alcohols.

Composition and Structure of the Sulfur-Containing Compounds in the Extracts from the Chinese High-Organic-Sulfur Coals

2020 ◽  
Vol 34 (9) ◽  
pp. 10666-10675
Author(s):  
Yuegang Tang ◽  
Yewei Sun ◽  
Xiaoshuai Wang ◽  
Lulu Yan ◽  
Quan Shi ◽  
...  
Keyword(s):  
Organic Sulfur ◽  
Composition And Structure ◽  
Sulfur Containing ◽  
Sulfur Containing Compounds

Synthesis, characterization and environmental applications of nanocrystalline zeolites

2017 ◽  
Author(s):  
Vicki H. Grassian ◽  
Sarah C. Larsen
Keyword(s):  
Catalytic Reduction ◽  
Organic Phosphorus ◽  
Environmental Contaminants ◽  
Building Blocks ◽  
Environmental Applications ◽  
Environmental Catalysis ◽  
Hierarchical Zeolite ◽  
Volatile Organic ◽  
Sulfur Containing ◽  
Sulfur Containing Compounds

This article describes the synthesis, characterization and environmental applications of nanocrystalline zeolites. It begins by considering the use of nanocrystalline zeolites as building blocks in the preparation of hierarchical zeolite structures, followed by a discussion of the synthesis of silicalite-1 with systematically varied crystal sizes, along with the synthesis of nanocrystalline aluminosilicates, NaZSM-5 and NaY. It then looks at the various applications of nanozeolites and hierarchical zeolite structures for environmental catalysis, adsorption of volatile organic compounds and other environmental contaminants, selective catalytic reduction of nitrogen oxide, and decontamination of organic phosphorus and sulfur-containing compounds. It also examines the unique properties and reactivity of nanocrystalline zeolites and concludes by assessing their potential for future environmental applications.

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.

scholarly journals Global Expression Analysis of the Yeast Lachancea (Saccharomyces) kluyveri Reveals NewURCGenes Involved in Pyrimidine Catabolism

2013 ◽  
Vol 13 (1) ◽  
pp. 31-42 ◽  
Author(s):  
Anna Andersson Rasmussen ◽  
Dineshkumar Kandasamy ◽  
Halfdan Beck ◽  
Seth D. Crosby ◽  
Olof Björnberg ◽  
...  
Keyword(s):  
Expression Pattern ◽  
Catabolite Repression ◽  
Nitrogen Sources ◽  
Global Changes ◽  
Nitrogen Catabolite Repression ◽  
Content Type ◽  
Double Deletion ◽  
Pyrimidine Catabolism ◽  
Saccharomyces Kluyveri ◽  
Similar Expression Pattern

ABSTRACTPyrimidines are important nucleic acid precursors which are constantly synthesized, degraded, and rebuilt in the cell. Four degradation pathways, two of which are found in eukaryotes, have been described. One of them, theURCpathway, has been initially discovered in our laboratory in the yeastLachancea kluyveri. Here, we present the global changes in gene expression inL. kluyveriin response to different nitrogen sources, including uracil, uridine, dihydrouracil, and ammonia. The expression pattern of the knownURCgenes,URC1-6, helped to identify nine putative novelURCgenes with a similar expression pattern. The microarray analysis provided evidence that both theURCandPYDgenes are under nitrogen catabolite repression inL. kluyveriand are induced by uracil or dihydrouracil, respectively. We determined the function ofURC8, which was found to catalyze the reduction of malonate semialdehyde to 3-hydroxypropionate, the final degradation product of the pathway. The other eight genes studied were all putative permeases. Our analysis of double deletion strains showed that theL. kluyveriFui1p protein transported uridine, just like its homolog inSaccharomyces cerevisiae, but we demonstrated that is was not the only uridine transporter inL. kluyveri. We also showed that theL. kluyverihomologs ofDUR3andFUR4do not have the same function that they have inS. cerevisiae, where they transport urea and uracil, respectively. InL. kluyveri, both of these deletion strains grew normally on uracil and urea.

Corrosion of stainless steels in acid solutions with organic sulfur-containing compounds

1998 ◽  
Vol 41 (2) ◽  
pp. 321-333 ◽  
Author(s):  
X.L Cheng ◽  
H.Y Ma ◽  
S.H Chen ◽  
R Yu ◽  
X Chen ◽  
...  
Keyword(s):  
Stainless Steels ◽  
Organic Sulfur ◽  
Acid Solutions ◽  
Sulfur Containing ◽  
Sulfur Containing Compounds

scholarly journals Attraction of Adults of Cyclocephala lunulata and Cyclocephala barrerai (Coleoptera: Scarabaeoidea: Melolonthidae) towards Bacteria Volatiles Isolated from Their Genital Chambers

Molecules ◽  
2020 ◽  
Vol 25 (19) ◽  
pp. 4430
Author(s):  
Abraham Sanchez-Cruz ◽  
Norma Robledo ◽  
María Rosete-Enríquez ◽  
Angel A. Romero-López
Keyword(s):  
Solid Phase Microextraction ◽  
Solid Phase ◽  
Gas Chromatography Mass Spectrometry ◽  
Dynamic Headspace ◽  
Sex Attractants ◽  
Volatile Organic ◽  
The Relationship ◽  
Sulfur Containing ◽  
Antennal Responses ◽  
Sulfur Containing Compounds

In the study of the chemical communication of adults of the Melolonthidae family, bacteria have been observed in the epithelium of the genital chamber; possibly, bacteria are involved in the production of sex attractants in their hosts. Therefore, it is important to identify the volatile organic compounds from bacteria (VOCsB) released by these microorganisms and study the biological activity stimulated by VOBCs in adults of Melolonthidae. In this study, bacteria were isolated from the genital chamber of Cyclocephala lunulata and Cyclocephala barrerai, from which VOCsB were extracted using static headspace solid-phase microextraction (SHS-SPME) and dynamic headspace Super Q solid-phase extraction (DHS-SPE) and analyzed using gas chromatography-mass spectrometry. The effect of VOCsB on the hosts and conspecifics was evaluated utilizing an olfactometer and electroantennography (EAG). Two species of Enterobacteria were isolated from the genital chamber of each female species, and VOCsB derived from sulfur-containing compounds, alcohols, esters, and fatty acids were identified. An attraction response was observed in olfactometry studies, and antennal responses to VOCsB were confirmed in EAG bioassays. With these results, new perspectives on the relationship between these beetles and their bacteria emerge, in addition to establishing a basis for management programs in the future.

Analysis of aromatic hydrocarbon in medium- to high-sulfur coals from Fenxi, Shanxi Province

2018 ◽  
Vol 15 (6) ◽  
pp. 786-791 ◽  
Author(s):  
Yanli Yang ◽  
Qiaojing Zhao
Keyword(s):  
Gas Chromatography ◽  
Sulfur Compounds ◽  
Shanxi Province ◽  
Organic Sulfur ◽  
Gas Chromatography Mass Spectrometry ◽  
Content Type ◽  
Organic Sulfur Compounds ◽  
High Thermodynamic Stability ◽  
Sulfur Containing ◽  
Maturity Parameters

Purpose This study aims to investigate the compositional characteristics of aromatic hydrocarbons extracted from coals and to describe how the sulfur content influences the properties of coals and whether widely accepted maturity parameters are suitable for medium- to high-sulfur coal. Design/methodology/approach Four samples of medium- to high-sulfur coal were obtained from Fenxi, Shanxi Province, and studied using gas chromatography and gas chromatography–mass spectrometry (GC-MS). Findings The GC-MS results showed that there were five series of compounds were identified in the aromatic fractions: naphthalenes, phenanthrenes, oxygen-containing compounds, biphenyls and sulfur-containing compounds. The substituent group was mainly methyl. The content of dibenzothiophenes was high, which was attributed to their high thermodynamic stability. The presence of sulfur reduced the content of oxygen-containing compounds. A depositional environment that facilitated the formation of organic sulfur compounds led to a higher content of naphthalenes. Originality/value The development of methods for removing organic sulfur compounds would benefit from a study of their nature, which would be important for improving the use of coal.

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