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Enzymology of butyrate formation by Butyrivibrio fibrisolvens.

Miller, T L; Jenesel, S E
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /04/1979 EN
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Butyrivibrio fibrisolvens is a major butyrate-forming species in the bovine and ovine rumen. The enzymology of butyrate formation from pyruvate was investigated in cell-free extracts of B. fibrisolvens D1. Pyruvate owas oxidized to acetylcoenzyme A (CoA) in the presence of CoA.SH and benzyl viologen or flavin nucleotides. The bacterium uses thiolase, beta-hydroxybutyryl-CoA dehydrogenase, crotonase, and crotonyl-CoA reductase to form butyryl-CoA from acetyl-CoA. Reduction of acetoacetyl-CoA to beta-hydroxybutyryl-CoA was faster with NADH than with NADPH. Crotonyl-CoA was reduced to butyryl-CoA by NADH, but not by NADPH, only in the presence of flavin nucleotides. Reduction of flavin nucleotides by NADH was much slower than the flavin-dependent reduction of crotonyl-CoA. This indicates that flavoproteins rather than free flavin participated in the reduction of crotonyl-CoA. Butyryl-CoA was converted to butyrate by phosphate butyryl transferase and butyrate kinase.

Hill Reaction, Hydrogen Peroxide Scavenging, and Ascorbate Peroxidase Activity of Mesophyll and Bundle Sheath Chloroplasts of NADP-Malic Enzyme Type C4 Species 1

Nakano, Yoshiyuki; Edwards, Gerald E.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /09/1987 EN
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Intact mesophyll and bundle sheath chloroplasts wee isolated from the NADP-malic enzyme type C4 plants maize, sorghum (monocots), and Flaveria trinervia (dicot) using enzymic digestion and mechanical isolation techniques. Bundle sheath chloroplasts of this C4 subgroup tend to be agranal and were previously reported to be deficient in photosystem II activity. However, following injection of intact bundle sheath chloroplasts into hypotonic medium, thylakoids had high Hill reaction activity, similar to that of mesophyll chloroplasts with the Hill oxidants dichlorophenolindophenol, p-benzoquinone, and ferricyanide (approximately 200 to 300 micromoles O2 evolved per mg chlorophyll per hour). In comparison to that of mesophyll chloroplasts, the Hill reaction activity of bundle sheath chloroplasts of maize and sorghum was labile and lost activity during assay. Bundle sheath chloroplasts of maize also exhibited some capacity for 3-phosphoglycerate dependent O2 evolution (29 to 58 micromoles O2 evolved per milligram chlorophyll per hour). Both the mesophyll and bundle sheath chloroplasts were equally effective in light dependent scavenging of hydrogen peroxide. The results suggest that both chloroplast types have noncyclic electron transport and the enzymology to reduce hydrogen peroxide to water. The activities of ascorbate peroxidase from these chloroplast types was consistent with their capacity to scavenge hydrogen peroxide.

Stress Responses in Alfalfa (Medicago sativa L.): I. Induction of Phenylpropanoid Biosynthesis and Hydrolytic Enzymes in Elicitor-Treated Cell Suspension Cultures

Dalkin, Karen; Edwards, Robert; Edington, Brent; Dixon, Richard A.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /02/1990 EN
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246.93043%
Alfalfa (Medicago sativa L.) cell suspension cultures accumulated high concentrations of the pterocarpan phytoalexin medicarpin, reaching a maximum within 24 hours after exposure to an elicitor preparation from cell walls of the phytopathogenic fungus Colletotrichum lindemuthianum. This was preceded by increases in the extractable activities of the isoflavonoid biosynthetic enzymes l-phenylalanine ammonia-lyase, cinnamic acid 4-hydroxylase, 4-coumarate coenzyme A-ligase, chalcone synthase, chalcone isomerase, and isoflavone O-methyltransferase. Pectic polysaccharides were weak elicitors of phenylalanine ammonia-lyase activity but did not induce medicarpin accumulation, whereas reduced glutathione was totally inactive as an elicitor in this system. The fungal cell wall extract was a weak elicitor of the lignin biosynthetic enzymes, caffeic acid O-methyltransferase and coniferyl alcohol dehydrogenase, but did not induce appreciable increases in the activities of the hydrolytic enzymes chitinase and 1,3-β-d-glucanase. The results are discussed in relation to the activation of isoflavonoid biosynthesis in other legumes and the development of the alfalfa cell culture system as a model for studying the enzymology and molecular biology of plant defense expression.

Cyanogenesis in Plants 1

Poulton, Jonathan E.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /10/1990 EN
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246.93043%
Several thousand plant species, including many economically important food plants, synthesize cyanogenic glycosides and cyanolipids. Upon tissue disruption, these natural products are hydrolyzed liberating the respiratory poison hydrogen cyanide. This phenomenon of cyanogenesis accounts for numerous cases of acute and chronic cyanide poisoning of animals including man. This article reviews information gathered during the past decade about the enzymology and molecular biology of cyanogenesis in higher plants. How compartmentation normally prevents the large-scale, suicidal release of HCN within the intact plant is discussed. A renewed interest in the physiology of these cyanogenic compounds has revealed that, in addition to providing protection for some species against herbivory, they may also serve as storage forms for reduced nitrogen.

Enzymology of the Reduction of Hydroxypyruvate and Glyoxylate in a Mutant of Barley Lacking Peroxisomal Hydroxypyruvate Reductase 1

Kleczkowski, Leszek A.; Edwards, Gerald E.; Blackwell, Ray D.; Lea, Peter J.; Givan, Curtis V.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /10/1990 EN
Relevância na Pesquisa
246.93043%
The use of LaPr 88/29 mutant of barley (Hordeum vulgare), which lacks NADH-preferring hydroxypyruvate reductase (HPR-1), allowed for an unequivocal demonstration of at least two related NADPH-preferring reductases in this species: HPR-2, reactive with both hydroxypyruvate and glyoxylate, and the glyoxylate specific reductase (GR-1). Antibodies against spinach HPR-1 recognized barley HPR-1 and partially reacted with barley HPR-2, but not GR-1, as demonstrated by Western immunoblotting and immunoprecipitation of proteins from crude leaf extracts. The mutant was deficient in HPR-1 protein. In partially purified preparations, the activities of HPR-1, HPR-2, and GR-1 could be differentiated by substrate kinetics and/or inhibition studies. Apparent Km values of HPR-2 for hydroxypyruvate and glyoxylate were 0.7 and 1.1 millimolar, respectively, while the Km of GR-1 for glyoxylate was 0.07 millimolar. The Km values of HPR-1, measured in wild type, for hydroxypyruvate and glyoxylate were 0.12 and 20 millimolar, respectively. Tartronate and P-hydroxypyruvate acted as selective uncompetitive inhibitors of HPR-2 (Ki values of 0.3 and 0.4 millimolar, respectively), while acetohydroxamate selectively inhibited GR-1 activity. Nonspecific contributions of HPR-1 reactions in assays of HPR-2 and GR-1 activities were quantified by a direct comparison of rates in preparations from wild-type and LaPr 88/29 plants. The data are evaluated with respect to previous reports on plant HPR and GR activities and with respect to optimal assay procedures for individual HPR-1...

Secreting Glandular Trichomes: More than Just Hairs

Wagner, George J.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /07/1991 EN
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246.93043%
Secreting glandular plant trichome types which accumulate large quantities of metabolic products in the space between their gland cell walls and cuticle permit the plant to amass secretions in a compartment that is virtually outside the plant body. These structures not only accumulate and store what are often phytotoxic oils but they position these compounds as an apparent first line of defense at the surface of the plant. Recent advances in methods for isolation and study of trichome glands have allowed more precise analysis of gland cell metabolism and enzymology. Isolation of mutants with altered trichome phenotypes provides new systems for probing the genetic basis of trichome development. These advances and their continuation can pave the way for future attempts at modification of trichome secretion. The biochemical capability of glandular secreting trichomes and the potential for its future manipulation to exploit this external storage compartment is the focus of this review.

Microbial metabolism of aromatic nitriles. Enzymology of C–N cleavage by Nocardia sp. (Rhodochrous group) N.C.I.B. 11216

Harper, David B.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 01/08/1977 EN
Relevância na Pesquisa
246.93043%
1. An organism utilizing benzonitrile as sole carbon and nitrogen source was isolated by the enrichment-culture technique and identified as a Nocardia sp. of the rhodochrous group. 2. Respiration studies indicate that nitrile degradation proceeds through benzoic acid and catechol. 3. Cell-free extracts of benzonitrile-grown cells contain an enzyme that catalyses the conversion of benzonitrile directly into benzoic acid without intermediate formation of benzamide. 4. This nitrilase enzyme was purified by DEAE-cellulose chromatography and gel filtration on Sephadex G-100 in the presence and absence of substrate. The purity of the enzyme was confirmed by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis and isoelectric focusing on polyacrylamide gel. 5. The enzyme shows a time-dependent substrate-activation process in which the substrate catalyses the association of inactive subunits of mol.wt. 45000 to form the polymeric 12-unit active enzyme of mol.wt. 560000. The time required for complete association is highly dependent on the concentration of the enzyme, temperature and pH. 6. The associated enzyme has a pH optimum of 8.0 and Km with benzonitrile as substrate of 4mm. The activation energy of the reaction as deduced from the Arrhenius plot is 51.8kJ/mol. 7. Enzyme activity is inhibited by thiol-specific reagents and several metal ions. 8. Studies with different substrates indicate that the nitrilase is specific for nitrile groups directly attached to the benzene ring. Various substituents in the ring are compatible with activity...

The enzymology of short-chain fatty acyl-coenzyme A synthetase from seeds of Pinus radiata. Kinetic studies and a proposed reaction mechanism

Young, Owen A.; Anderson, John W.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /03/1974 EN
Relevância na Pesquisa
246.93043%
1. Short-chain fatty acyl-CoA synthetase from seeds of Pinus radiata was examined by acetate- and propionate-dependent PPi–ATP exchange. Reaction mixtures came to equilibrium almost instantly as judged by rates of exchange and analysis of an incubation mixture. 2. The activity of the enzyme was correlated with the concentration of MgP2O72− but not with the concentration of Mg2+, as judged by PPi–ATP exchange and fatty acyl AMP-dependent synthesis of ATP in the presence of PPi. In PPi–ATP exchange assays, no clear relationship between activity and any single species of ATP was apparent. 3. High concentrations of fatty acid inhibited PPi–ATP exchange. PPi–dATP exchange was less than PPi–ATP exchange at low concentrations of fatty acid, but at higher concentrations PPi–dATP exchange exceeded PPi–ATP exchange. The rate of synthesis of fatty acyl-CoA in the presence of dATP was less than with ATP. 4. ATP and propionate inhibited the synthesis of ATP from propionyl-AMP and PPi. The inhibition by ATP was competitive with respect to propionyl-AMP and non-competitive with respect to PPi. The inhibition by propionate was non-competitive with respect to propionyl-AMP and PPi. 5. AMP was a competitive inhibitor of propionyl-AMP-dependent synthesis of ATP and competitively inhibited propionate-dependent PPi–ATP exchange when ATP was the variable substrate. 6. It was concluded that the first partial reaction catalysed by the enzyme is ordered; ATP is the first substrate to react with the enzyme and PPi is probably the only product released.

The enzymology of adenosine triphosphate sulphurylase from spinach leaf tissue. Kinetic studies and a proposed reaction mechanism

Shaw, W. H.; Anderson, J. W.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /04/1974 EN
Relevância na Pesquisa
246.93043%
1. Sulphate-dependent PPi–ATP exchange, catalysed by purified spinach leaf ATP sulphurylase, was correlated with the concentration of MgATP2− and MgP2O72−; ATP sulphurylase activity was not correlated with the concentration of free Mg2+. 2. Sulphate-dependent PPi–ATP exchange was independent of PPi concentration, but dependent on the concentration of ATP and sulphate. The rate of sulphate-dependent PPi–ATP exchange was quantitatively defined by the rate equation applicable to the initial rate of a bireactant sequential mechanism under steady-state conditions. 3. Chlorate, nitrate and ADP inhibited the exchange reaction. The inhibition by chlorate and nitrate was uncompetitive with respect to ATP and competitive with respect to sulphate. The inhibition by ADP was competitive with respect to ATP and non-competitive with respect to sulphate. 4. ATP sulphurylase catalysed the synthesis of [32P]ATP from [32P]PPi and adenosine 5′-sulphatophosphate in the absence of sulphate; some properties of the reaction are described. Enzyme activity was dependent on the concentration of PPi and adenosine 5′-sulphatophosphate. 5. The synthesis of ATP from PPi and adenosine 5′-sulphatophosphate was inhibited by sulphate and ATP. The inhibition by sulphate was non-competitive with respect to PPi and adenosine 5′-sulphatophosphate; the inhibition by ATP was competitive with respect to adenosine 5′-sulphatophosphate and non-competitive with respect to PPi. It was concluded that the reaction catalysed by spinach leaf ATP sulphurylase was ordered; expressing the order in the forward direction...

Comparative enzymology of the adenosine triphosphate sulphurylases from leaf tissue of selenium-accumulator and non-accumulator plants

Shaw, W. H.; Anderson, J. W.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /04/1974 EN
Relevância na Pesquisa
246.93043%
1. ATP sulphurylases were partially purified (20–40-fold) from leaf tissue of Astragalus bisulcatus, Astragalus racemosus (selenium-accumulator species) and Astragalus hamosus and Astragalus sinicus (non-accumulator species). Activity was measured by sulphate-dependent PPi–ATP exchange. The enzymes were separated from pyrophosphatase and adenosine triphosphatase activities. The properties of the Astragalus ATP sulphurylases were similar to the spinach enzyme. 2. The ATP sulphurylases from both selenium-accumulator and non-accumulator species catalysed selenate-dependent PPi–ATP exchange; selenate competed with sulphate. The ratio of V(selenate)/V(sulphate) and Km(selenate)/Km(sulphate) was approximately the same for the enzyme from each species. 3. Sulphate-dependent PPi–ATP exchange was inhibited by ADP, chlorate and nitrate. The kinetics of the inhibition for each enzyme were consistent with an ordered reaction mechanism, in which ATP is the first substrate to react with the enzyme and PPi is the first product released. 4. Synthesis of adenosine 5′-[35S]sulphatophosphate from [35S]sulphate was demonstrated by coupling the Astragalus ATP sulphurylases with Mg2+-dependent pyrophosphatase; the reaction was inhibited by selenate. An analogous reaction using [75Se]selenate as substrate could not be demonstrated.

Fungal degradation of aromatic nitriles. Enzymology of C–N cleavage by Fusarium solani

Harper, David B.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 01/12/1977 EN
Relevância na Pesquisa
246.93043%
1. A strain of the fungus Fusarium solani able to use benzonitrile as sole source of carbon and nitrogen was isolated by elective culture. 2. Respiration studies indicate that the nitrile, after degradation to benzoate, is catabolized via catechol or alternatively via p-hydroxybenzoate and 3,4-dihydroxybenzoate. 3. Cell-free extracts of benzonitrile-grown cells contain an enzyme mediating the conversion of benzonitrile into benzoate and ammonia. 4. The nitrilase enzyme was purified by DEAE-cellulose chromatography, (NH4)2SO4 precipitation and gel filtration on Sephadex G-200. The homogeneity of the purified enzyme preparation was confirmed by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis and isoelectric focusing on polyacrylamide gel. 5. The enzyme showed a broad pH optimum between pH7.8 and 9.1 and a Km with benzonitrile as substrate of 0.039mm. The activation energy of the reaction deduced from an Arrhenius plot was 48.4kJ/mol. 6. The enzyme was susceptible to inhibition by thiol-specific reagents and certain heavy metal ions. 7. Gel filtration gave a value of 620000 for the molecular weight of the intact enzyme. Sodium dodecyl sulphate/polyacrylamide-gel electrophoresis demonstrated that the enzyme was composed of eight subunits of mol.wt. 76000. 8. Rates of enzymic attack on various substrates indicated that the nitrilase has a fairly broad specificity and that the fungus probably plays an important role in the biodegradation of certain nitrilic herbicides in the environment.

Early organogenesis of human small intestine: scanning electron microscopy and brush border enzymology.

Lacroix, B; Kedinger, M; Simon-Assmann, P; Haffen, K
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /09/1984 EN
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246.93043%
Human small bowel early organogenesis was studied by scanning electron microscopy and found to be correlated to brush border enzymology. The appearance of the brush border enzymes sucrase, lactase, and aminopeptidase (measured in a purified apical membrane fraction) coincides with the first outgrowth of villi (eight weeks). Alkaline phosphatase was detected at seven weeks. The content of these enzymes furthermore increased up to the 14th week when both sucrase and aminopeptidase activities were comparable with adult values.

An Embarrassment of Riches: The Enzymology of RNA Modification

Iwata-Reuyl, Dirk
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
246.93043%
The maturation of transfer RNA (tRNA) involves extensive chemical modification of the constituent nucleosides, resulting in the formation of structurally diverse nucleosides. Many of the pathways to these modified nucleosides are characterized by chemically complex transformations, some of which are unprecedented in other areas of biology. To illustrate the scope of the field, recent progress in understanding the enzymology leading to the formation of 2 distinct classes of modified nucleosides are reviewed, the thiouridines and queuosine, a 7-deazaguanosine. In particular, recent data validating the involvement of several proposed intermediates in the formation of thiouridines are discussed, including 2 key enzyme intermediates and the activated tRNA intermediate. The discovery and mechanistic characterization of a new enzyme activity in the queuosine pathway is discussed.

Enzymology takes a quantum leap forward

Sutcliffe, Michael J.; Scrutton, Nigel S.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 15/01/2000 EN
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Enzymes are biological molecules that accelerate chemical reactions. They are central to the existence of life. Since the discovery of enzymes just over a century ago, we have witnessed an explosion in our understanding of enzyme catalysis, leading to a more detailed appreciation of how they work. A key breakthrough came from understanding how enzymes surmount the potential-energy barrier that separates reactants from products. The genetic engineering revolution has provided tools for dissecting enzyme structure and enabling design of novel function. Despite the huge efforts to redesign enzyme molecules for specific applications, progress in this area has been generally disappointing. This stems from our limited understanding of the subtleties by which enzymes enhance reaction rates. Based on current dogma, the vast majority of studies have concentrated on understanding how enzymes facilitate passage of the reaction over a static potential-energy barrier. However, recent studies have revealed that passage through, rather than over, the barrier can occur. These studies reveal that quantum mechanical phenomena, driven by protein dynamics, can play a pivotal role in enzyme action. The new millennium will witness a flurry of activity directed at understanding the role of quantum mechanics and protein motion in enzyme action. We discuss these new developments and how they will guide enzymology into the new millennium.

STRUCTURAL ENZYMOLOGY OF POLYKETIDE SYNTHASES

Tsai, Shiou-Chuan (Sheryl); Ames, Brian Douglas
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em //2009 EN
Relevância na Pesquisa
246.93043%
This chapter describes structural and associated enzymological studies of polyketide synthases, including isolated single domains and multidomain fragments. The sequence–structure–function relationship of polyketide biosynthesis, compared with homologous fatty acid synthesis, is discussed in detail. Structural enzymology sheds light on sequence and structural motifs that are important for the precise timing, substrate recognition, enzyme catalysis, and protein–protein interactions leading to the extraordinary structural diversity of naturally occurring polyketides.

The enzymology of mitochondrial fatty acid beta-oxidation and its application to follow-up analysis of positive neonatal screening results

Wanders, Ronald J. A.; Ruiter, Jos P. N.; IJlst, Lodewijk; Waterham, Hans R.; Houten, Sander M.
Fonte: Springer Netherlands Publicador: Springer Netherlands
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
246.93043%
Oxidation of fatty acids in mitochondria is a key physiological process in higher eukaryotes including humans. The importance of the mitochondrial beta-oxidation system in humans is exemplified by the existence of a group of genetic diseases in man caused by an impairment in the mitochondrial oxidation of fatty acids. Identification of patients with a defect in mitochondrial beta-oxidation has long remained notoriously difficult, but the introduction of tandem-mass spectrometry in laboratories for genetic metabolic diseases has revolutionalized the field by allowing the rapid and sensitive analysis of acylcarnitines. Equally important is that much progress has been made with respect to the development of specific enzyme assays to identify the enzyme defect in patients subsequently followed by genetic analysis. In this review, we will describe the current state of knowledge in the field of fatty acid oxidation enzymology and its application to the follow-up analysis of positive neonatal screening results.

Enzymology of the Wood–Ljungdahl Pathway of Acetogenesis

Ragsdale, Stephen W.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /03/2008 EN
Relevância na Pesquisa
246.93043%
The biochemistry of acetogenesis is reviewed. The microbes that catalyze the reactions that are central to acetogenesis are described and the focus is on the enzymology of the process. These microbes play a key role in the global carbon cycle, producing over 10 trillion kilograms of acetic acid annually. Acetogens have the ability to anaerobically convert carbon dioxide and CO into acetyl-CoA by the Wood–Ljungdahl pathway, which is linked to energy conservation. They also can convert the six carbons of glucose stoichiometrically into 3 mol of acetate using this pathway. Acetogens and other anaerobic microbes (e.g., sulfate reducers and methanogens) use the Wood–Ljungdahl pathway for cell carbon synthesis. Important enzymes in this pathway that are covered in this review are pyruvate ferredoxin oxidoreductase, CO dehydrogenase/acetyl-CoA synthase, a corrinoid iron-sulfur protein, a methyltransferase, and the enzymes involved in the conversion of carbon dioxide to methyl-tetrahydrofolate.

Enzymology of the branched-chain amino acid oxidation disorders: the valine pathway

Wanders, Ronald J. A.; Duran, Marinus; Loupatty, Ference J.
Fonte: Springer Netherlands Publicador: Springer Netherlands
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
246.93043%
Valine is one of the three branched-chain amino acids which undergoes oxidation within mitochondria. In this paper, we describe the current state of knowledge with respect to the enzymology of the valine oxidation pathway and the different disorders affecting oxidation.

Bacterial Diterpene Synthases: New Opportunities for Mechanistic Enzymology and Engineered Biosynthesis

Smanski, Michael J.; Peterson, Ryan M.; Huang, Sheng-Xiong; Shen, Ben
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
246.93043%
Diterpenoid biosynthesis has been extensively studied in plants and fungi, yet cloning and engineering diterpenoid pathways in these organisms remain challenging. Bacteria are emerging as prolific producers of diterpenoid natural products, and bacterial diterpene synthases are poised to make significant contributions to our understanding of terpenoid biosynthesis. Here we will first survey diterpenoid natural products of bacterial origin and briefly review their biosynthesis with emphasis on diterpene synthases (DTSs) that channel geranylgeranyl diphosphate to various diterpenoid scaffolds. We will then highlight differences of DTSs of bacterial and higher organism origins and discuss the challenges in discovering novel bacterial DTSs. We will conclude by discussing new opportunities for DTS mechanistic enzymology and applications of bacterial DTS in biocatalysis and metabolic pathway engineering.

Integrating genomics, transcriptomics, proteomics, and metabolomics into environmental enzymology: the next frontier or fool's gold?

Matthew D. Wallenstein
Fonte: Nature Preceedings Publicador: Nature Preceedings
Tipo: Conferência ou Objeto de Conferência
Relevância na Pesquisa
257.7605%
Extracellular enzymes are widely measured as indices of microbial activity, resource allocation, and substrate availability. However, interpretation of enzyme activities is hampered by a limited understanding of controls on enzyme production, turnover, and in-situ activity. In part, this is the consequence of methodological limitations, which require artificial substrates and are conducted under conditions that differ from in situ conditions. Recently, new tools have emerged that have potential to provide new insights into microbial enzymology. Will these methods open a new frontier in enzymology research, or will they only result in the discovery of fool’s gold? I will highlight how genomic, transcriptomic, proteomic, and metabolomic tools might be used to gain new insights into the controls on enzyme production, turnover, and in-situ activity. I will also discuss the potential for significant advancements even without the use of emerging tools. Each of these techniques offers the potential to provide new pieces to the puzzle of environmental enzymology, but progress is most likely through a multi-faceted approach.