Genomes and Genes
Summary: Five-carbon saturated hydrocarbon group of the methane series. Include isomers and derivatives.
- Takeno S, Bamba T, Nakazawa Y, Fukusaki E, Okazawa A, Kobayashi A. Quantification of trans-1,4-polyisoprene in Eucommia ulmoides by fourier transform infrared spectroscopy and pyrolysis-gas chromatography/mass spectrometry. J Biosci Bioeng. 2008;105:355-9 pubmed publisher..We successfully applied the extraction/quantification method for study of seasonal changes in EU-rubber content and molecular weight distribution...
- Behnke K, Ehlting B, Teuber M, Bauerfeind M, Louis S, Hansch R, et al. Transgenic, non-isoprene emitting poplars don't like it hot. Plant J. 2007;51:485-99 pubmed..In conclusion, using a molecular genetic approach, we show that down-regulation of isoprene emission affects thermotolerance of photosynthesis and induces increased energy dissipation by NPQ pathways. ..
- Martins G, Ferreira Rodrigues A, Rodrigues F, de Souza G, Mason N, Eden S, et al. Valence shell electronic spectroscopy of isoprene studied by theoretical calculations and by electron scattering, photoelectron, and absolute photoabsorption measurements. Phys Chem Chem Phys. 2009;11:11219-31 pubmed publisher..The calculations are compared with the He(i) photoelectron spectrum (8 to 17 eV) and new vibrational structure is observed in the first photoelectron band. ..
- Loreto F, Centritto M, Barta C, Calfapietra C, Fares S, Monson R. The relationship between isoprene emission rate and dark respiration rate in white poplar (Populus alba L.) leaves. Plant Cell Environ. 2007;30:662-9 pubmed
- Kushch I, Arendacká B, Stolc S, Mochalski P, Filipiak W, Schwarz K, et al. Breath isoprene--aspects of normal physiology related to age, gender and cholesterol profile as determined in a proton transfer reaction mass spectrometry study. Clin Chem Lab Med. 2008;46:1011-8 pubmed publisher..Further investigations are necessary to clarify the relation between isoprene concentrations in exhaled breath and cholesterol levels and synthesis rates in blood. ..
- Loivamäki M, Gilmer F, Fischbach R, Sörgel C, Bachl A, Walter A, et al. Arabidopsis, a model to study biological functions of isoprene emission?. Plant Physiol. 2007;144:1066-78 pubmed..Hence, this study demonstrates the enormous potential but also the pitfalls of transgenic Arabidopsis (or other nonnatural isoprenoid emitters) in studying isoprene biosynthesis and its biological function(s). ..
- Velikova V, Várkonyi Z, Szabó M, Maslenkova L, Nogues I, Kovacs L, et al. Increased thermostability of thylakoid membranes in isoprene-emitting leaves probed with three biophysical techniques. Plant Physiol. 2011;157:905-16 pubmed publisher..These results contribute to our understanding of isoprene mechanism of action in plant protection against environmental stresses. ..
- Vickers C, Possell M, Nicholas Hewitt C, Mullineaux P. Genetic structure and regulation of isoprene synthase in Poplar (Populus spp.). Plant Mol Biol. 2010;73:547-58 pubmed publisher..No thylakoid isoforms could be identified in Populus alba or in Salix babylonica. Together, these data show that control of isoprene emission at the genetic level is far more complicated than previously assumed. ..
- Lindberg P, Park S, Melis A. Engineering a platform for photosynthetic isoprene production in cyanobacteria, using Synechocystis as the model organism. Metab Eng. 2010;12:70-9 pubmed publisher..Results showed that oxygenic photosynthesis can be re-directed to generate useful small volatile hydrocarbons, while consuming CO(2), without a prior requirement for the harvesting, dewatering and processing of the respective biomass. ..
- Crohns M, Saarelainen S, Laitinen J, Peltonen K, Alho H, Kellokumpu Lehtinen P. Exhaled pentane as a possible marker for survival and lipid peroxidation during radiotherapy for lung cancer--a pilot study. Free Radic Res. 2009;43:965-74 pubmed publisher..003). Elevated exhaled pentane levels before RT may be due to the lipid peroxidation burden associated with cancer. The decrease of lipid peroxidation markers during RT may be attributable to enhanced antioxidant defense mechanisms. ..
- Fu P, Kawamura K, Chen J, Barrie L. Isoprene, monoterpene, and sesquiterpene oxidation products in the high Arctic aerosols during late winter to early summer. Environ Sci Technol. 2009;43:4022-8 pubmed..This study demonstrates that photochemical oxidation of BVOCs also contributes to the formation of OC and WSOC in the Arctic atmosphere during late winter to early summer. ..
- Kourtchev I, Warnke J, Maenhaut W, Hoffmann T, Claeys M. Polar organic marker compounds in PM2.5 aerosol from a mixed forest site in western Germany. Chemosphere. 2008;73:1308-14 pubmed publisher..In addition, the occurrence of levoglucosan and pyrogallol indicates that the site is affected by biomass combustion. Their median concentrations were 30 and 8.9 ng m(-3), respectively...
- Laothawornkitkul J, Paul N, Vickers C, Possell M, Taylor J, Mullineaux P, et al. Isoprene emissions influence herbivore feeding decisions. Plant Cell Environ. 2008;31:1410-5 pubmed publisher..Both in vivo and in vitro experiments showed that isoprene can activate feeding avoidance behaviour in this system with a dose-response effect on caterpillar behaviour and an isoprene emission threshold level of <6 nmol m(-2) s(-1). ..
- Xue J, Ahring B. Enhancing isoprene production by genetic modification of the 1-deoxy-d-xylulose-5-phosphate pathway in Bacillus subtilis. Appl Environ Microbiol. 2011;77:2399-405 pubmed publisher..In addition, induction and repression effects are independent of SigB, which is the general stress-responsive alternative sigma factor of Gram-positive bacteria. ..
- Teuber M, Zimmer I, Kreuzwieser J, Ache P, Polle A, Rennenberg H, et al. VOC emissions of Grey poplar leaves as affected by salt stress and different N sources. Plant Biol (Stuttg). 2008;10:86-96 pubmed publisher..6 microl x l(-1). Why poplar leaves maintain VOC biosynthesis and emission under salt stress conditions, despite impaired photosynthetic CO(2) fixation, is discussed. ..
- Sharkey T, Wiberley A, Donohue A. Isoprene emission from plants: why and how. Ann Bot. 2008;101:5-18 pubmed..Understanding the regulation of isoprene emission is advancing rapidly now that the pathway that provides the substrate is known. ..
- Behnke K, Loivamäki M, Zimmer I, Rennenberg H, Schnitzler J, Louis S. Isoprene emission protects photosynthesis in sunfleck exposed Grey poplar. Photosynth Res. 2010;104:5-17 pubmed publisher..Thus, there is evidence for an adjustment of the antioxidative system in the non-isoprene emitting poplars even under normal growth conditions. ..
- Rohmer M. From molecular fossils of bacterial hopanoids to the formation of isoprene units: discovery and elucidation of the methylerythritol phosphate pathway. Lipids. 2008;43:1095-107 pubmed publisher..It is present in most bacteria and in the plastids of all organisms belonging to phototrophic phyla. The key steps of the discovery and elucidation of this metabolic route are presented in this review...
- Ghirardo A, Zimmer I, Bruggemann N, Schnitzler J. Analysis of 1-deoxy-D-xylulose 5-phosphate synthase activity in Grey poplar leaves using isotope ratio mass spectrometry. Phytochemistry. 2010;71:918-22 pubmed publisher..Consequently, we found lower DXS activity in non-isoprene-emitting lines of poplar than in emitting plants as indicator of a lower demand of metabolic flux within the MEP pathway. ..
- Siwko M, Marrink S, de Vries A, Kozubek A, Schoot Uiterkamp A, Mark A. Does isoprene protect plant membranes from thermal shock? A molecular dynamics study. Biochim Biophys Acta. 2007;1768:198-206 pubmed..Furthermore it provides a clear mechanistic picture as to why plants specifically utilize isoprene for this purpose. ..
- Sasaki K, Saito T, Lämsä M, Oksman Caldentey K, Suzuki M, Ohyama K, et al. Plants utilize isoprene emission as a thermotolerance mechanism. Plant Cell Physiol. 2007;48:1254-62 pubmed..In contrast, neither strong light nor drought treatments showed an apparent difference. These data suggest that isoprene emission plays a crucial role in a heat protection mechanism in plants. ..
- Brilli F, Barta C, Fortunati A, Lerdau M, Loreto F, Centritto M. Response of isoprene emission and carbon metabolism to drought in white poplar (Populus alba) saplings. New Phytol. 2007;175:244-54 pubmed..Isoprene emission was likely controlled at the posttranscriptional level under severe drought. ..
- Julsing M, Rijpkema M, Woerdenbag H, Quax W, Kayser O. Functional analysis of genes involved in the biosynthesis of isoprene in Bacillus subtilis. Appl Microbiol Biotechnol. 2007;75:1377-84 pubmed..subtilis. ..
- Loivamäki M, Louis S, Cinege G, Zimmer I, Fischbach R, Schnitzler J. Circadian rhythms of isoprene biosynthesis in grey poplar leaves. Plant Physiol. 2007;143:540-51 pubmed
- Meskhidze N, Nenes A. Phytoplankton and cloudiness in the Southern Ocean. Science. 2006;314:1419-23 pubmed..Model simulations support this hypothesis, indicating that 100% of the observed changes in cloud properties can be attributed to the isoprene secondary organic aerosol. ..
- Miller B, Oschinski C, Zimmer W. First isolation of an isoprene synthase gene from poplar and successful expression of the gene in Escherichia coli. Planta. 2001;213:483-7 pubmed..Omitting the part of the gene that putatively encoded the signal peptide necessary for transport into the chloroplast led to an enhanced rate of isoprene formation by the recombinant protein...
- Sivy T, Shirk M, Fall R. Isoprene synthase activity parallels fluctuations of isoprene release during growth of Bacillus subtilis. Biochem Biophys Res Commun. 2002;294:71-5 pubmed..These results suggest that isoprene synthesis is highly regulated in B. subtilis and further research in this model system may shed light on the role of isoprene formation in biological systems. ..
- Affek H, Yakir D. Protection by isoprene against singlet oxygen in leaves. Plant Physiol. 2002;129:269-77 pubmed..77 to 0.27). The internal isoprene concentrations used in this study and possible rate of 1O2 production in leaves indicate that the protective effects observed should be beneficial also under natural conditions...
- Schubert J, Miekisch W, Birken T, Geiger K, Nöldge Schomburg G. Impact of inspired substance concentrations on the results of breath analysis in mechanically ventilated patients. Biomarkers. 2005;10:138-52 pubmed..Hence, substances having inspired concentrations>5% of expired concentrations should not be used as breath markers in these patients without knowledge of concentrations in blood and breath. ..
- Velikova V, Pinelli P, Pasqualini S, Reale L, Ferranti F, Loreto F. Isoprene decreases the concentration of nitric oxide in leaves exposed to elevated ozone. New Phytol. 2005;166:419-25 pubmed
- Wolfertz M, Sharkey T, Boland W, Kuhnemann F. Rapid regulation of the methylerythritol 4-phosphate pathway during isoprene synthesis. Plant Physiol. 2004;135:1939-45 pubmed..The results confirm that isoprene synthase has a K(m) 10- to 100-fold higher for its allylic diphosphate substrate than related monoterpene synthases for geranyl diphosphate. ..
- Wilkins C, Clausen P, Wolkoff P, Larsen S, Hammer M, Larsen K, et al. Formation of strong airway irritants in mixtures of isoprene/ozone and isoprene/ozone/nitrogen dioxide. Environ Health Perspect. 2001;109:937-41 pubmed..This suggests that one or more strong airway irritants were formed. It is thus possible that oxidation reactions of common unsaturated compounds may be relevant for indoor air quality. ..
- Kuzuyama T. Mevalonate and nonmevalonate pathways for the biosynthesis of isoprene units. Biosci Biotechnol Biochem. 2002;66:1619-27 pubmed..chem.qmw.ac.uk/iubmb/enzyme/reaction/terp/nonMVA.html. ..
- Loreto F, Mannozzi M, Maris C, Nascetti P, Ferranti F, Pasqualini S. Ozone quenching properties of isoprene and its antioxidant role in leaves. Plant Physiol. 2001;126:993-1000 pubmed..Irrespective of the mechanism, isoprene is one of the most effective antioxidants in plants. ..
- Affek H, Yakir D. Natural abundance carbon isotope composition of isoprene reflects incomplete coupling between isoprene synthesis and photosynthetic carbon flow. Plant Physiol. 2003;131:1727-36 pubmed
- Mayrhofer S, Teuber M, Zimmer I, Louis S, Fischbach R, Schnitzler J. Diurnal and seasonal variation of isoprene biosynthesis-related genes in grey poplar leaves. Plant Physiol. 2005;139:474-84 pubmed
- Loreto F, Velikova V. Isoprene produced by leaves protects the photosynthetic apparatus against ozone damage, quenches ozone products, and reduces lipid peroxidation of cellular membranes. Plant Physiol. 2001;127:1781-7 pubmed..Irrespective of the mechanism, our results suggest that endogenous isoprene has an important antioxidant role in plants. ..
- Schnitzler J, Graus M, Kreuzwieser J, Heizmann U, Rennenberg H, Wisthaler A, et al. Contribution of different carbon sources to isoprene biosynthesis in poplar leaves. Plant Physiol. 2004;135:152-60 pubmed
- Loreto F, Pinelli P, Brancaleoni E, Ciccioli P. 13C labeling reveals chloroplastic and extrachloroplastic pools of dimethylallyl pyrophosphate and their contribution to isoprene formation. Plant Physiol. 2004;135:1903-7 pubmed..Refixation of unlabeled respiratory CO(2) in the light may explain incomplete labeling of isoprene emission, as we found a good association between these two parameters. ..
- Rosenstiel T, Potosnak M, Griffin K, Fall R, Monson R. Increased CO2 uncouples growth from isoprene emission in an agriforest ecosystem. Nature. 2003;421:256-9 pubmed..Our results highlight the potential for uncoupling isoprene emission from biomass accumulation in an agriforest species, and show that negative air-quality effects of proliferating agriforests may be offset by increases in CO2. ..
- Karl T, Fall R, Rosenstiel T, Prazeller P, Larsen B, Seufert G, et al. On-line analysis of the (13)CO(2) labeling of leaf isoprene suggests multiple subcellular origins of isoprene precursors. Planta. 2002;215:894-905 pubmed..The data obtained shed light on the half-lives of photosynthetic metabolites, exchanges of carbon between cellular pools, and suggest multiple origins of isoprene precursors in leaves. ..
- Rohr A, Wilkins C, Clausen P, Hammer M, Nielsen G, Wolkoff P, et al. Upper airway and pulmonary effects of oxidation products of (+)-alpha-pinene, d-limonene, and isoprene in BALB/c mice. Inhal Toxicol. 2002;14:663-84 pubmed..This may be important in the context of the etiology or exacerbation of lower airway symptoms in office workers, or of occupational asthma in workers involved in industrial cleaning operations. ..
- Loreto F, Delfine S. Emission of isoprene from salt-stressed Eucalyptus globulus leaves. Plant Physiol. 2000;123:1605-10 pubmed..The temperature dependence indicates that this alternative synthesis is also under enzymatic control. If this alternative synthesis still occurs in the chloroplasts, it may involve a thylakoid-bound isoprene synthase. ..
- Logan B, Monson R, Potosnak M. Biochemistry and physiology of foliar isoprene production. Trends Plant Sci. 2000;5:477-81 pubmed
- Scholpp J, Schubert J, Miekisch W, Geiger K. Breath markers and soluble lipid peroxidation markers in critically ill patients. Clin Chem Lab Med. 2002;40:587-94 pubmed..More detailed insights into inflammatory processes can be obtained when the volatile markers and the serum markers are considered together. ..
- Schubert J, Spittler K, Braun G, Geiger K, Guttmann J. CO(2)-controlled sampling of alveolar gas in mechanically ventilated patients. J Appl Physiol (1985). 2001;90:486-92 pubmed..By using the new sampling technique, sensitivity of breath analysis was nearly doubled...