jump to searchjump to navigationjump to content

Publications - Cell and Metabolic Biology

Sort by: Year Type of publication

Displaying results 171 to 180 of 409.

Publications

Kopycki, J.G., Rauh, D., Chumanevich, A.A., Neumann, P., Vogt, T. & Stubbs, M.T. Biochemical and structural analysis of substrate promiscuity in plant Mg2+-dependent O-methyltransferases J. Mol. Biol 378, 154-164, (2008)

0
Publications

Schaarschmidt, S. & Hause, B. Apoplastic invertases: multi-faced players in the arbuscular mycorrhization Plant Signaling & Behavior 3, 317-319, (2008)

0
Publications

Sun, Z., Hans, J., Walter, M.H., Matusova, R., Beekwilder, J., Verstappen, F.W.A., Ming, Z., van Echtelt, E., Strack, D., Bisseling, T. & Bouwmeester, H.J. Cloning and characterisation of a maize carotenoid cleavage dioxygenase (ZmCCD1) and its involvement in the biosynthesis of apocarotenoids with various roles in mutualistic and parasitic interactions Planta 228, 789-801 , (2008)

0
Publications

Felker, P., Stinzing, F., Müssig, E., Leitenberger, M., Carle, R., Vogt, T. & Bunch, R. Color inheritance in cactus pear (Opuntia ficus-indica) fruits Ann. Appl. Biol 152, 307-318, (2008)

0
Publications

Engler, C., Kandzia, R. & Marillonnet, S. A one pot, one step, precision cloning method with high throughput capability PLOS One 3, e3647, (2008)

0
Publications

Geissler, R., Brandt, W. & Ziegler, J. Molecular modelling and site-directed mutagenesis re-veals the benzylisoquinoline binding site of the short-chain dehydrogenase/reductase salu-taridine reductase Plant Physiol 143, 1493-1503, (2007) DOI: ​10.​1104/​pp.​106.​095166

Recently, the NADPH-dependent short-chain dehydrogenase/reductase (SDR) salutaridine reductase (E.C. 1.1.1.248) implicated in morphine biosynthesis was cloned from Papaver somniferum. In this report, a homology model of the Papaver bracteatum homolog was created based on the x-ray structure of human carbonyl reductase 1. The model shows the typical α/β-folding pattern of SDRs, including the four additional helices αF′-1 to αF′-4 assumed to prevent the dimerization of the monomeric short-chain dehyrogenases/reductases. Site-directed mutagenesis of asparagine-152, serine-180, tyrosine-236, and lysine-240 resulted in enzyme variants with strongly reduced performance or inactive enzymes, showing the involvement of these residues in the proton transfer system for the reduction of salutaridine. The strong preference for NADPH over NADH could be abolished by replacement of arginine residues 44 and 48 by glutamic acid, confirming the interaction between the arginines and the 2′-phosphate group. Docking of salutaridine into the active site revealed nine amino acids presumably responsible for the high substrate specificity of salutaridine reductase. Some of these residues are arranged in the right position by an additional αE′ helix, which is not present in SDRs analyzed so far. Enzyme kinetic data from mutagenic replacement emphasize the critical role of these residues in salutaridine binding and provide the first data on the molecular interaction of benzylisoquinoline alkaloids with enzymes. 

Publications

Mittasch, J., Strack, D. & Milkowski, C. Secondary product glycosyltransferases in seeds of Brassica napus Planta 225, 515-522, (2007) DOI: 10.1007/s00425-006-0360-7

This study describes a systematic screen for secondary product UDP-glycosyltransferases (UGTs; EC 2.4.1) involved in seed development of oilseed rape (Brassica napus) and was aimed at identifying genes related to UGT84A9 encoding UDP-glucose:sinapate glucosyltransferase (EC 2.4.1.120), a proven target for molecular breeding approaches to reduce the content of anti-nutritive sinapate esters. By RT-PCR with primers recognizing the conserved signature motif of UGTs, 13 distinct ESTs could be generated from seed RNA. Sequence analysis allowed to assign the isolated ESTs to groups B, D, E, and L of the UGT family. In an alternative approach, two open reading frames related to UGT84A9 were cloned from the B. napus genome and designated as UGT84A10 and UGT84A11, respectively. Functional expression of UGT84A10 revealed that the encoded enzyme catalyzes the formation of 1-O-acylglucosides (β-acetal esters) with several hydroxycinnamates whereas, in our hands, the recombinant UGT84A11 did not display this enzymatic activity. Semi-quantitative RT-PCR confirmed that the majority of potential UGTs specified by the isolated ESTs is differentially expressed. A pronounced transcriptional up-regulation during seed development was evident for UGT84A9 and one EST (BnGT3) clustering in group E of UGTs. UGT84A10 was highly induced in flowers and expressed to a moderate level in late seed maturation indicating a possible involvement in seed-specific sinapate ester biosynthesis.

Publications

Stehle, F., Brand, W., Mikowski, C. & Strack, D. Corrigendum to “Structure determinants and substrate recognition of serine carboxypeptidase-like acyltransferases from plant secondary metabolism” [FEBS Lett. 580 (2006) 6366–6374] FEBS Letters 581, 164-165, (2007) DOI: 10.1016/j.febslet.2006.12.001

0
Publications

Fester, T., Lohse, S. & Halfmann, K. “Chromoplast” development in arbuscular mycorrhizal root. Phytochemistry 68, 92-100, (2007) DOI: 10.1016/j.phytochem.2006.09.034

The accumulation of apocarotenoids in arbuscular mycorrhizal (AM) roots suggests a dramatic reorganization of the plastids responsible for the biosynthesis of these compounds. This review describes the cytological and biochemical characterization of this phenomenon. The results presented suggest that plastids are key organelles for the establishment of the symbiotic interface of the AM symbiosis. In addition, a complex interplay of various plant cell components during the different functional phases of this interface is suggested. Arbuscule degradation appears to be of particular interest, as it correlates with the formation of the most extensive plastid structures and with apocarotenoid accumulation.

Books and chapters

Hinneburg, A., Porzel, A. & Wolfram, K. An evaluation of text retrieval methods for similarity search of multi-dimensional NMR-Spectra. In: Bioinformatics Research and Development.  Lecture Notes in Computer Science 4414, 424-438, (2007) ISBN: 978-3-540-71232-9 DOI: 10.1007/978-3-540-71233-6_33

Searching and mining nuclear magnetic resonance (NMR)-spectra of naturally occurring substances is an important task to investigate new potentially useful chemical compounds. Multi-dimensional NMR-spectra are relational objects like documents, but consists of continuous multi-dimensional points called peaks instead of words. We develop several mappings from continuous NMR-spectra to discrete text-like data. With the help of those mappings any text retrieval method can be applied. We evaluate the performance of two retrieval methods, namely the standard vector space model and probabilistic latent semantic indexing (PLSI). PLSI learns hidden topics in the data, which is in case of 2D-NMR data interesting in its owns rights. Additionally, we develop and evaluate a simple direct similarity function, which can detect duplicates of NMR-spectra. Our experiments show that the vector space model as well as PLSI, which are both designed for text data created by humans, can effectively handle the mapped NMR-data originating from natural products. Additionally, PLSI is able to find meaningful ”topics” in the NMR-data.

IPB Mainnav Search