@article{AbegazPeter1995, author = {Abegaz, Berhanu M. and Peter, Martin G.}, title = {Emodine and emodinanthrone rhamnoside acetates from fruits of rhamnus prinoides}, issn = {0031-9422}, year = {1995}, language = {en} } @article{AlarconAldereteAguilaetal.2005, author = {Alarcon, Julio and Alderete, Joel B. and Aguila, Sergio and Peter, Martin G.}, title = {Regio and stereoselective hydroxylation of alpha-agarofuran by biotransformation of rhizopus nigricans}, year = {2005}, abstract = {A new synthesis of 9 alpha-hydroxy-alpha-agarofuran (6 alpha) is described, using a microbiological hydroxylation alpha-agarofuran (5) as the key reaction. The stereochemistry of the biohydroxylation was determined on the basis of a NOESY-experiment and GIAO calculations at the B3LYP/cc-pVDZ level. A strong gamma-effect was observed at C15 of the agarofuran ring which was correctly predicted by the GIAO-B3LYP calculations}, language = {en} } @article{AlarconAlderetePeteretal.1998, author = {Alarcon, Julio and Alderete, Joel B. and Peter, Martin G. and Becerra, Juan J. and Silva, M.}, title = {Study on synthesis of 3 alpha,4 alpha-dihydroxy-dihydro-beta-agarofuran}, year = {1998}, language = {en} } @article{AndayiYenesewDereseetal.2006, author = {Andayi, Andrew W. and Yenesew, Abiy and Derese, Solomon and Midiwo, Jacob O. and Gitu, Peter M. and Jondiko, Ogoche J. I. and Akala, Hoseah M. and Liyala, Pamela and Wangui, Julia and Waters, Norman C. and Heydenreich, Matthias and Peter, Martin G.}, title = {Antiplasmodial flavonoids from Erythrina sacleuxii}, issn = {0032-0943}, doi = {10.1055/s-2005-873200}, year = {2006}, abstract = {The acetone extracts of the root bark and stem bark of Erythrina sacleuxii showed antiplasmodial activities against the chloroquine-sensitive (D6) and chloroquine-resistant (W2) strains of Plasmodium falciparum. Chromatographic separation of the acetone extract of the root bark afforded a new isoflavone, 7-hydroxy-4 -methoxy-3'- prenylisoflavone (trivial name 5-deoxy-3' - prenylbiochanin A) along with known isoflavonoids as the antiplasmodial principles. Flavonoids and isoflavonoids isolated from the stem bark of E. sucleuxii were also tested and showed antiplasmodial activities. The structures were determined on the basis of spectroscopic evidence}, language = {en} } @article{AndersenPeterRoepstorff1996, author = {Andersen, S. O. and Peter, Martin G. and Roepstorff, Peter}, title = {Cuticular sclerotization in insects}, year = {1996}, language = {en} } @article{BahrkeEinarssonGislasonetal.2002, author = {Bahrke, Sven and Einarsson, Jon M. and Gislason, Johannes and Haebel, Sophie and Letzel, Matthias C. and Peter-Katalinic, Jasna and Peter, Martin G.}, title = {Sequence analysis of chitooligosaccharides by matrix-assisted laser desorption ionization postsource decay mass spectrometry}, year = {2002}, abstract = {Oligosaccharides composed of 2-acetamido-2-deoxy-D-glucopyranose (GlcNAc) and/or 2-amino-2-deoxy-D- glucopyranose (GlcN) were prepd. by chem. degrdn. of chitin or chitosan and sepd. by gel permeation chromatog. Oligosaccharides obtained after enzymic hydrolysis of chitosan [FA 0.19] with a fungal chitinase were derivatized by reductive amination with 2-aminoacridone and sequenced by matrix-assisted laser desorption ionization time-of-flight postsource decay (PSD) mass spectrometry (MS). The sequence of a trimer, D1A2, was established as D-A-A. The compn. of a hexamer D3A3 was .apprx.65\% D-A-D-D-A-A and 35\% D-D-A-D-A-A. The PSD MS of a nonamer D5A4-amac revealed four isobaric species D-X-Y-D-X-Y-D-A-A, where A is GlcNAc, D is GlcN, and X and Y (X ¹ Y) are mutually either D or A. This structure motif was also obsd. in a dodecamer D7A5 which was composed of eight isobaric sequences of the general formula (D-X-Y)3- D-A-A.}, language = {en} } @phdthesis{BahrkeEinarssonGislasonetal.2003, author = {Bahrke, Sven and Einarsson, Jon M. and Gislason, Johannes and Haebel, Sophie and Peter-Katalinic, Jasna and Peter, Martin G.}, title = {Characterization of chitooligosaccharides by mass spectrometry}, isbn = {82-47-15901-5}, year = {2003}, language = {en} } @article{BeckerPeterPoolZobel2000, author = {Becker, Thomas W. and Peter, Martin G. and Pool-Zobel, Beatrice L.}, title = {Cellular effects of lignans : modulation of growth, oxidative DNA damage and cell metabolism in human colon cancer cells}, year = {2000}, language = {en} } @article{BerthDautzenbergPeter1998, author = {Berth, Gisela and Dautzenberg, Herbert and Peter, Martin G.}, title = {Physica-chemical characterization of chitosans in dilute solution}, isbn = {2-907922-57-2}, year = {1998}, language = {en} } @article{BerthDautzenbergPeter1998, author = {Berth, Gisela and Dautzenberg, Herbert and Peter, Martin G.}, title = {Physico-chemical characterization of chitosans varying in degree of acetylation}, issn = {0144-8617}, year = {1998}, language = {en} } @article{BringmannMutanyattaComarMaksimenkaetal.2008, author = {Bringmann, Gerhard and Mutanyatta-Comar, Joan and Maksimenka, Katja and Wanjohi, John M. and Heydenreich, Matthias and Brun, Reto and M{\"u}ller, Werner E. G. and Peter, Martin G. and Midiwo, Jacob O. and Yenesew, Abiy}, title = {Joziknipholones A and B : the first dimeric phenylanthraquinones, from the roots of Bulbine frutescens}, issn = {0947-6539}, year = {2008}, abstract = {From the roots of the African plant Bulbine frutescens (Asphodelaceae), two unprecedented novel dimeric phenylanthraquinones, named joziknipholones A and B, possessing axial and centrochirality, were isolated, together with six known compounds. Structural elucidation of the new metabolites was achieved by spectroscopic and chiroptical methods, by reductive cleavage of the central bond between the monomeric phenylanthraquinone and -anthrone portions with sodium dithionite, and by quantum chemical CD calculations. Based on the recently revised absolute axial configuration of the parent phenylanthraquinones, knipholone and knipholone anthrone, the new dimers were attributed to possess the P- configuration (i.e., with the acetyl portions below the anthraquinone plane) at both axes in the case of joziknipholone A, whereas in joziknipholone B, the knipholone part was found to be M-configured. Joziknipholones A and B are active against the chloroquine resistant strain K1 of the malaria pathogen, Plasmodium falciparum, and show moderate activity against murine leukemic lymphoma L5178y cells.}, language = {en} } @article{BussVarumPeteretal.1996, author = {Buss, U. and Varum, K. M. and Peter, Martin G. and Spindler-Barth, Margarethe}, title = {ELISA for quantitation of chitin, chitosan and related compounds}, year = {1996}, language = {en} } @phdthesis{DereseYenesewMidiwoetal.2003, author = {Derese, Solomon and Yenesew, Abiy and Midiwo, Jacob O. and Heydenreich, Matthias and Peter, Martin G.}, title = {A new isoflavone from stem bark of Millettia dura}, issn = {1011-3924}, year = {2003}, language = {en} } @article{EijsinkSynstadGaseidnesetal.2003, author = {Eijsink, Vincent G. H. and Synstad, Bjoenar and Gaseidnes, Sigrid and Komander, David and Houston, Douglas R. and Peter, Martin G. and van Aalten, Daan M. F.}, title = {Structure and function of chitinolytic enzymes}, isbn = {82-471-5901-5}, year = {2003}, abstract = {The recent work on a variety of family 18 chitonolytic enzymes has yielded important data concerning the structure, substrate-binding, catalysis, inhibitor-binding and even dynamics. These data have been useful in helping to better understand the roles of various types of chitinases in chitin hydrolysis, to rationally engineer the properties of these enzymes, thus making them more suitable as biocatalysts, and to study and understand the effectiveness of natural and designed chitinase inhibitors, which may be of medical interest. On the other hand, the recent work on ChiB shows that catalysis in family 18 chitinases is a highly complicated process, involving larger parts of the enzyme and dynamics. Thus, despite recent discoveries, there is still a lot more to discover about how these enzyme work.}, language = {en} } @article{FasciottiSanvidoSantosetal.2012, author = {Fasciotti, Maira and Sanvido, Gustavo B. and Santos, Vanessa G. and Lalli, Priscila M. and McCullagh, Michael and de Sa, Gilberto F. and Daroda, Romeu J. and Peter, Martin G. and Eberlin, Marcos N.}, title = {Separation of isomeric disaccharides by traveling wave ion mobility mass spectrometry using CO2 as drift gas}, series = {Journal of mass spectrometr}, volume = {47}, journal = {Journal of mass spectrometr}, number = {12}, publisher = {Wiley-Blackwell}, address = {Hoboken}, issn = {1076-5174}, doi = {10.1002/jms.3089}, pages = {1643 -- 1647}, year = {2012}, abstract = {The use of CO2 as a massive and polarizable drift gas is shown to greatly improve peak-to-peak resolution (Rp-p), as compared with N2, for the separation of disaccharides in a Synapt G2 traveling wave ion mobility cell. Near or baseline Rp-p was achieved for three pairs of sodiated molecules of disaccharide isomers, that is, cellobiose and sucrose (Rp-p?=?0.76), maltose and sucrose (Rp-p?=?1.04), and maltose and lactose (Rp-p?=?0.74). Ion mobility mass spectrometry using CO2 as the drift gas offers therefore an attractive alternative for fast and efficient separation of isomeric disaccharides.}, language = {en} } @misc{FerenzPeter1987, author = {Ferenz, Hans-J{\"o}rg and Peter, Martin G.}, title = {The inhibitory effect of sinefungin on juvenile hormone biosynthesis and development in locusts}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-16811}, year = {1987}, abstract = {The antibiotic fungal metabolite sinefungin is a potent inhibitor of S-adenosylmethionine-acceptor methyltransferases. Its effect on insect metabolism and especially on corpora allata farnesoic acid methyltransferase, which catalyzes the penultimate step of juvenile hormone biosynthesis, was investigated in Locusta migratoria. Injection of sinefungin results in a delay of imaginal molt and in suppression of ovary development. Isolated corpora allata are unable to synthesize juvenile hormone III in the presence of more than 1.0 mM sinefungin. In a cell-free system containing the S-adenosylmethionine-dependent farnesoic acid methyltransferase from corpora allata sinefungin is a competitive inhibitor of the synthesis of methylfarnesoate with Ki of 1 μM.}, language = {en} } @misc{FerenzPeterBerg1983, author = {Ferenz, Hans-J{\"u}rgen and Peter, Martin G. and Berg, Dieter}, title = {Inhibition of farnesoic acid methyltransferase by sinefungin}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17016}, year = {1983}, abstract = {Sinefungin inhibited the S-adenosylmethionine-dependent farnesoic acid methyltransferase in a cell-free system containing a homogenate of corpora allata from female locusts, Locusta migratoria. The enzyme catalyzed the penultimate step of juvenile hormone biosynthesis in the insects. Culturing corpora allata in the presence of sinefungin greatly suppressed juvenile hormone production. The following in vivo effects were visible after injection of the inhibitor: increase in mortality and reduction of total haemolymph protein liter and ovary fresh weight, as well as length of terminal oocytes. Attempts to reverse these effects by topical application of the juvenile hormone analog ZR-515 (methoprene) were only partly successful. Therefore, the in vivo effects may be due to a general inhibition of methyltransferase enzymes in the insect. Sinefungin appeared to be of potential interest as the first representative of a new class of insect growth regulators.}, language = {en} } @article{FettkePeikowPeteretal.2009, author = {Fettke, Anja and Peikow, Dirk and Peter, Martin G. and Kleinpeter, Erich}, title = {Synthesis and conformational analysis of glycomimetic analogs of thiochitobiose}, issn = {0040-4020}, doi = {10.1016/j.tet.2009.03.067}, year = {2009}, abstract = {The synthesis of six analogs of N,N;-diacetylchitobiose is reported, including a novel transglycosylation reaction for the preparation of S-aryl thioglycosides. The conformations of the compounds were studied by a combination of NMR spectroscopy and molecular modeling, using force field calculations. In the case of the S-aryl thioglycosides with exclusively S-glycosidic linkages, dihedral angles of the disaccharidic S-glycosidic bonds, ;; and ;; and of the S-arylglycoside bonds, ; and ;, were found to be similar, whereas they were different in mixed glycosides and in a thiazoline derivative. An adequate correlation between the calculated H,H-distances of the local minima and the measured NOE contacts was achieved by applying population-weighted averages over participating conformers based on weighted relative energies.}, language = {en} } @article{FotieNkengfackPeteretal.2004, author = {Fotie, J. and Nkengfack, A. E. and Peter, Martin G. and Heydenreich, Matthias and Fomum, Z. T.}, title = {Chemical constituents of the ethyl acetate extracts of the stem bark and fruits of Dichrostachys cinerea and the roots of Parkia bicolor}, issn = {1011-3924}, year = {2004}, abstract = {The antibacterial activities of ethyl acetate, methanol and aqueous extracts of the stem bark of Dichrostachys cinerea and the roots of Parkia bicolor have been evaluated. Ethyl acetate extracts have been investigated, studies that led to a series of known compounds, amongst which many are reported here for the very first time from both the species}, language = {en} } @article{GermerKlodPeteretal.2002, author = {Germer, Antje and Klod, Sabrina and Peter, Martin G. and Kleinpeter, Erich}, title = {NMR spectroscopic and theoretical study of the complexation of the inhibitor allosamidin in the binding pocket of the plant chitinase hevamine}, year = {2002}, abstract = {Based on NMR spectroscopic information about the allosamidin-hevamine complex, ab initio MO calcns. of the ring current effect of the arom. moieties of Trp255, Tyr183 and Tyr6 of hevamine were carried out to investigate the role of these amino acid residues in binding interactions with allosamidin in soln. In addn., the intermol. steric compression effect on the 13C chem. shifts of the allosamizoline carbon atoms and the hydrogen bonding to Glu127 was identified. It can be inferred that the binding forces are strongest in the allosamizoline moiety of allosamidin.}, language = {en} }