@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} } @article{LetzelPeterKatalinicPeter2001, author = {Letzel, Matthias C. and Peter-Katalinic, Jasna and Peter, Martin G.}, title = {Mass spectrometry of chitin and chitosan oligosaccharides}, year = {2001}, language = {en} } @misc{PeterAndersenHartmannetal.1992, author = {Peter, Martin G. and Andersen, Svend Olav and Hartmann, Rudolf and Miessner, Merle and Roepstorff, Peter}, title = {Catecholamine-protein conjugates : isolation of 4-phenylphenoxazin-2-ones from oxidative coupling of N-acetyldopamine with alipathic amino acids}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17571}, year = {1992}, abstract = {4-Phenylphenoxazinones were isolated after biomimetic oxidation, using diphenoloxidases of insect cuticle, mushroom tyrosinase, or after autoxidation of N-acetyldopamine (Image ) in the presence of β-alanine, β-alanine methyl ester or N-acetyl-L-lysine. They are formed presumably by addition of 2-aminoalkyl-5-alkylphenols to the o-quinone of biphenyltetrol which, in turn, arises from oxidative coupling of. The structures of present the first examples for the assembly of reasonably stable intermediates in the rather complex process of chemical modifications of aliphatic amino acid residues by o-quinones.}, language = {en} } @misc{PeterStuppLentes1983, author = {Peter, Martin G. and Stupp, Hans-Peter and Lentes, Klaus-Ulrich}, title = {Umkehr der Enantioselektivit{\"a}t bei der enzymatischen Hydrolyse von Juvenilhormon als Ergebnis einer Proteinfraktionierung}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17001}, year = {1983}, abstract = {Aus dem Inhalt: Die Juvenilhormone 1a-c werden im Blut von Insekten enzymatisch zu den biologisch inaktiven Sluren hydrolysiert. Bei der Hydrolyse von racemischem 1c im Blut der Wanderheuschrecke Locusta migratoria wird ein Umsatz von 40-60\% erreicht. Das unumgesetzte Edukt enth{\"a}llt einen {\"U}berschuß an nat{\"u}rlich konfiguriertem (10R)-1c (e.e. 47.2\%). Wir konnten zeigen, daß das in der H{\"a}molymphe vorhandene Hormon-Bindungsprotein bevorzugt mit (10R)- 1c assoziiert.}, language = {de} } @article{JumaAkalaEyaseetal.2011, author = {Juma, Wanyama P. and Akala, Hoseah M. and Eyase, Fredrick L. and Muiva, Lois M. and Heydenreich, Matthias and Okalebo, Faith A. and Gitu, Peter M. and Peter, Martin G. and Walsh, Douglas S. and Imbuga, Mabel and Yenesew, Abiy}, title = {Terpurinflavone an antiplasmodial flavone from the stem of Tephrosia Purpurea}, series = {Phytochemistry letters}, volume = {4}, journal = {Phytochemistry letters}, number = {2}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1874-3900}, doi = {10.1016/j.phytol.2011.02.010}, pages = {176 -- 178}, year = {2011}, abstract = {The stem extract of Tephrosia purpurea showed antiplasmodial activity against the D6 (chloroquine-sensitive) and W2 (chloroquine-resistant) strains of Plasmodium falciparum with IC(50) values of 10.47 +/- 2.22 mu g/ml and 12.06 +/- 2.54 mu g/ml, respectively. A new prenylated flavone, named terpurinflavone, along with the known compounds lanceolatin A, (-)-semiglabrin and lanceolatin B have been isolated from this extract. The new compound, terpurinflavone, showed the highest antiplasmodial activity with IC(50) values of 3.12 +/- 0.28 mu M (D6) and 6.26 +/- 2.66 mu M (W2). The structures were determined on the basis of spectroscopic evidence.}, 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{SchulzeMakuchWagnerKounavesetal.2018, author = {Schulze-Makuch, Dirk and Wagner, Dirk and Kounaves, Samuel P. and Mangelsdorf, Kai and Devine, Kevin G. and de Vera, Jean-Pierre and Schmitt-Kopplin, Philippe and Grossart, Hans-Peter and Parro, Victor and Kaupenjohann, Martin and Galy, Albert and Schneider, Beate and Airo, Alessandro and Froesler, Jan and Davila, Alfonso F. and Arens, Felix L. and Caceres, Luis and Cornejo, Francisco Solis and Carrizo, Daniel and Dartnell, Lewis and DiRuggiero, Jocelyne and Flury, Markus and Ganzert, Lars and Gessner, Mark O. and Grathwohl, Peter and Guan, Lisa and Heinz, Jacob and Hess, Matthias and Keppler, Frank and Maus, Deborah and McKay, Christopher P. and Meckenstock, Rainer U. and Montgomery, Wren and Oberlin, Elizabeth A. and Probst, Alexander J. and Saenz, Johan S. and Sattler, Tobias and Schirmack, Janosch and Sephton, Mark A. and Schloter, Michael and Uhl, Jenny and Valenzuela, Bernardita and Vestergaard, Gisle and Woermer, Lars and Zamorano, Pedro}, title = {Transitory microbial habitat in the hyperarid Atacama Desert}, series = {Proceedings of the National Academy of Sciences of the United States of America}, volume = {115}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, number = {11}, publisher = {National Acad. of Sciences}, address = {Washington}, issn = {0027-8424}, doi = {10.1073/pnas.1714341115}, pages = {2670 -- 2675}, year = {2018}, 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{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{SchumacherWanderslebPetersenPeter1994, author = {Schumacher-Wandersleb, Michael H. M. G. and Petersen, Stefan and Peter, Martin G.}, title = {Preparation of the N-Acetylglucosaminidase inhibitor 1-Acetamido-1,2,5-tride oxy-2,5-imino-D-glucitol from methyl a-D-Mannopyranoside}, year = {1994}, language = {en} }