TY  - JOUR
A1  - Letzel, Matthias C.
A1  - Synstad, Bjoenar
A1  - Eijsink, Vincent G. H.
A1  - Peter-Katalinic, Jasna
A1  - Peter, Martin G.
T1  - Libraries of chito-oligosaccharides of mixed acetylation patterns and their interactions with chitinases
Y1  - 1999
SN  - 3-9806494-5-8
ER  - 
TY  - JOUR
A1  - Yenesew, Abiy
A1  - Twinomuhwezi, Hannington
A1  - Kiremire, Bernard T.
A1  - Mbugua, Martin N.
A1  - Gitu, Peter M.
A1  - Heydenreich, Matthias
A1  - Peter, Martin G.
T1  - 8-Methoxyneorautenol and radical scavenging flavonoids from Erythrina abyssinica
N2  - A new pterocarpan (named 8-methoxyneorautenol) was isolated from the acetone ext. of the root bark of Erythrina abyssinica. In addn., the known isoflavonoid derivs. eryvarin L, erycristagallin and shinpterocarpin were identified for the first time from the roots of this plant. The structures were detd. on the basis of spectroscopic evidence. The new compd. showed selective antimicrobial activity against Trichophyton mentagrophytes. The acetone ext. of the root bark of E. abyssinica showed radical scavenging activity towards 2,2-diphenyl-1-picrylhydrazyl radical (DPPH). The pterocarpenes, 3-hydroxy-9-methoxy-10-(3,3-dimethylallyl)pterocarpene and erycristagallin, were the most active constituents of the roots of this plant and showing dose-dependent activities similar to that of the std. quercetin. [on SciFinder (R)]
Y1  - 2009
UR  - http://www.ajol.info/journal_index.php?jid=120&ab=bcse
SN  - 1011-3924
ER  - 
TY  - GEN
A1  - Peter, Martin G.
A1  - Boldt, Peter C.
A1  - Niederstein, Yvonne
A1  - Peter-Katalinić, Jasna
T1  - Synthesen von Galactose-Cluster-haltigen Steroid-Derivaten
N2  - The synthesis of galactose clusters that are linked to a steroid moiety by a peptide-like spacer unit is described. The galactose cluster is obtained by Koenigs-Knorr glycosylation of TRIS-Gly-Fmoc (2b) under Helferich conditions. Peptide and ester bonds are formed after activation of carboxylic acids as diphenylthiophene dioxide (TDO) esters. 6a is synthesized in a convergent way by coupling of (Ac4Gal)3-TRIS-Gly (3e) with cholesteryl TDO succinate (5b). Coupling of (Ac4Gal)3-TRIS-Gly hydrogen succinate (3f) with Gly-O-Chol (5d) by means of EEDQ yields 6d. Reaction of (Ac4Gal)3-TRIS-Gly-SUCC-O-TDO (3g) with 25-hydroxycholesterol leads in a linear sequence to the oxysterol derivative 6f. Selective cleavage of the acetyl groups from galactose units yields the known compound 6b and the new derivatives 6e and 6g.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - paper 042 
KW  - Glycoconjugates
KW  - Galactosides
KW  - Steroid esters
KW  - Amphiphiles
KW  - Glycopeptides
Y1  - 1990
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-16783
ER  - 
TY  - JOUR
A1  - Vaaje-Kolstad, G.
A1  - Vasella, A.
A1  - Peter, Martin G.
A1  - Netter, C.
A1  - Houston, Douglas R.
A1  - Westereng, B.
A1  - Synstad, Bjoenar
A1  - Eijsink, Vincent G. H.
A1  - van Aalten, Daan M. F.
T1  - Interactions of a family 18 chitinase with the designed inhibitor HM508 and its degradation product, chitobiono- delta-lactone
N2  - We describe enzymological and structural analyses of the interaction between the family 18 chitinase ChiB from Serratia marcescens and the designed inhibitor N,N'-diacetylchitobionoxime-N-phenylcarbamate (HM508). HM508 acts as a competitive inhibitor of this enzyme with a K-i in the 50 muM range. Active site mutants of ChiB show K-i values ranging from 1 to 200 muM, providing insight into some of the interactions that determine inhibitor affinity. Interestingly, the wild type enzyme slowly degrades HM508, but the inhibitor is essentially stable in the presence of the moderately active D142N mutant of ChiB. The crystal structure of the D142N-HM508 complex revealed that the two sugar moieties bind to the -2 and -1 subsites, whereas the phenyl group interacts with aromatic side chains that line the +1 and +2 subsites. Enzymatic degradation of HM508, as well as a Trp-->Ala mutation in the +2 subsite of ChiB, led to reduced affinity for the inhibitor, showing that interactions between the phenyl group and the enzyme contribute to binding. Interestingly, a complex of enzymatically degraded HM508 with the wild type enzyme showed a chitobiono-delta- lactone bound in the -2 and -1 subsites, despite the fact that the equilibrium between the lactone and the hydroxy acid forms in solution lies far toward the latter. This shows that the active site preferentially binds the E-4 conformation of the -1 sugar, which resembles the proposed transition state of the reaction
Y1  - 2004
SN  - 0021-9258
ER  - 
TY  - JOUR
A1  - Rottmann, Antje
A1  - Synstad, Bjoenar
A1  - Thiele, G.
A1  - Schanzenbach, Dirk
A1  - Eijsink, Vincent G. H.
A1  - Peter, Martin G.
T1  - Approaches towards the design of new chitinase inhibitors
Y1  - 1999
SN  - 3-9806494-5-8
ER  - 
TY  - THES
A1  - Bahrke, Sven
A1  - Einarsson, Jon M.
A1  - Gislason, Johannes
A1  - Haebel, Sophie
A1  - Peter-Katalinic, Jasna
A1  - Peter, Martin G.
T1  - Characterization of chitooligosaccharides by mass spectrometry
Y1  - 2003
SN  - 82-47-15901-5
ER  - 
TY  - JOUR
A1  - Rusu, Viorel Marin
A1  - Ng, C. H.
A1  - Wilke, Max
A1  - Tiersch, Brigitte
A1  - Fratzl, Peter
A1  - Peter, Martin G.
T1  - Size-controlled hydroxyapatite nanoparticles as self-organized organic-in organic composite materials
N2  - This paper presents some results concerning the size-controlled hydroxyapatite nanoparticles obtained in aqueous media in a biopolymer matrix from soluble precursors salts. Taking the inspiration from nature, where composite materials made of a polymer matrix and inorganic fillers are often found, e.g. bone, shell of crustaceans, shell of eggs, etc., the feasibility on making composite materials containing chitosan and nanosized hydroxyapatite was investigated. A stepwise co-precipitation approach was used to obtain different types of composites by means of different ratio between components. The synthesis of hydroxyapatite was carried out in the chitosan matrix from calcium chloride and sodium dihydrogenphosphate in alkaline solutions at moderate pH of 10-11 for 24 h. Our research is focused on studying and understanding the structure of this class of composites, aiming at the development of novel materials, controlled at the nanolevel scale. The X-ray diffraction technique was employed in order to study the kinetic of hydroxyapatite formation in the chitosan matrix as well as to determine the HAp crystallite sizes in the composite samples. The hydroxyapatite synthesized using this route was found to be nano-sized (15-50nm). Moreover, applying an original approach to analyze the (002) XRD diffraction peak profile of hydroxyapatite by using a sum of two Gauss functions, the bimodal distribution of nanosized hydroxyapatite within the chitosan matrix was revealed. Two types of size distribution domains such as cluster-like (between 200 and 400 nm), which are the habitat of "small" hydroxyapatite nanocrystallites and scattered-like, which are the habitat of "large" hydroxyapatite nanocrystallites was probed by TEM and CSLM. The structural features of composites suggest that self-assembly processes might be involved. The composites contain nanosized hydroxyapatite with structural features close to those of biological apatites that make them attractive for bone tissue engineering applications. (c) 2005 Elsevier Ltd. All rights reserved
Y1  - 2005
SN  - 0142-9612
ER  - 
TY  - GEN
A1  - Peter, Martin G.
A1  - Andersen, Svend Olav
A1  - Hartmann, Rudolf
A1  - Miessner, Merle
A1  - Roepstorff, Peter
T1  - Catecholamine-protein conjugates : isolation of 4-phenylphenoxazin-2-ones from oxidative coupling of N-acetyldopamine with alipathic amino acids
N2  - 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.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - paper 062 
Y1  - 1992
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-17571
ER  - 
TY  - GEN
A1  - Peter, Martin G.
A1  - Stupp, Hans-Peter
A1  - Lentes, Klaus-Ulrich
T1  - Umkehr der Enantioselektivität bei der enzymatischen Hydrolyse von Juvenilhormon als Ergebnis einer Proteinfraktionierung
N2  - 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 enthällt einen Überschuß an natürlich konfiguriertem (10R)-1c (e.e. 47.2%). Wir konnten zeigen, daß das in der Hämolymphe vorhandene Hormon-Bindungsprotein bevorzugt mit (10R)- 1c assoziiert.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - paper 052 
Y1  - 1983
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-17001
ER  - 
TY  - JOUR
A1  - Andersen, S. O.
A1  - Peter, Martin G.
A1  - Roepstorff, Peter
T1  - Cuticular sclerotization in insects
Y1  - 1996
ER  - 
TY  - JOUR
A1  - Haebel, Sophie
A1  - Peter-Katalinic, Jasna
A1  - Peter, Martin G.
T1  - Mass spectrometry of chitooligosaccharides
Y1  - 1997
SN  - 88-86889- 01-1
ER  - 
TY  - JOUR
A1  - Bahrke, Sven
A1  - Einarsson, Jon M.
A1  - Gislason, Johannes
A1  - Haebel, Sophie
A1  - Letzel, Matthias C.
A1  - Peter-Katalinic, Jasna
A1  - Peter, Martin G.
T1  - Sequence analysis of chitooligosaccharides by matrix-assisted laser desorption ionization postsource decay mass spectrometry
N2  - 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.
Y1  - 2002
ER  - 
TY  - JOUR
A1  - Letzel, Matthias C.
A1  - Peter-Katalinic, Jasna
A1  - Peter, Martin G.
T1  - Mass spectrometry of chitin and chitosan oligosaccharides
Y1  - 2001
ER  - 
TY  - JOUR
A1  - Juma, Wanyama P.
A1  - Akala, Hoseah M.
A1  - Eyase, Fredrick L.
A1  - Muiva, Lois M.
A1  - Heydenreich, Matthias
A1  - Okalebo, Faith A.
A1  - Gitu, Peter M.
A1  - Peter, Martin G.
A1  - Walsh, Douglas S.
A1  - Imbuga, Mabel
A1  - Yenesew, Abiy
T1  - Terpurinflavone an antiplasmodial flavone from the stem of Tephrosia Purpurea
JF  - Phytochemistry letters
N2  - 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.
KW  - Tephrosia purpurea
KW  - Leguminosae
KW  - Stem
KW  - Flavone
KW  - Terpurinflavone
KW  - Antiplasmodial
Y1  - 2011
U6  - https://doi.org/10.1016/j.phytol.2011.02.010
SN  - 1874-3900
VL  - 4
IS  - 2
SP  - 176
EP  - 178
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Andayi, Andrew W.
A1  - Yenesew, Abiy
A1  - Derese, Solomon
A1  - Midiwo, Jacob O.
A1  - Gitu, Peter M.
A1  - Jondiko, Ogoche J. I.
A1  - Akala, Hoseah M.
A1  - Liyala, Pamela
A1  - Wangui, Julia
A1  - Waters, Norman C.
A1  - Heydenreich, Matthias
A1  - Peter, Martin G.
T1  - Antiplasmodial flavonoids from Erythrina sacleuxii
N2  - 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
Y1  - 2006
UR  - http://www.thieme-connect.com/ejournals/toc/plantamedica
U6  - https://doi.org/10.1055/s-2005-873200
SN  - 0032-0943
ER  - 
TY  - JOUR
A1  - Schulze-Makuch, Dirk
A1  - Wagner, Dirk
A1  - Kounaves, Samuel P.
A1  - Mangelsdorf, Kai
A1  - Devine, Kevin G.
A1  - de Vera, Jean-Pierre
A1  - Schmitt-Kopplin, Philippe
A1  - Grossart, Hans-Peter
A1  - Parro, Victor
A1  - Kaupenjohann, Martin
A1  - Galy, Albert
A1  - Schneider, Beate
A1  - Airo, Alessandro
A1  - Froesler, Jan
A1  - Davila, Alfonso F.
A1  - Arens, Felix L.
A1  - Caceres, Luis
A1  - Cornejo, Francisco Solis
A1  - Carrizo, Daniel
A1  - Dartnell, Lewis
A1  - DiRuggiero, Jocelyne
A1  - Flury, Markus
A1  - Ganzert, Lars
A1  - Gessner, Mark O.
A1  - Grathwohl, Peter
A1  - Guan, Lisa
A1  - Heinz, Jacob
A1  - Hess, Matthias
A1  - Keppler, Frank
A1  - Maus, Deborah
A1  - McKay, Christopher P.
A1  - Meckenstock, Rainer U.
A1  - Montgomery, Wren
A1  - Oberlin, Elizabeth A.
A1  - Probst, Alexander J.
A1  - Saenz, Johan S.
A1  - Sattler, Tobias
A1  - Schirmack, Janosch
A1  - Sephton, Mark A.
A1  - Schloter, Michael
A1  - Uhl, Jenny
A1  - Valenzuela, Bernardita
A1  - Vestergaard, Gisle
A1  - Woermer, Lars
A1  - Zamorano, Pedro
T1  - Transitory microbial habitat in the hyperarid Atacama Desert
JF  - Proceedings of the National Academy of Sciences of the United States of America
KW  - habitat
KW  - aridity
KW  - microbial activity
KW  - biomarker
KW  - Mars
Y1  - 2018
U6  - https://doi.org/10.1073/pnas.1714341115
SN  - 0027-8424
VL  - 115
IS  - 11
SP  - 2670
EP  - 2675
PB  - National Acad. of Sciences
CY  - Washington
ER  - 
TY  - JOUR
A1  - Eijsink, Vincent G. H.
A1  - Synstad, Bjoenar
A1  - Gaseidnes, Sigrid
A1  - Komander, David
A1  - Houston, Douglas R.
A1  - Peter, Martin G.
A1  - van Aalten, Daan M. F.
T1  - Structure and function of chitinolytic enzymes
N2  - 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.
Y1  - 2003
SN  - 82-471-5901-5
ER  - 
TY  - JOUR
A1  - Bringmann, Gerhard
A1  - Mutanyatta-Comar, Joan
A1  - Maksimenka, Katja
A1  - Wanjohi, John M.
A1  - Heydenreich, Matthias
A1  - Brun, Reto
A1  - Müller, Werner E. G.
A1  - Peter, Martin G.
A1  - Midiwo, Jacob O.
A1  - Yenesew, Abiy
T1  - Joziknipholones A and B : the first dimeric phenylanthraquinones, from the roots of Bulbine frutescens
N2  - 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.
Y1  - 2008
UR  - http://www3.interscience.wiley.com/journal/26293/home?CRETRY=1&SRETRY=0
SN  - 0947-6539
ER  - 
TY  - JOUR
A1  - Schumacher-Wandersleb, Michael H. M. G.
A1  - Petersen, Stefan
A1  - Peter, Martin G.
T1  - Preparation of the N-Acetylglucosaminidase inhibitor 1-Acetamido-1,2,5-tride oxy-2,5-imino-D-glucitol from methyl a-D-Mannopyranoside
Y1  - 1994
ER  - 
TY  - JOUR
A1  - Peter, Martin G.
A1  - Ley, J. P.
A1  - Petersen, Stefan
A1  - Londershausen, M.
A1  - Schumacher-Wandersleb, Michael H. M. G.
A1  - Spindler, Klaus-Dieter
A1  - Spindler-Barth, Margarethe
A1  - Turberg, Andreas
T1  - Synthesis of chitinase inhibitors
Y1  - 1994
ER  - 
TY  - JOUR
A1  - Rukunga, G. M.
A1  - Muregi, F. W.
A1  - Omar, S. A.
A1  - Gathirwa, J. W.
A1  - Muthaura, C. N.
A1  - Peter, Martin G.
T1  - Anti-plasmodial activity of the extracts and two sesquiterpenes from Cyperus articulatus
N2  - Two sesquiterpenes, corymbolone and mustakone, isolated from the chloroform extract of the rhizomes of Cyperus articulatus, exhibited significant anti-plasmodial properties. Mustakone was approximately ten times more active than corymbolone against the sensitive strains of the Plasmodium falciparum.
Y1  - 2008
SN  - 0367-326X
ER  - 
TY  - JOUR
A1  - Streffer, Katrin
A1  - Kaatz, Helvi
A1  - Bauer, Christian G.
A1  - Makower, Alexander
A1  - Schulmeister, Thomas
A1  - Scheller, Frieder W.
A1  - Peter, Martin G.
A1  - Wollenberger, Ursula
T1  - Application of a sensitive catechol detector for determination of tyrosinase inhibitors
Y1  - 1998
ER  - 
TY  - JOUR
A1  - Schumacher-Wandersleb, Michael H. M. G.
A1  - Peter, Martin G.
T1  - Synthesis of chitobiosyl pyrrolidines
Y1  - 1995
ER  - 
TY  - JOUR
A1  - Fasciotti, Maira
A1  - Sanvido, Gustavo B.
A1  - Santos, Vanessa G.
A1  - Lalli, Priscila M.
A1  - McCullagh, Michael
A1  - de Sa, Gilberto F.
A1  - Daroda, Romeu J.
A1  - Peter, Martin G.
A1  - Eberlin, Marcos N.
T1  - Separation of isomeric disaccharides by traveling wave ion mobility mass spectrometry using CO2 as drift gas
JF  - Journal of mass spectrometr
N2  - 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.
KW  - isomer resolution
KW  - oligosaccharides
KW  - traveling wave ion mobility mass spectrometry
KW  - polarizable drift gases
Y1  - 2012
U6  - https://doi.org/10.1002/jms.3089
SN  - 1076-5174
VL  - 47
IS  - 12
SP  - 1643
EP  - 1647
PB  - Wiley-Blackwell
CY  - Hoboken
ER  - 
TY  - JOUR
A1  - Houston, Douglas R.
A1  - Shiomi, Kazuro
A1  - Arai, Noriko
A1  - Omura, Satoshi
A1  - Peter, Martin G.
A1  - Turberg, Andreas
A1  - Synstad, Bjoenar
A1  - Eijsink, Vincent G. H.
A1  - Van Aalten, Daan M. F.
T1  - High-resolution structures of a chitinase complexed with natural product cyclopentapeptide inhibitors : mimicry of carbohydrate substrate
N2  - Over the past years, family 18 chitinases have been validated as potential targets for the design of drugs against human pathogens that contain or interact with chitin during their normal life cycles. Thus far, only one potent chitinase inhibitor has been described in detail, the pseudotrisaccharide allosamidin. Recently, however, two potent natural-product cyclopentapeptide chitinase inhibitors, argifin and argadin, were reported. Here, we describe high- resoln. crystal structures that reveal the details of the interactions of these cyclopeptides with a family 18 chitinase. The structures are examples of complexes of a carbohydrate-processing enzyme with high-affinity peptide-based inhibitors and show in detail how the peptide backbone and side chains mimic the interactions of the enzyme with chitooligosaccharides. Together with enzymol. characterization, the structures explain why argadin shows an order of magnitude stronger inhibition than allosamidin, whereas argifin shows weaker inhibition. The peptides bind to the chitinase in remarkably different ways, which may explain the differences in inhibition consts. The two complexes provide a basis for structure-based design of potent chitinase inhibitors, accessible by std. peptide chem.
Y1  - 2002
ER  - 
TY  - JOUR
A1  - van Aalten, Daan M. F.
A1  - Komander, David
A1  - Synstad, Bjoenar
A1  - Gaseidnes, Sigrid
A1  - Peter, Martin G.
A1  - Eijsink, Vincent G. H.
T1  - Structural Insights into the catalytic mechanism of a family 18 exochitinase
N2  - Chitinase B (ChiB) from Serratia marcescens is a family 18 exochitinase whose catalytic domain has a TIM-barrel fold with a tunnel-shaped active site. We have solved structures of three ChiB complexes that reveal details of substrate binding, substrateassisted catalysis, and product displacement. The structure of an inactive ChiB mutant (E144Q) complexed with a pentameric substrate (binding in subsites 22 to 13) shows closure of the ''roof'' of the active site tunnel. It also shows that the sugar in the 21 position is distorted to a boat conformation, thus providing structural evidence in support of a previously proposed catalytic mechanism. The structures of the active enzyme complexed to Allosamidin (an analogue of a proposed reaction intermediate) and of the active enzyme soaked with pentameric substrate show events after cleavage of the glycosidic bond. The latter structure shows reopening of the roof of the active site tunnel and enzyme-assisted product displacement in the 11 and 12 sites, allowing a water molecule to approach the reaction center. Catalysis is accompanied by correlated structural changes in the core of the TIM barrel that involve conserved polar residues whose functions were hitherto unknown. These changes simultaneously contribute to stabilization of the reaction intermediate and alternation of the pKa of the catalytic acid during the catalytic cycle.
Y1  - 2002
ER  - 
TY  - JOUR
A1  - Rottmann, Antje
A1  - Synstad, Bjoenar
A1  - Eijsink, Vincent G. H.
A1  - Peter, Martin G.
T1  - Synthesis of N-acetylglucosaminyl and diacetylchitobiosyl amides of heterocyclic carboxylic acids as potential chitinase inhibitors
Y1  - 1999
ER  - 
TY  - JOUR
A1  - Thiele, Gabriela
A1  - Rottmann, Antje
A1  - Germer, Antje
A1  - Kleinpeter, Erich
A1  - Spindler, Klaus-Dieter
A1  - Synstad, Bjoenar
A1  - Eijsink, Vincent G. H.
A1  - Peter, Martin G.
T1  - Synthesis and conformational analysis of pseudosugar analogues of chitotriose
N2  - In this article, the synthesis of analogs of N,N',N''-triacetylchitotriose in which the central sugar residue was replaced by a succinic acid is presented. Mol. modeling calcns. revealed that the pseudotrisaccharides exist in low energy extended conformations which show similar space filling as N,N',N''-triacetylchitotriose. Of the N,N',N''-triacetylchitotriose pseudosugar analogs tested as chitinase inhibitors, none showed any appreciable competition (numerical data not presented). The conformational anal. along with further synthetic efforts will hopefully lead to more efficient pseudosaccharides as chitinase inhibitors.
Y1  - 2002
ER  - 
TY  - JOUR
A1  - Krösche, Christian
A1  - Crescenzi, Orlando
A1  - Hoffbauer, Wilfried
A1  - Jansen, Martin
A1  - Napolitano, Alessandra
A1  - Prota, Guiseppe
A1  - Peter, Martin G.
T1  - Synthesis of dopamines labelled with 13C in the alpha- or beta-side chain positions, and their application for structure studies on melanins by solid state NMR spectroscopy
Y1  - 1994
ER  - 
TY  - JOUR
A1  - Peikow, Dirk
A1  - Matern, Christa-Maria
A1  - Peter, Martin G.
A1  - Schilde, Uwe
T1  - Crystal structure of (1,4,7,10,13-pentaoxacyclopentadecane-O,O ',O '',O ''')(trifluoromethanesulfonato-O,O ')sodium, Na(C10H20O5)(CF3SO3)
N2  - C11H20F3NaO8S, monoclinic, P121/nil (no. 11), a = 7.947(1) angstrom, b = 12.056(1) angstrom, c = 9.083(1) angstrom, P = 106.01 (1)degrees, V = 836.4 angstrom(3), Z = 2, R-gt(F) = 0.043, wR(ref)(F-2) = 0.120, T = 210 K.
Y1  - 2005
ER  - 
TY  - JOUR
A1  - Alarcon, Julio
A1  - Alderete, Joel B.
A1  - Aguila, Sergio
A1  - Peter, Martin G.
T1  - Regio and stereoselective hydroxylation of alpha-agarofuran by biotransformation of rhizopus nigricans
N2  - 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
Y1  - 2005
ER  - 
TY  - JOUR
A1  - Fotie, J.
A1  - Nkengfack, A. E.
A1  - Peter, Martin G.
A1  - Heydenreich, Matthias
A1  - Fomum, Z. T.
T1  - Chemical constituents of the ethyl acetate extracts of the stem bark and fruits of Dichrostachys cinerea and the roots of Parkia bicolor
N2  - 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
Y1  - 2004
SN  - 1011-3924
ER  - 
TY  - JOUR
A1  - Berth, Gisela
A1  - Dautzenberg, Herbert
A1  - Peter, Martin G.
T1  - Physica-chemical characterization of chitosans in dilute solution
Y1  - 1998
SN  - 2-907922-57-2
ER  - 
TY  - JOUR
A1  - Kamlage, Stefan
A1  - Sefkow, Michael
A1  - Zimmermann, Nicole
A1  - Peter, Martin G.
T1  - Concise synthesis of (+)-beta-benzyl gamma-butyrolactones from butynediol
Y1  - 2002
ER  - 
TY  - JOUR
A1  - Peter, Martin G.
T1  - Chitin and Chitosan from Animal Sources
N2  - A review on the chem. and biochem. of chitin and the chem. and application of chitosan. The following topics were discussed: structure of chitin and chitosan; occurrence and physiol. functions of chitin; detection of chitin in animals and anal. of chitin and chitosan; biosynthesis and biodegrdn. of chitin in animals; prodn. of chitin and chitosan; properties of chitin and chitosan; and applications of chitin and chitosan.
Y1  - 2002
SN  - 3-527-30227-1
ER  - 
TY  - JOUR
A1  - Peter, Martin G.
T1  - Chitin and Chitosan from Fungi
Y1  - 2002
SN  - 3-527-30227-1
ER  - 
TY  - GEN
A1  - Ferenz, Hans-Jürgen
A1  - Peter, Martin G.
A1  - Berg, Dieter
T1  - Inhibition of farnesoic acid methyltransferase by sinefungin
N2  - 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.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - paper 077 
KW  - Juvenile hormone analogue
KW  - Orthoptera
KW  - Juvenile hormone
KW  - Biosynthesis
KW  - Enzyme
KW  - Corpora allata
KW  - In vitro
KW  - Biological activity
KW  - Enzyme inhibitor
Y1  - 1983
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-17016
ER  - 
TY  - GEN
A1  - Kort, C. A. D. de
A1  - Peter, Martin G.
A1  - Koopmanschap, A. B.
T1  - Binding and degradation of juvenile hormone III by haemolymph proteins of the Colorado potato beetle: a re-examination
N2  - The haemolymph of the adult Colorado potato beetle, Lepinotarsa decemlineata Say, contains a high molecular weight (MW > 200,000) JH-III specific binding protein. The Kd value of the protein for racemic JH-III is 1.3 ± 0.2 × 10−7 M. It has a lower affinity for racemic JH-I and it does not bind JH-III-diol or JH-III-acid. The binding protein does discriminate between the enantiomers of synthetic, racemic JH-III as was determined by stereochemical anaysis of the bound and the free JH-III. Incubation of racemic JH-III with crude haemolymph results in preferential formation of (10S)-JH-III-acid, the unnatural configuration. The JH-esterase present in L. decemlineata haemolymph is not enantioselective. It is concluded that the most important function of the binding protein is that of a specific carrier, protecting the natural hormone against degradation by esterases. The carrier does not protect JH-I as efficiently as the lower homologue.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - paper 068 
KW  - Juvenile hormone
KW  - Leptinotarsa decemlineata
KW  - JH-III-specific carrier protein
KW  - enantioselectivity
Y1  - 1983
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-16777
ER  - 
TY  - GEN
A1  - Peter, Martin G.
A1  - Förster, Hans
T1  - On the structure of Eumelanins : identification of constitutional patterns by solid-state NMR spectroscopy
N2  - Aus dem Inhalt: Melanins are complex polyphenolic polymers. They are usually formed in nature by enzyme-catalyzed oxidative polymerization of o-diphenols. The deep black eumelanins, derived from Dopa 1 or dopamine 3, are distinguished from the yellow to brown phaeomelanins obtained from Dopa in the presence of cysteine. Characteristic of eumelanins are the indole units, which are formed from catecholamines by intramolecular addition of the amino groups to the oxidatively generated o-quinones. [...]
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - paper 053 
Y1  - 1989
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-17027
ER  - 
TY  - JOUR
A1  - Wanjohi, John M.
A1  - Yenesew, Abiy
A1  - Midiwo, Jacob O.
A1  - Heydenreich, Matthias
A1  - Peter, Martin G.
A1  - Dreyer, M.
A1  - Reichert, M.
A1  - Bringmann, Gerhard
T1  - Three dimeric anthracene derivatives from the fruits of Bulbine abyssinica
N2  - From the fruits of Bulbine abyssinica three new dimeric anthracene derivatives, (P)-8,9,1',8'- tetrahydroxy-3,3'-dimethyl[10,7'-bianthracene]-1,4,9',10'- tetraone (trivial name abyquinone A), (10R)-1,4,8,1',8-pentahydroxy-3,3'-dimethyl-[10,7'-bianthracene]9,9',10' (10H)-trione (trivial name abyquinone B), and (10R)-3,4'-dihydro-1,4,8,3',8',9'-hexahydroxy-3,3'- dimethyl-[10,7'-biant hracene]9,1'(10H,2'H)-dione (trivial name abyquinone Q were isolated. Despite their structural differences, these three compounds are connected to each other by the apparently biomimetic conversion of abyquinone C (a preanthraquinonylanthrone with two stereogenic centers) into B (an anthraquinonylanthrone with one stereogenic center) and finally into A (an axially chiral bianthraquinone) under mild conditions, involving a highly efficient center-to-axis chirality transfer. In addition, the known anthraquinones islandicin and chrysophanol were identified. The structures were determined on the basis of spectroscopical evidences, chemical transformations, and quantum chemical CD calculations. (C) 2005 Elsevier Ltd. All rights reserved
Y1  - 2005
SN  - 0040-4020
ER  - 
TY  - JOUR
A1  - Yenesew, Abiy
A1  - Kiplagat, John T.
A1  - Derese, Solomon
A1  - Midiwo, Jacob O.
A1  - Kabaru, Jacques M.
A1  - Heydenreich, Matthias
A1  - Peter, Martin G.
T1  - Two unusual rotenoid derivatives, 7a-O-methyl-12a-hydroxydeguelol and spiro-13-homo-13-oxaelliptone, from the seeds of Derris trifoliata
N2  - The crude methanol extract of the seeds of Derris trifoliata showed potent and dose dependent larvicidal activity against the 2nd instar larvae of Aedes aegypti. From this extract two unusual rotenoid derivatives, a rotenoloid (named 7a-O-methyl-12a-hydroxydeguelol) and a spirohomooxarotenoid (named spiro-13-homo-13-oxaelliptone), were isolated and characterised. In addition a rare natural chromanone (6,7-dimethoxy-4-chromanone) and the known rotenoids rotenone, tephrosin and dehydrodeguelin were identified. The structures were assigned on the basis of spectroscopic evidence. The larvicidal activity of the crude extract is mainly due to rotenone. (c) 2006 Elsevier Ltd. All rights reserved
Y1  - 2006
UR  - http://www.sciencedirect.com/science/article/pii/S0031942206000045
U6  - https://doi.org/10.1016/j.phytochem.2006.01.002
ER  - 
TY  - JOUR
A1  - Yenesew, Abiy
A1  - Midiwo, Jacob O.
A1  - Guchu, S. M.
A1  - Heydenreich, Matthias
A1  - Peter, Martin G.
T1  - Three iosoflav-3-enes and a 2-arylbenzofuran from the root bark of Erythrina burttii
N2  - From the root bark of Erythrina burttii three new isoflav-3-enes, 7,4'-dihydroxy-2'-methoxy-6- (1'',1''-dimethylallyl)isoflav-3-ene (trivial name, burttinol-A), 4'-hydroxy-2'- methoxy-(2'',2''-dimethylpyrano[5'',6'':8,7]isoflav-3-ene (trivial name, burttinol-B), 7,4'-dihydroxy-2'-methoxy-8-(3'',3''-dimethylallyl)isoflav-3-ene (trivial name, burttinol-C), and a new 2-arylbenzofuran, 6,4'-dihydroxy-2'-methoxy-5- (1'',1''-dimethylallyl)-2-arylbenzofuran (trivial name, burttinol-D) were isolated. In addition, the known compounds, abyssinone V-4'-methyl ether, bidwillol A, calopocarpin, erybraedin A, erythrabyssin II, isobavachalcone, phaseollidin and phaseollin were identified. The structures were determined on the basis of spectroscopic evidence.
Y1  - 2002
ER  - 
TY  - JOUR
A1  - Yenesew, Abiy
A1  - Mushibe, E. K.
A1  - Induli, M.
A1  - Derese, Solomon
A1  - Midiwo, Jacob O.
A1  - Kabaru, Jacques M.
A1  - Heydenreich, Matthias
A1  - Koch, Andreas
A1  - Peter, Martin G.
T1  - 7a-O-methyldeguelol, a modified rotenoid with an open ring-C, from the roots of Derris trifoloata
N2  - From the acetone extract of the roots of Derris trifoliata an isollavonoid derivative, named 7a-O- methyldeguelol, a modified rotenoid with an open ring-C, representing a new sub-class of isollavonoids (the sub-class is here named as rotenoloid), was isolated and characterised. In addition, the known rotenoids, rotenone, deguelin and alpha-toxicarol, were identified. The structures were determined on the basis of spectroscopic evidence. Rotenone and deguelin were identified as the larvicidal principles of the acetone extract of the roots of Derris trifoliata. (c) 2005 Elsevier Ltd. All rights reserved
Y1  - 2005
SN  - 0031-9422
ER  - 
TY  - JOUR
A1  - Yenesew, Abiy
A1  - Irungu, Beatrice
A1  - Derese, Solomon
A1  - Midiwo, Jacob O.
A1  - Heydenreich, Matthias
A1  - Peter, Martin G.
T1  - Two prenylated flavonoids from the stem bark of Erythrina burttii
N2  - From the stem bark of Erythrina burttii, a new isoflavone, 5,2',4'-trihydroxy-7-methoxy-6-(3- methylbut-2-enyl)isoflavone (trivial name, 7-O-methylluteone) and a new flavanone, 5,7-dihydroxy-4'-methoxy- 3'-(3-methylbutadienyl)-5'-(3-methylbut-2-enyl)flavanone (trivial name, burttinonedehydrate) along with three known isoflavonoids (8-prenylluteone, 3-O-methylcalopocarpin and genistein) were isolated. The structures were detd. on the basis of spectroscopic evidence.
Y1  - 2003
ER  - 
TY  - JOUR
A1  - Yenesew, Abiy
A1  - Derese, Solomon
A1  - Midiwo, Jacob O.
A1  - Bii, Christine C.
A1  - Heydenreich, Matthias
A1  - Peter, Martin G.
T1  - Antimicrobial flavonoids from the stem bark of Erythrina burttii
N2  - The chloroform extract of the stem bark of Erythrina burttii showed antifungal and antibacterial activities using the disk diffusion method. Flavonoids were identified as the active principles. Activities were observed against fungi and Gram(+) bacteria, but the Gram(-) bacteria Escherichia coli was resistant. (c) 2005 Elsevier B.V. All rights reserved
Y1  - 2005
SN  - 0367-326X
ER  - 
TY  - THES
A1  - Derese, Solomon
A1  - Yenesew, Abiy
A1  - Midiwo, Jacob O.
A1  - Heydenreich, Matthias
A1  - Peter, Martin G.
T1  - A new isoflavone from stem bark of Millettia dura
Y1  - 2003
SN  - 1011-3924
ER  - 
TY  - JOUR
A1  - Yenesew, Abiy
A1  - Midiwo, Jacob O.
A1  - Meisner, M.
A1  - Heydenreich, Matthias
A1  - Peter, Martin G.
T1  - Two prenylated flavanones from stem bark of erythrina burttii
Y1  - 1998
ER  - 
TY  - JOUR
A1  - Yenesew, Abiy
A1  - Midiwo, Jacob O.
A1  - Heydenreich, Matthias
A1  - Peter, Martin G.
T1  - Four isoflavanones from stem bark of erythrina sacleuxii
Y1  - 1998
ER  - 
TY  - GEN
A1  - Bringmann, Gerhard
A1  - Mutanyatta-Comar, Joan
A1  - Maksimenka, Katja
A1  - Wanjohi, John M.
A1  - Heydenreich, Matthias
A1  - Brun, Reto
A1  - Müller, Werner E. G.
A1  - Peter, Martin
A1  - Midiwo, Jacob O.
A1  - Yenesew, Abiy
T1  - Joziknipholones A and B : the First Dimeric Phenylanthraquinones, from the Roots of Bulbine frutescens
N2  - 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.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - paper 104 
KW  - antimalarial activity
KW  - chirality
KW  - joziknipholones
KW  - natural products
KW  - structure elucidation
Y1  - 2008
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-42638
ER  - 
TY  - GEN
A1  - Peter, Martin G.
T1  - Chemische Modifikation von Biopolymeren durch Chinone und Chinonmethide
N2  - Chinone und Vorstufen, die oxidativ in Chinone und/oder Chinonmethide umgewandelt werden können, sind in der Natur weit verbreitet. Als sekundäre Naturstoffe wirken sie häufig antibiotisch, cytotoxisch, aber auch pathogen, und eine Reihe von Pflanzen und Tieren benutzt chinoide Substanzen als Abwehrstoffe, oft mit spektakulärem Erfolg. Auf makromolekularer Ebene spielen Chinonmethide im Pflanzenreich eine Schlüsselrolle bei der Biosynthese von Lignin, während die Bildung von Melanoproteinen ein Beispiel für Reaktionen von o-Chinonen im Tierreich ist. Bei den Insekten dienen Chinone und Chinonmethide zur Bildung des lebensnotwendigen Exoskeletts. Die Reaktivität von Chinonen in biologischen Systemen hat auch für den Menschen unmittelbare Bedeutung in pharmazeutischer, toxikologischer und technologischer Hinsicht. Den Beispielen in diesem Aufsatz liegt ein gemeinsames Prinzip zugrunde, nämlich die chemische Modifikation von Biopolymeren durch Chinone und Chinonmethide. Wie sich besonders bei einer detaillierteren Betrachtung der Reaktionen zeigt, die zur Sklerotisierung der Insektencuticula führen, sind in den letzten Jahren wichtige neue Erkenntnisse hinzugekommen, die vor allem durch die modernen Methoden der Stofftrennung und der Festkörper-NMR-Spektroskopie ermöglicht worden sind.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - paper 043 
Y1  - 1989
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-16802
ER  -