The IPB has once again been recognized for its exemplary actions in terms of equal opportunity-oriented personnel and organizational policies and has received the TOTAL E-QUALITY certification for the…
The Plant Science Student Conference (PSSC) has been organised by students from the two Leibniz institutes, IPK and IPB, every year for the last 20 years. In this interview, Christina Wäsch (IPK) and…
Fruiting bodies of the Chilean mushroom Dermocybe nahuelbutenis Garrido & E. Horak (syn.: Cortinariusnahuelbutensis (Garrido & E. Horak) E. Valenz. & G. Moreno) were chemically investigated for the first time andafforded the new dimeric anthraqinone 7,7'-emodinphyscion (1) beside the know anthraquinones dermolutein (2),endocrocin (3), skyrin (4) and the dimeric pre-anthraquinone derivative flavomannin C (5). The chemotaxonomicsignificance of the pigments is discussed.
Publications
Alresly, Z.; Lindequist, U.; Lalk, M.; Porzel, A.; Arnold, N.; Wessjohann, L. A.;Bioactive Triterpenes from the Fungus Piptoporus betulinusRec. Nat. Prod.10103-108(2016)
Phytochemical investigation of the ethyl acetate extract of the fruiting bodies from the basidiomycete Piptoporus betulinus led to the isolation of a new bioactive lanostane triterpene identified as 3 b -acetoxy-16-hydroxy-24-oxo-5α-lanosta-8- ene-21-oic acid (1). In addition, ten known triterpenes, polyporenic acid A (5), polyporenic acid C (4), three derivatives of polyporenic acid A (8, 10, 11), betulinic acid (3), betulin (2), ergosterol peroxide (6), 9,11-dehydroergosterol peroxide (7), and fomefficinic acid (9), were also isolated from the fungus. All isolated compounds were tested for antimicrobial activity against some Gram-positive and Gram-negative bacteria as well as against a fungal strain. The new triterpene and some of the other compounds showed antimicrobial activity against Gram-positive bacteria.
Publications
Rausch, F.; Schicht, M.; Bräuer, L.; Paulsen, F.; Brandt, W.;Protein modeling and molecular dynamics simulation of the two novel surfactant proteins SP-G and SP-HJ. Mol. Model.202513(2014)DOI: 10.1007/s00894-014-2513-0
Surfactant proteins are well known from the human lung where they are responsible for the stability and flexibility of the pulmonary surfactant system. They are able to influence the surface tension of the gas–liquid interface specifically by directly interacting with single lipids. This work describes the generation of reliable protein structure models to support the experimental characterization of two novel putative surfactant proteins called SP-G and SP-H. The obtained protein models were complemented by predicted posttranslational modifications and placed in a lipid model system mimicking the pulmonary surface. Molecular dynamics simulations of these protein-lipid systems showed the stability of the protein models and the formation of interactions between protein surface and lipid head groups on an atomic scale. Thereby, interaction interface and strength seem to be dependent on orientation and posttranslational modification of the protein. The here presented modeling was fundamental for experimental localization studies and the simulations showed that SP-G and SP-H are theoretically able to interact with lipid systems and thus are members of the surfactant protein family.
Publications
Ali, N. A. A.; Wurster, M.; Arnold, N.; Lindequist, U.; Wessjohann, L.;Essential Oil Composition from Oleogum Resin of Soqotraen Commiphora kuaRec. Nat. Prod.270-75(2008)
The major constituents of the essential oil obtained by hydrodistillation from the oleogum resin of Commiphora kua Vollesen were identified by GC-MS. Sixteen constituents were detected from the essential oil, which constituted about (90.5%) of the total amount. Major constituents of the oil were α- cadinol (33.0%), g -cadinene (22.5%), d -cadinene (17.0%), isocaryophyllene (3.7%), allo-aromadendrene (2.8%), α-muurolene (2.7%), and α-humulene (2.4%). The Oil of Commiphora kua showed moderate antifungal activity against Cladosporium cucumerinum.