• Biosynthesis of the repeating units of the exopolysaccharides amylovoran from Erwinia amylovora and stewartan from Pantoea stewartii

      Langlotz, Christine; Schollmeyer, Martin; Coplin, David L.; Nimtz, Manfred; Geider, Klaus; Max-Planck-Institute for Cell Biology, Ladenburg, Germany (2012-06-27)
    • Isolation, characterisation and molecular imaging of a high-molecular-weight insect biliprotein, a member of the hexameric arylphorin protein family.

      Kayser, Hartmut; Mann, Karlheinz; Machaidze, Gia; Nimtz, Manfred; Ringler, Philippe; Müller, Shirley A; Aebi, Ueli; Institut für Allgemeine Zoologie und Endokrinologie, Universität Ulm, Germany. hartmut.kayser@uni-ulm.de (2009-05-29)
      The abundant blue hemolymph protein of the last instar larvae of the moth Cerura vinula was purified and characterized by protein-analytical, spectroscopic and electron microscopic methods. Amino acid sequences obtained from a large number of cleavage peptides revealed a high level of similarity of the blue protein with arylphorins from a number of other moth species. In particular, there is a high abundance of the aromatic amino acids tyrosine and phenylalanine amounting to about 19% of total amino acids and a low content of methionine (0.8%) in the Cerura protein. The mass of the native protein complex was studied by size-exclusion chromatography, analytical ultracentrifugation, dynamic light scattering and scanning transmission electron microscopy and found to be around 500 kDa. Denaturating gel electrophoresis and mass spectrometry suggested the presence of two proteins with masses of about 85 kDa. The native Cerura protein is, therefore, a hexameric complex of two different subunits of similar size, as is known for arylphorins. The protein was further characterized as a weakly acidic (pI approximately 5.5) glycoprotein containing mannose, glucose and N-acetylglucosamine in an approximate ratio of 10:1:1. The structure proposed for the most abundant oligosaccharide of the Cerura arylphorin was the same as already identified in arylphorins from other moths. The intense blue colour of the Cerura protein is due to non-covalent association with a bilin of novel structure at an estimated protein subunit-to-ligand ratio of 3:1. Transmission electron microscopy of the biliprotein showed single particles of cylindrical shape measuring about 13 nm in diameter and 9 nm in height. A small fraction of particles of the same diameter but half the height was likely a trimeric arylphorin dissociation intermediate. Preliminary three-dimensional reconstruction based on averaged transmission electron microscopy projections of the individual particles revealed a double-trimeric structure for the hexameric Cerura biliprotein complex, suggesting it to be a dimer of trimers.
    • Kinome analysis of receptor-induced phosphorylation in human natural killer cells.

      König, Sebastian; Nimtz, Manfred; Scheiter, Maxi; Ljunggren, Hans-Gustaf; Bryceson, Yenan T; Jänsch, Lothar; Department of Molecular Structural Biology, Helmholtz-Zentrum für Infektionsforschung, Braunschweig, Germany. (2012)
      Natural killer (NK) cells contribute to the defense against infected and transformed cells through the engagement of multiple germline-encoded activation receptors. Stimulation of the Fc receptor CD16 alone is sufficient for NK cell activation, whereas other receptors, such as 2B4 (CD244) and DNAM-1 (CD226), act synergistically. After receptor engagement, protein kinases play a major role in signaling networks controlling NK cell effector functions. However, it has not been characterized systematically which of all kinases encoded by the human genome (kinome) are involved in NK cell activation.
    • Mechanistic studies on cationic ring-opening polymerisation of cyclodextrin derivatives using various Lewis acids

      Bösch, Andreas; Nimtz, Manfred; Mischnik, Petra (Springer Science+Business Media B.V., 2007-06-19)
    • Nonomuraea rosea sp. nov.

      Kämpfer, Peter; Busse, Hans-Jürgen; Tindall, Brian J; Nimtz, Manfred; Grün-Wollny, Iris; Institut für Angewandte Mikrobiologie, Justus-Liebig-Universität Giessen, D-35392 Giessen, Germany. peter.kaempfer@umwelt.uni-giessen.de (2010-05)
      A Gram-positively staining, aerobic, non-motile actinomycete, strain GW 12687(T), that formed rose-pigmented colonies and branched substrate and aerial mycelia was studied in detail for its taxonomic position. On the basis of 16S rRNA gene sequence similarity studies, strain GW 12687(T) was grouped into the genus Nonomuraea, being most closely related to Nonomuraea dietziae (97.6 %), Nonomuraea africana (97.1 %), and Nonomuraea kuesteri (97.1 %). The 16S rRNA gene sequence similarity to other species of the genus Nonomuraea was < or =97 %. The chemotaxonomic characterization supported allocation of the strain to the genus Nonomuraea. The major menaquinone was MK-9(H(4)) with minor amounts of MK-9(H(2)), MK-9(H(6)), MK-9(H(0)) and MK-8(H(4)). The polar lipid profile contained the major compound diphosphatidylglycerol, moderate amounts of phosphatidylmonomethylethanolamine, phosphatidylethanolamine, hydroxy-phosphatidylethanolamine, hydroxy-phosphatidylmonomethylethanolamine, and an unknown aminophosphoglycolipid. Phosphatidylinositol mannosides and phosphatidylinositol were also present. The major fatty acids were iso- and anteiso- and 10-methyl-branched fatty acids. The results of physiological and biochemical tests allowed genotypic and phenotypic differentiation of strain GW 12687(T) from closely related species. Thus, GW 12687(T) represents a novel species of the genus Nonomuraea, for which the name Nonomuraea rosea sp. nov. is proposed, with GW 12687(T) (=DSM 45177(T) =CCUG 56107(T)) as the type strain.
    • PfaH2: A novel hydrophobin from the ascomycete Paecilomyces farinosus.

      Zelena, Katerina; Takenberg, Meike; Lunkenbein, Stefan; Woche, Susanne K; Nimtz, Manfred; Berger, Ralf G; Naturwissenschaftliche Fakultät der Leibniz Universität Hannover, Institut für Lebensmittelchemie, Hannover, Germany. (2013-03)
      The pfah2 gene coding for a novel hydrophobin PfaH2 from the ascomycete Paecilomyces farinosus was identified during sequencing of random clones from a cDNA library. The corresponding protein sequence of PfaH2 deduced from the cDNA comprised 134 amino acids (aa). A 16 aa signal sequence preceded the N-terminus of the mature protein. PfaH2 belonged to the class Ia hydrophobins. The protein was isolated using trifluoroacetic acid extraction and purified via SDS-PAGE and high-performance liquid chromatography. The surface activity of the recently described PfaH1 and of PfaH2 was compared by the determination of contact angles (CAs) on glass slides and Teflon tape, and the CA of distilled water droplets was measured on glass slides coated with hydrophobin PfaH1 or PfaH2. Surprisingly, both hydrophobins adsorbed to hydrophilic surfaces and changed their physicochemical properties to a similar quantitative extent, although little aa sequence homology was found.
    • Production of Cellulose and Curli Fimbriae by Members of the Family Enterobacteriaceae Isolated from the Human Gastrointestinal Tract

      Zogaj, Xhavit; Bokranz, Werner; Nimtz, Manfred; Römling, Ute (American Society for Microbiology, 2003-07)
    • Saliva proteins of vector Culicoides modify structure and infectivity of bluetongue virus particles.

      Darpel, Karin E; Langner, Kathrin F A; Nimtz, Manfred; Anthony, Simon J; Brownlie, Joe; Takamatsu, Haru-Hisa; Mellor, Philip S; Mertens, Peter P C; Pirbright Laboratory, Vector-borne Disease Programme, Institute for Animal Health, Woking, United Kingdom. karin.darpel@bbsrc.ac.uk (2011)
      Bluetongue virus (BTV) and epizootic haemorrhagic disease virus (EHDV) are related orbiviruses, transmitted between their ruminant hosts primarily by certain haematophagous midge vectors (Culicoides spp.). The larger of the BTV outer-capsid proteins, 'VP2', can be cleaved by proteases (including trypsin or chymotrypsin), forming infectious subviral particles (ISVP) which have enhanced infectivity for adult Culicoides, or KC cells (a cell-line derived from C. sonorensis). We demonstrate that VP2 present on purified virus particles from 3 different BTV strains can also be cleaved by treatment with saliva from adult Culicoides. The saliva proteins from C. sonorensis (a competent BTV vector), cleaved BTV-VP2 more efficiently than those from C. nubeculosus (a less competent/non-vector species). Electrophoresis and mass spectrometry identified a trypsin-like protease in C. sonorensis saliva, which was significantly reduced or absent from C. nubeculosus saliva. Incubating purified BTV-1 with C. sonorensis saliva proteins also increased their infectivity for KC cells ∼10 fold, while infectivity for BHK cells was reduced by 2-6 fold. Treatment of an 'eastern' strain of EHDV-2 with saliva proteins of either C. sonorensis or C. nubeculosus cleaved VP2, but a 'western' strain of EHDV-2 remained unmodified. These results indicate that temperature, strain of virus and protein composition of Culicoides saliva (particularly its protease content which is dependent upon vector species), can all play a significant role in the efficiency of VP2 cleavage, influencing virus infectivity. Saliva of several other arthropod species has previously been shown to increase transmission, infectivity and virulence of certain arboviruses, by modulating and/or suppressing the mammalian immune response. The findings presented here, however, demonstrate a novel mechanism by which proteases in Culicoides saliva can also directly modify the orbivirus particle structure, leading to increased infectivity specifically for Culicoides cells and, in turn, efficiency of transmission to the insect vector.
    • Structural characterization of the exopolysaccharide PS-EDIV from Sphingomonas pituitosa strain DSM 13101.

      Schultheis, Ellen; Dreger, Michael A; Nimtz, Manfred; Wray, Victor; Hempel, Dietmar C; Nörtemann, Bernd; Institute of Biochemical Engineering, Technical University of Braunschweig, Braunschweig, Germany. (2008-04)
      Members of the bacterial genus Sphingomonas are known to produce highly viscous polysaccharides in solution. The exopolysaccharide PS-EDIV was produced by Sphingomonas pituitosa strain DSM 13101, purified using centrifugation, and precipitation and its structure was elucidated by 1D and 2D NMR techniques and chemical microderivatization combined with various mass spectrometric techniques. The following repeating unit of the polysaccharide could be identified: [formula: see text]. In addition, the polysaccharide also contains acetyl and glyceryl groups whose exact positions were not determined. PS-EDIV is similar in structure to a known exopolysaccharide but differs in being the first bacterial polysaccharide in which two different glucuronic acids are combined. It caused a high viscosity of the culture broth after cultivation for 48 h, although a gelation was not observed.
    • Total synthesis and biological evaluation of (-)-pectinatone employing a methyl-branched wax ester as key building block.

      Galeyeva, Yana; Helbig, Sarah; Morr, Michael; Sasse, Florenz; Nimtz, Manfred; Laschat, Sabine; Baro, Angelika; Institut für Organische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart. (2006-08)
      Unnatural (-)-pectinatone ((-)-3) was prepared in five steps starting from the highly methyl-branched wax ester 4, employing bromination of the ester enolate and subsequent base-induced elimination to the enoate 6 as the key step. Both (-)-3 and the amides 8b and 8c, which were isolated as by-products in the reaction sequence, displayed antimicrobial activity and cytotoxicity.