• Crystal structure of the electron transfer complex rubredoxin rubredoxin reductase of Pseudomonas aeruginosa.

      Hagelueken, Gregor; Wiehlmann, Lutz; Adams, Thorsten M; Kolmar, Harald; Heinz, Dirk W; Tümmler, Burkhard; Schubert, Wolf-Dieter; Molecular Host-Pathogen Interactions, Division of Structural Biology, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, D-38124 Braunschweig, Germany. (2007-07-24)
      Crude oil spills represent a major ecological threat because of the chemical inertness of the constituent n-alkanes. The Gram-negative bacterium Pseudomonas aeruginosa is one of the few bacterial species able to metabolize such compounds. Three chromosomal genes, rubB, rubA1, and rubA2 coding for an NAD(P)H:rubredoxin reductase (RdxR) and two rubredoxins (Rdxs) are indispensable for this ability. They constitute an electron transport (ET) pathway that shuttles reducing equivalents from carbon metabolism to the membrane-bound alkane hydroxylases AlkB1 and AlkB2. The RdxR-Rdx system also is crucial as part of the oxidative stress response in archaea or anaerobic bacteria. The redox couple has been analyzed in detail as a model system for ET processes. We have solved the structure of RdxR of P. aeruginosa both alone and in complex with Rdx, without the need for cross-linking, and both structures were refined at 2.40- and 2.45-A resolution, respectively. RdxR consists of two cofactor-binding domains and a C-terminal domain essential for the specific recognition of Rdx. Only a small number of direct interactions govern mutual recognition of RdxR and Rdx, corroborating the transient nature of the complex. The shortest distance between the redox centers is observed to be 6.2 A.
    • 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.
    • Metabolic peculiarities of Aspergillus niger disclosed by comparative metabolic genomics.

      Sun, Jibin; Lu, Xin; Rinas, Ursula; Zeng, An Ping; Helmholtz Centre for infection research, Inhoffenstr. 7, D-38124 Braunschweig, Germany. (2007)
      Aspergillus niger is an important industrial microorganism for the production of both metabolites, such as citric acid, and proteins, such as fungal enzymes or heterologous proteins. Despite its extensive industrial applications, the genetic inventory of this fungus is only partially understood. The recently released genome sequence opens a new horizon for both scientific studies and biotechnological applications.
    • 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.