In the favoured core-accretion model of formation of planetary systems, solid planetesimals accumulate to build up planetary cores, which then accrete nebular gas if they are sufficiently massive. Around M-dwarf stars ( the most common stars in our Galaxy), this model favours the formation of Earth-mass (M+) to Neptune-mass planets with orbital radii of 1 to 10 astronomical units (AU), which is consistent with the small number of gas giant planets known to orbit M-dwarf host stars(1-4). More than 170 extrasolar planets have been discovered with a wide range of masses and orbital periods, but planets of Neptune's mass or less have not hitherto been detected at separations of more than 0.15 AU from normal stars. Here we report the discovery of a 5.5(-2.7)(+5.5)M(+) planetary companion at a separation of 2.6(- 0.6)(+1.5) AU from a 0.22(-0.11)(+0.21)M(.) M-dwarf star, where M-. refers to a solar mass. (We propose to name it OGLE- 2005-BLG-390Lb, indicating a planetary mass companion to the lens star of the microlensing event.) The mass is lower than that of GJ876d (ref. 5), although the error bars overlap. Our detection suggests that such cool, sub-Neptune-mass planets may be more common than gas giant planets, as predicted by the core accretion theory.
Inhalt: AUFSÄTZE Martin Winter „Der Untertan auf Posten“ - Deserteursverfolgung an der brandenburgisch-mecklenburgischen Grenze im 18. Jahrhundert Jan Willem Huntebrinker Geordneter Sozialverband oder Gegenordnung? Zwei Perspektiven auf das Militär im 16. und 17. Jahrhundert Ulrike Ludwig Strafverfolgung und Gnadenpraxis in Kursachsen unter dem Eindruck des Dreißigjährigen Krieges Heinrich Lang Der „zivile“ Krieg. Ordnungskonzepte zwischen städtischer Gesellschaft und Söldnerführern im Italien der Renaissance PROJEKTE Martin Meier „Zur Rolle des Militärs in der utopischen Literatur und im utopischen Denken der frühen Neuzeit“ (16.-18. Jahrhundert) Nicolas Disch „Lust am Krieg“? - Engelberger Talleute in Solddiensten (1600-1800) BERICHTE Protokoll der Mitgliederversammlung des Arbeitskreises „Militär und Gesellschaft in der Frühen Neuzeit“ e.V. (AMG) am 21. September 2006 (Konstanz) Urte Evert „Die Rückkehr der Condottieri? Krieg und Militär im Spannungsfeld zwischen Verstaatlichung und Privatisierung. Die Entwicklung vom 16. Jahrhundert bis zur Gegenwart.“, 12. bis 14. Mai 2006 (Potsdam) Elizabeth Harding und Christine D. Schmidt „Vormoderne Konfliktbewältigung aus regionalgeschichtlicher Perspektive“, 21. und 22. Juni 2006 (Münster) Jan Willem Huntebrinker „Kriegs-Bilder“: Epochenübergreifende Sektion des 46. Deutschen Historikertags, 20. September 2006(Konstanz) REZENSIONEN Dorit Schneider Gabriele Jochums (Bearb.), Bibliographie Friedrich Wilhelm I.: Schrifttum von 1688 bis 2005, Berlin 2005 ANKÜNDIGUNGEN Militär und Recht in der Frühen Neuzeit, 4.-7. Oktober 2007 auf Schloss Thurnau bei Bayreuth Markus Pöhlmann Anonyme und pseudonyme Militärliteratur
The nature of the periplastidial pathway of starch biosynthesis was investigated with the model cryptophyte Guillardia theta. The storage polysaccharide granules were shown to be composed of both amylose and amylopectin fractions with a chain length distribution and crystalline organization very similar to those of starch from green algae and land plants. Most starch granules displayed a shape consistent with biosynthesis occurring around the pyrenoid through the rhodoplast membranes. A protein with significant similarity to the amylose-synthesizing granule-bound starch syntbase 1 from green plants was found as the major polypeptide bound to the polysaccharide matrix. N-terminal sequencing of the mature protein proved that the precursor protein carries a nonfunctional transit peptide in its bipartite topogenic signal sequence which is cleaved without yielding transport of the enzyme across the two inner plastid membranes. The enzyme was shown to display similar affinities for ADP and UDP-glucose, while the V-max measured with UDP-glucose was twofold higher. The granule-bound starch synthase from Guillardia theta was demonstrated to be responsible for the synthesis of long glucan chains and therefore to be the functional equivalent of the amylose- synthesizing enzyme of green plants. Preliminary characterization of the starch pathway suggests that Guillardia theta utilizes a UDP-glucose-based pathway to synthesize starch