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doi: 10.1007/BF00417127pmid: N/A
203 71 71 4 4 Jolly H. Galt Howard C. Whisler Friday Harbor Laboratories, Dept. of Botany University of Washington Friday Harbor Wa. USA Summary Thalassomyces marsupii , an ellobiopsid parasite of the pelagic amphipod Parathemisto pacifica , produces biflagellate swarmers following simultaneous cleavage of the gonomere. One flagellum is directed posteriorly, the other circumferentially. The vegetative thallus is bounded by a complex pellicle and not a cell wall. Our observations suggest that Thalassomyces is a member of the achlorophyllous Dinophyceae.
doi: 10.1007/BF00417128pmid: N/A
203 71 71 4 4 S. Mann Hygiene-Institut der Universität Bonn Bonn Deutschland Summary The chloroform soluble pigments of Pseudomonas aureofaciens and P. iodina have been isolated chromatographically and identified by means of synthetic reference substances. A specific color reaction is developed by 2-hydroxyphenazine after treatment with ammonia and formaldehyde. The electrochemical properties of phenazine-1-carboxylic acid, 2-hydroxyphenazine and iodinin are studied by means of direct current polarography. A simultaneous determination of both phenazine-1-carboxylic acid and 2-hydroxyphenazine in the evaporated chloroform extract of Pseudomonas aureofaciens has been performed in alcaline phosphate buffer using the method of derivative polarography. Comparative studies of the half wave potentials allow conclusions on the function of the pigments as redox catalysts.
doi: 10.1007/BF00417129pmid: 4316972
203 71 71 4 4 T. Peeters M. I. H. Aleem Thomas-Hunt Morgan School of Biological Sciences, Department of Microbiology University of Kentucky Lexington Kentucky USA Summary Intact cells of Thiobacillus denitrificans catalyzed the oxidation of thiosulfate, sulfide and sulfite with nitrate or oxygen as the terminal acceptor. The anaerobic oxidation of thiosulfate, sulfide and sulfite was sensitive to the inhibitors of the flavoprotein system. Under aerobic conditions the oxidation of sulfide and sulfite was sensitive to these inhibitors but the thiosulfate oxidation was unaffected. Cyanide and azide inhibited the aerobic and anaerobic respiration when thiosulfate, sulfide or sulfite served as electron donors. The oxidation of thiosulfate by cell-free preparations was mediated by cytochromes of c, a and o -types. The cell-free extracts also catalyzed the oxidation of NADH and succinate, involving flavoproteins and b, c, a and o -type cytochromes. In addition, a cytochrome oxidase sensitive to cyanide and azide was also present.
doi: 10.1007/BF00417130pmid: N/A
203 71 71 4 4 Hans Bender Chemisches Laboratorium der Universität Freiburg i.Br. Freiburg i. Br. Deutschland Summary Experiments performed in our laboratory point at an association of cell-bound pullulanase (bacterial R-enzyme E.C.3.2.1.9) with the outer membrane of continuously cultivated cells of Aerobacter aerogenes . 1. Nearly all of the pullulanase activity is bound to the cell wall fraction, obtained by short-time sonification of continuously grown cells and fractionation of the cell components. From the walls the enzyme can be extracted with sodium dodecylsulphate, it is shown to be associated with a phospholipid-protein, insoluble at a pH value of 5.0 (26% phospholipid, 13.1 pullulanase units per mg protein). 2. Alternate freezings and thawings of continuously cultivated cells in hypertonic environment liberate about 40% of the cell-bound pullulanase. The enzyme found in the supernatant is associated with a lipopolysaccharide-phospholipid-protein, sedimentable at 130,000xg (62.4% lipopolysaccharide, 33 pullulanase units per mg protein). 3. 90% of cell-bound pullulanase become cell-free within three hours, if continuously grown cells are allowed to grow batchwise in the presence of chloramphenicol (1 μg/ml) or streptomycin (5 μg/ml). Besides “free” pullulanase, larger amounts of lipopolysaccharide-phospholipid-protein can be detected in the culture filtrate of the cells treated with the antibiotics. The lipopolysaccharide-phospholipid-protein released contains less protein than that extractable by freezing and thawing the cells in hypertonic environment. The composition of the lipopolysaccharide moieties of both the components seems, however, to be quite similar.
doi: 10.1007/BF00417131pmid: 5428606
203 71 71 4 4 R. Reistad Department of Biochemistry, Norway Institute of Technology University of Trondheim Trondheim Norway Department of Microbiology, Dental Faculty University of Oslo Blindern Oslo 3 Norway Dept. of Microbiology Dental Fac. University of Oslo Blindern Oslo 3 Norway Summary Comparative studies have been carried out on the amino acid composition of the bulk protein of the two main types of extremely halophilic bacteria and their non-halophilic, bacteriological counterparts. The protein of all the extreme halophiles tested was relatively high in aspartic and glutamic acids and low in lysine and alanine. The results have furnished a basis for a discussion of the molecular mechanisms which might be involved in the evolution of an extremely halophilic organism from a non-halophilic organism.
doi: 10.1007/BF00417132pmid: N/A
203 71 71 4 4 M. Chippaux F. Pichinoty Laboratoire de Chimie Bactérienne Centre National de la Recherche Scientifique Marseille France Summary Nitrate reductase A: In anaerobic cultures of several Enterobacteriaceae on a complex medium without NO 3 - , the biosynthesis of enzyme A is induced by 5.88·10 -3 M nitrite or by 10 -4 M azide. In the case of several bacteria, the activity of extracts of cultures induced by both NO 3 - and N 3 - is higher than that of extracts of cultures induced by only one of these 2 compounds. Nitrate reductase B: 10 -4 M azide does not induce the biosynthesis of enzyme B in the 3 bacteria studied.
doi: 10.1007/BF00417133pmid: N/A
203 71 71 4 4 Werner Wehrmeyer Botanisches Institut der Universität Marburg Summary The ultrastructure of the chloroplasts and pyrenoids of each one species of the genera Cryptomonas, Chroomonas , and Hemiselmis (Cryptophyceae) was investigated by electron microscopy. The thylakoids are loosely associated mainly in pairs, separated by a slight space of 30–80 Å. One thylakoid can be associated with one and the same thylakoid for a longer distance or in alternation with two thylakoids on opposite sides. Bifurcated thylakoids were observed in all three species. Deviating from all known chloroplasts the thylakoids of the Cryptophyceae, investigated here, are electron opaque, containing a fine granular, dense material, dispersed in the intrathylakoidal space (=loculus in the terminology of Weier, 1962). Caused by a varying distribution of the intrathylakoidal material the thickness of the thylakoids changes in the range of 190–300 Å in Cryptomonas and of 240 to 360 Å in Hemiselmis and Chroomonas ; club-shaped parts at the end of the thylakoids can even exceed these values. Ribosome-like particles, 120–180 Å in diameter, vacuoles, and scattered electron-transparent DNA-containing areas were observed in the chloroplast matrix, but no granular fraction corresponding to the biliprotein particles of the Rhodophyceae or Cyanophyceae associated with the surface of the thylakoid membranes could be detected. The stalked pyrenoids of Hemiselmis and Chroomonas are bulging of the anterior end of the boat-shaped chloroplast traversed by two associated thylakoids. In Cryptomonas the pyrenoid occupies the central part of the H- or U-shaped chloroplast, thus being a part of the connection of the two lobes. Paired thylakoids penetrate the bridge and terminate in the pyrenoid basis. On its free face the pyrenoid is bisected by a groove containing the stigma. The pyrenoids are surrounded by starch grains which lie outside the chloroplast envelope, yet, they are enclosed together with the stigma and the whole chloroplast by a periplastidal ER-cisterna, which usually is in continuity with the nuclear envelope.
Schröder, Joachim; Reichenbach, Hans
doi: 10.1007/BF00417134pmid: N/A
203 71 71 4 4 Joachim Schröder Hans Reichenbach Lehrstuhl für Mikrobiologie Biologisches Institut II der Universität Freiburg Freiburg Deutschland Medical School Dept. of Microbiology University of Minnesota 1060 Mayo Memorial Building 55 455 Minneapolis Minn USA Summary 1. The fatty acid composition of Stigmatella aurantiaca does not change significantly during myxospore formation, neither qualitatively nor quantitatively. The cells contain 60–70 μg of fatty acids per mg cell protein, about 40% of which is bound in phospholipids. 2. As main fatty acids were identified: branched C 15:0 , about 35%; and monounsaturated C 16:1 , about 20%. 3. The fatty acid composition of Stigmatella aurantiaca resembles that of other gliding bacteria and bacteria in general, but not that of the blue-green algae.
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