Zur Flora der Petzenalpe in Kärnthen

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Influence of growth conditions on physicochemical surface characteristics of two gramnegative and two grampositive bacteria

Summary The focus of this work was the investigation of correlations between cultivation parameters and cell surface physicochemistry (hydrophobicity, electrophoretic mobility, isoelectric point) of four strains (Pseudomonas aeruginosa DSM 1253, Escherichia coli 72, Arthrobacter oxydans DSM 420 and Corynebacterium glutamicum DSM 20300).Abbreviations EPM electrophoretic mobility Dedicated to Prof. Dr. Joachim Klein for his 60th birthday     

Biological and Abiological Sulfur Reduction at High Temperatures

Reduction of elemental sulfur was studied in the presence and absencè of thermophilic sulfur-reducing bacteria, at temperatures ranging from 65 to 110°C, in anoxic artificial seawater media. Above 80°C, significant amounts of sulfide were produced abiologically at linear rates, presumably by the disproportionation of sulfur. These rates increased with increasing temperature and pH and were enhanced by yeast extract. In the same medium, the sulfur respiration of two recent thermophilic isolates, a eubacterium and an archaebacterium, resulted in sulfide production at exponential rates. Although not essential for growth, sulfur increased the cell yield in both strains up to fourfold. It is suggested that sulfur respiration is favored at high temperatures and that this process is not limited to archaebacteria, but is shared by other extreme thermophiles.     

Histochemical demonstration of carbonic anhydrase activity

Summary Freeze-dried frozen sections are floated on the surface of the freshly prepared incubation mixture (CoSO₄ 1.75 × 10^–3 M, H₂SO₄ 5.3 × 10^–2 M, NaHCO₃ 1.57 × 10^–2 M and KH₂PO₄ 1.17 to 11.7 × 10^–3 M; demonstration of weak activity requires high phosphate). A compound containing cobalt and phosphorous precipitates at carbonic anhydrase sites and is converted to CoS. Adequate staining requires only 2–10 minutes of incubation. Actazolamide inhibits the staining reaction in specific concentrations. Actazolamidein vivo, 20 mg/kgi.v. to mice 30 minutes before sacrifice also inhibited the staining. The proportion phosphorous in the specific precipitate increases with KH₂PO₄ of the medium (shown by the addition of⁶⁰Co and³²P). An explanation of the reaction mechanism is given, based on the catalyzed loss of CO₂ in the surface layer. The inclusion of phosphate in the medium makes this modification ofHäusler's method so sensitive that it shows carbonic anhydrase activity in for instance stratum spinosum of the skin.This investigation was supported by grants from the Medical Faculty, University of Uppsala and from the U.S. National Institutes of Health (Grant NB 3060 to E.Bárány).     

Beitrag zur Theorie des Chromomerenaustausches

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A Swedish comment on ‘review: the availability of life-cycle studies in Sweden’

The International Journal of Life Cycle Assessment -