Pseudomonas radiora is an aerobic and heterotrophic organism, but forms bacteriochlorophyll under selected conditions reported in a previous paper. In order to elucidate the relation of P. radiora to the anaerobic and photosynthetic genus Rhodopseudomonas, a chemotaxonomic experiment was conducted. P. radiora formed ubiquinone-10 (Q-10), the straight-chain unsaturated acid of C18:1 as the major component, and phosphatidylcholine, phosphatidylethanolamine, bisphosphatidylglycerol and phosphatidylglycerol, as phospholipids. The guanine plus cytosine content of DNA ranged from 61.5 to 65.9%. From these results, it is suggested that P. radiora is more closely related to Rhodopseudomonas palustris than to the other species in the genus Rhodopseudomonas.
Quantitative changes in amounts of the enzymes governing exchange between free- and phospholipid alcoholic amines in membranes of the soil amoeba Acantharnoeba palestinensis have been produced by manipulation of intracellular pool levels of soluble alcoholic amines. Following growth of cells in media containing 10mM choline, 10mM ethanolamine or 20mM L-serine for 24hr, intracellular pools of these bases were elevated 8-fold, 20-fold and 13-fold greater than normal, respectively. Total cell particulate activities and specific activities of all three exchange enzymes were greatly increased in the presence of elevated choline and greatly decreased in the presence of elevated serine. High ethanolamine pool levels led to increased choline and ethanolamine exchange enzyme amounts with no significant changes detectable in the amount of the serine exchange enzyme. No significant change in total cell lipid phosphorus was observed, indicating a lack of increased phospholipid synthesis. Upon analysis of the rough endoplasmic reticulum, which is one site known to contain the exchange enzymes, a somewhat different pattern than that observed in the total cell particulates emerged. This might have indicated that different changes in the exchange enzymes occurred in yet other cellular membranes where they were localized. In the rough endoplasmic reticulum the specific activities of all three exchange enzymes were greatly enhanced following choline and ethanolamine pool elevations and slightly enhanced following serine pool elevation. In addition, the lipid phosphorus to protein ratio was elevated to varying degrees in the endoplasmic reticulum isolated from the treated cells. The increases in specific activities of the exchange enzymes were positively correlated with the changes in total phospholipid content of the rough endoplasmic reticulum. In choline treated cells, but not the cells with elevated ethanolamine or serine levels, the phosphatidyl choline content was increased about 9% above control levels with corresponding decreases in phosphatidyl ethanolamine and phosphatidyl serine content The data indicate a regulatory interrelationship between soluble intracellular alcoholic amines, exchange enzymes and membrane phospholipids.
Azospirillum brasilense Sp 7 was grown in a nitrogen free medium in a chemostat with malate as the sole carbon source. Several steady states were established. Malate limitation occurred at dilution rates less than 0.05 (hr-1). Maximum growth rate and KS were calculated from Monod's model. Poly-β-hydroxybutyrate content was found to decrease under malate limitation from 18.5% to about 2%. Protein exudation increases under these conditions. The acetylene reduction assay was shown to be not suitable for continuous culture systems. A model for the physiological properties of A. brasilense in a malate limited chemostat is developed.
The relationship between cell morphology and the type of 2, 6-diaminopimelic acid (A2pm) in Kitasatosporia setalba was studied in a submerged culture. When a strain of K. setalba was cultivated in a liquid culture with shaking, it produced two kinds of cells, spore-like cells and filamentous mycelia, which are morphologically distinct from each other. The former contained LL-A2pm, and the latter meso-A2pm. A time course study in a submerged culture inoculated with the spore-like cells demonstrated that each type of A2pm detected in K. setalba is clearly associated with one of the two forms of cell.
A fibre optic nephelometer was evaluated for use in measuring yeast cell numbers during the aerobic growth of yeast in grape juice. The response of the nephelometer to yeast cells in suspension decreased with increasing sugar concentration, and the decrease was dependent on the yeast population. Yeast cell number could be corrected from the observed nephelometer response with a calibration factor dependent on sugar concentration. Yeast populations as determined from the nephelometer response were compared to those determined by haemocytometer and optical density.
The sporulation gene spoVE of Bacillus subtilis was cloned by the "prophage transformation" method in temperate phage φ105. The specialized transducing phage, φ105spoVE, restored the sporulation of the sporulation-defective mutant of B. subtilis strain 1S51 (spoVE85). Transformation experiments showed that the spoVE gene resides on a 1.7 megadalton EcoRI restriction fragment of the transducing phage genome. Subsequently, the 1.7 megadalton fragment was recloned into the EcoRI site of a plasmid pUB110 and the deletion plasmids having a deletion within the 1.7 megadalton insert were constructed. The plasmid carrying the entire spoVE gene restored the sporulation of strain 5202 (spoVE85recE4) to a frequency of 103spores/ml, but inhibited the sporulation of strain 4309 (spo+ recE4) to a level of 104spores/ml.
Tetrad-forming cocci were isolated from 17 kinds of fermented fish, meat, vegetables, and other materials in Thailand. Out of 58 strains identified, 22 were Pediococcus perltosaceus Mees, 2 were Pedicoccusacidilactici Lindner, 26 were Pediococcus halophilus Mees, 4 were Pediococcus sp., and 4 were "Tetracoccus" sp. They were widely distributed in fermented products in Thailand, and play roles in souring and ripening.