Significance of low-temperature growth associated with the fecal coliform response, indole production, and pectin liquefaction in Klebsiella

In the genus Klebsiella, the growth respnse in nutient broth at 10 degrees C correlates inversely with the operational definition of a fecal coliform and not merely with the ability to grow at 44.5 degrees C. Of the fecal coliform-positive Klebsiella, 97% did not grow at 10 degrees C after 72 h of incubation. Conversely, 97% of the fecal coliform-negative isolates grew at 10 degrees C. The amount of growth at 10 degrees C varied among the fecal coliform-negative isolates and was found to correlate with indole production and pectin liquefaction. Low-temperature growth associated with specific biochemical tests can be used to differentiate several groups in the genus Klebsiella. Three main groups were discerned. Group I consists of indole-negative, pectin-nonliquefying, fecal coliform-positive isolates that do not grow at 10 degrees C. Group II isolates are differentiated from group I by a fecal-coliform-negative response and growth at 10 degrees C. Group III are indole-positive, pectin-liquefying, fecal coliform-negative isolates that grow at 10 degrees C. In our culture collection, isolates of group I are most frequently of human/animal clinical origins, whereas isolates of groups II and III are predominantly derived from the environment.     

Photoelectric signals from dried oriented purple membranes of Halobacterium halobium

In dried oriented samples of purple membrane isolated from Halobacterium halobium, the photoelectric activity decreases and the light adaptation vanishes when the water content of the sample is lowered. In the photocycle the first steps of the proton movement were accelerated with decreasing humidity, while the last steps of the photocycle could not be observed. From the analysis of the photoelectric signal we conclude that at low humidities the protons move forward in the L decay and return to their original place during M decay.     

Effect of algal inoculation on the yield and vitamin C content of two varieties of tomato

Summary Two varieties of tomato (Pusa Rubi and Selection 120) positively responded to algal inoculation in terms of the yield of fruits and shoots, but there was no significant effect on the vitamin C content of the fruits. A combined application of urea and algae was more effective than the application of urea alone.