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E J Kirsch

Publications and source records attributed to E J Kirsch.

7 recordsLinked to original sources
PubMed1969

Influence of pH and metal cations on aggregative growth of non-slime-forming strains of Zoogloea ramigera.

Aggregative growth of non-slime-forming strains of Zoogloea ramigera was induced by growing the organisms at a depressed pH. Calcium and magnesium ion was found to reverse aggregative growth of the organisms. Conversely, aggregation was stimulated when the available inorganic cation concentration of the growth medium was lowered by the use of a chelating agent. The aggregative effects of pH depression or cation depletion and the dispersal effects of cation supplementation were observed only during cellular growth. The data suggest that aggregate formation of non-slime-forming strains of Z. ramigera may be related to the calcium or magnesium metabolism of the organisms, or both.

Bacteria↗
PubMed1966

Anaerobic stimulated mixed culture system.

A compartmented, autoclavable culture vessel has been developed for the purpose of studying interactive associations of microorganisms which are essential to the anaerobic decomposition of sewage sludge. The unit employs sterile filter membranes to subdivide the interior culture space into individual compartments. Bacteria cultured in one compartment are denied access to adjacent compartments, even though rapid interchange of nutrients and metabolic waste products occurs throughout the unit. The obligate methane-forming anaerobe, Methanobacillus omelianskii has been successfully grown and concentrated in this system by use of a synthetic medium reduced with sodium sulfide. The feasibility of using this system to study microbial interactions was, in part, demonstrated by growing M. omelianskii in a thoroughly aerated medium which had been biologically reduced by Escherichia coli prior to inoculation with the anaerobe. Under this condition of simulated mixed culture growth, the cell yield of both microorganisms, as well as specific metabolic activities ascribed to each organism, was readily monitored.

Bacteriological Techniques↗