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Full-Text Articles in Biochemistry
Isolation And Characterization Of A Novel Motility Mutant In Salmonella Typhimurium, David Matthew Chacko
Isolation And Characterization Of A Novel Motility Mutant In Salmonella Typhimurium, David Matthew Chacko
Loma Linda University Electronic Theses, Dissertations & Projects
A new mutant, BT40, isolated from mutagenized cultures of S. typhimurium was deficient in chemotaxis (Che- phenotype) in tryptone semisoft agar, but had random motility with a tumbling frequency (37%) similar to that of the parental strain, ST23 (39%). In spatial assays accumulation of BT40 cells in capillary tubes containing attractants was decreased by 33%-59% compared to ST23, but BT40 had a normal response to attractants in temporal assays. The methylation level of the chemotactic proteins was decreased in BT40. At room temperature, the mean swimming speed was 11 μm/s for BT40 and 20 μm/s for ST23; more BT40 …
Response Of A Nitrifying Biofilm To Copper, Denise Moldroski Mott
Response Of A Nitrifying Biofilm To Copper, Denise Moldroski Mott
Masters Theses
In pure cultures of Nitrosomonas, copper is known to cause a stimulation of nitrification at low levels (≤ 0.03 mg Cu+2/1) and an inhibition affect at higher levels (≥ 0.05 mg Cu+2/1). Nitrifying activated sludges are much more tolerant of copper showing only 75% inhibition at 150mg Cu+2/1. The purpose of this paper was to determine the copper sensitivity of a nitrifying biofilm grown in a continuous flow trickling filter system.
A continuous flow trickling filter system was built using limestone chips for the biofilm substrate. The biofilm was established from secondary effluent. …