Microbiology Commons^™

Characterization Of A Staphylococcal Trimethoprim Resistance Gene, Jerald Preston Coughter

Theses and Dissertations

Trimethoprim resistance(Tp r) is encoded by conjugative plasmids in clinically significant staphylococcal isolates. Two genetically and physically similar plasmids from S. aureus, pG01 and pGOS, have Tp r genes that map in different locations on these plasmids. In order to study the relatedness of the Tp r genes and their products to other known Tp r genes, a 1.2 kb fragment of pG01 and a 4.2 kb fragment of pGOS were cloned in E. coli and used as probes for in situ filter hybridization experiments.

A 500 base pair subclone of the original 1.2 kb fragment containing only the staphylococcal …

Degradation Of Human Anaphylatoxin C3a By Rat Peritoneal Mast Cells: A Role For The Secretory Granule Enzyme Chymase And Heparin Proteoglycan, James Edmund Gervasoni Jr

Theses and Dissertations

Purified human C3a was iodinated (¹²⁵I-C3a) and used to study the interaction of labeled peptide with rat peritoneal mast cells (RMC). Cellular binding of ¹²⁵I-C3a occurred within 30 sec, followed by a rapid dissociation from the cell. Both the binding of ¹²⁵I-C3a and the rate of dissociation from the cell were temperature dependent. At 0°C, the binding of ¹²⁵I-C3a was increased and the rate of dissociation reduced, as compared to 37°C. Once ¹²⁵I-C3a was exposed to RMC, it lost the ability to rebind to a second batch of RMC. Analysis of the supernatants by …