James R. Johnson

BS (Auburn); PhD (Duke)
Associate Professor of Biology
215-596-8521
e-mail: j.johnso@usip.edu

Research Interests
Molecular mechanisms regulating gene expression and gene product function; analysis of protein factors and DNA structures which regulate gene activity in Escherichia coli K 12 and Staphylococcus aureus; microbial sulfur metabolism.

Representative Publications/Presentations
(undergraduates underlined)
Bala, G.A., C.D. Collier, M.R. Emmett and J.R. Johnson. (1989). Characterization of two mutant metJ proteins with reduced, temperature dependent capacity to control E. coli K 12 met regulon elements. J. Bacteriol. 171; 4095-4099.

Collier, C.D. and J.R. Johnson. (1990). the metJ193 allele contains a point mutation which alters the hydrophobic pocket responsible for in vitro binding of S-adenosylmethionine: Effects upon cell growth and induction of met regulon expression. J. Bacteriol. 172:3918-3924.

Abraham, C. and J. Johnson, 2002. Investigation of cysteic acid, 2-mercaptoethanolamine, and cysteine-sulfinic acid as nutritional substitutes for cysteine or as competitive inhibitors of cysteine metabolism by Staphylococcus aureus. Presented at the USP Sigma Xi Thirteenth Annual Undergraduate Research Symposium, April 2002.

Hartzell, S. and J. Johnson, 2002. Comparison of growth of Staphylococcus aureus using varying concentrations of cysteine, cysteine and glutathione and measuring the degradation of the latter compounds using analytical methods. Presented at the USP Sigma Xi, Thirteenth Annual Undergraduate Research Symposium, April 2002.

Abdullah, I. and J.R. Johnson, 2003. A thin-layer chromatographic method that can be used to detect and measure glutathioine degradation. Presented at the USP Fourteenth Annual Sigma Xi Undergraduate Research Symposium, April 2003.

Costleigh, J.R. and J. R. Johnson, 2003. Development of a biochemical assay to determine if Staphylococcus aureus is able to reduce the disulfide linkage in cystine. Presented at USP Fourteenth Annual Sigma Xi Undergraduate Research Symposium, April 2003.