Open Access. Powered by Scholars. Published by Universities.®

Medical Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 4 of 4

Full-Text Articles in Medical Sciences

Identification And Characterization Of Sigma(S), A Novel Component Of The Staphylococcus Aureus Stress And Virulence Responses, Lindsey N. Shaw, Catharina Lindholm, Tomasz K. Prajsnar, Halie K. Miller, Melanie C. Brown, Ewa Golonka, George C. Stewart, Andrej Tarkowski, Jan Potempa Dec 2008

Identification And Characterization Of Sigma(S), A Novel Component Of The Staphylococcus Aureus Stress And Virulence Responses, Lindsey N. Shaw, Catharina Lindholm, Tomasz K. Prajsnar, Halie K. Miller, Melanie C. Brown, Ewa Golonka, George C. Stewart, Andrej Tarkowski, Jan Potempa

Molecular Biosciences Faculty Publications

S. aureus is a highly successful pathogen that is speculated to be the most common cause of human disease. The progression of disease in S. aureus is subject to multi-factorial regulation, in response to the environments encountered during growth. This adaptive nature is thought to be central to pathogenesis, and is the result of multiple regulatory mechanisms employed in gene regulation. In this work we describe the existence of a novel S. aureus regulator, an as yet uncharacterized ECF-sigma factor (sigma(S)), that appears to be an important component of the stress and pathogenic responses of this organism. Using biochemical approaches …


Factors Contributing To The Biofilm-Deficient Phenotype Of Staphylococcus Aureus Sara Mutants, Laura H. Tsang, James E. Cassat, Lindsey N. Shaw, Karen E. Beenken, Mark S. Smeltzer Oct 2008

Factors Contributing To The Biofilm-Deficient Phenotype Of Staphylococcus Aureus Sara Mutants, Laura H. Tsang, James E. Cassat, Lindsey N. Shaw, Karen E. Beenken, Mark S. Smeltzer

Molecular Biosciences Faculty Publications

Mutation of sarA in Staphylococcus aureus results in a reduced capacity to form a biofilm, but the mechanistic basis for this remains unknown. Previous transcriptional profiling experiments identified a number of genes that are differentially expressed both in a biofilm and in a sarA mutant. This included genes involved in acid tolerance and the production of nucleolytic and proteolytic exoenzymes. Based on this we generated mutations in alsSD, nuc and sspA in the S. aureus clinical isolate UAMS-1 and its isogenic sarA mutant and assessed the impact on biofilm formation. Because expression of alsSD was increased in a biofilm but …


The Role Of Extracellular Matrix And Matrix-Degrading Proteases In Neonatal Hypoxic-Ischemic Injury, Christopher C. Leonardo Jun 2008

The Role Of Extracellular Matrix And Matrix-Degrading Proteases In Neonatal Hypoxic-Ischemic Injury, Christopher C. Leonardo

USF Tampa Graduate Theses and Dissertations

Improvements in medical care over recent decades have increased the number of premature and low birth weight infants that survive hypoxic-ischemic (H-I) insults. Because there is a rising incidence in diseases associated with these events, it is critical to develop effective therapies to treat the various resulting neuropathies. Extracellular matrix constitutes the majority of brain parenchyma. Lecticans and matrix-degrading proteases including ADAMTSs (a disintegrin and metalloproteinase with thrombospondin repeats) and matrix metalloproteinases (MMPs) exert effects on cell viability and may be associated with either protective or destructive processes after H-I. Both ADAMTSs (Cross et al. 2006; Tian et al. 2007) …


Food Restriction Compromises Immune Memory In Deer Mice (Peromyscus Maniculatus) By Reducing Spleen-Derived Antibody-Producing B Cell Numbers, Lynn B. Martin, Kristen J. Navara, Michael T. Bailey, Chelsea R. Hutch, Nicole D. Powell, John F. Sheridan, Randy J. Nelson May 2008

Food Restriction Compromises Immune Memory In Deer Mice (Peromyscus Maniculatus) By Reducing Spleen-Derived Antibody-Producing B Cell Numbers, Lynn B. Martin, Kristen J. Navara, Michael T. Bailey, Chelsea R. Hutch, Nicole D. Powell, John F. Sheridan, Randy J. Nelson

Integrative Biology Faculty and Staff Publications

Immune activity is variable in many wild animals, despite presumed strong selection against immune incompetence. Much variation may be due to changes in prevalence and abundance of pathogens (and/or their vectors) in time and space, but the costs of immune defenses themselves may also be important. Induction of immune activity often increases energy and protein expenditure, sometimes to the point of compromising fitness. Whether immune defenses are expensive to maintain once they are generated, however, is less well appreciated. If so, organisms would face persistent challenges of allocating resources between immunity and other expensive physiological processes, which would mandate trade-offs. …