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Cell and Developmental Biology

University of Tennessee, Knoxville

Doctoral Dissertations

Chemotaxis

Publication Year

Articles 1 - 2 of 2

Full-Text Articles in Life Sciences

Characterization Of The Function Of The Azospirillum Brasilense Che1 Chemotaxis Pathway In The Regulation Of Chemotaxis, Cell Length And Clumping, Amber Nicole Bible May 2012

Characterization Of The Function Of The Azospirillum Brasilense Che1 Chemotaxis Pathway In The Regulation Of Chemotaxis, Cell Length And Clumping, Amber Nicole Bible

Doctoral Dissertations

Azospirillum brasilense is a gram-negative alphaproteobacterium that lives in the soil where it colonizes the root surfaces of cereals and grasses. The genome of A. brasilense has recently been sequenced and shown to possess four different chemotaxis-like operons. This dissertation project focused on characterizing the Che1 chemotaxis-like signal transduction pathway, which was initially implicated in regulation of the chemotaxis behavior. Deletions of individual genes within the Che1 pathway did not exhibit a null chemotaxis phenotype, leading us to investigate the role of this pathway in the lifestyle of A. brasilense and the mechanism(s) by which it functions. We have used …


Identifying Mechanisms Associated With Innate Immunity In Cows Genetically Susceptible To Mastitis, Alexandra Alida Elliott Dec 2010

Identifying Mechanisms Associated With Innate Immunity In Cows Genetically Susceptible To Mastitis, Alexandra Alida Elliott

Doctoral Dissertations

Mastitis, or mammary gland inflammation, causes the greatest loss in profit for dairy producers. Mastitis susceptibility differs among cows due to environmental, physiological, and genetic factors. Prior research identified a genetic marker in a chemokine receptor, CXCR1, associated with mastitis susceptibility and decreased neutrophil migration. Current research seeks to identify reasons behind mastitis susceptibility by validating this model through in vivo challenge with Streptococcus uberis and studying specific mechanisms causing impaired neutrophil migration. Holstein cows with GG (n=19), GC (n=28), and CC (n=20) genotypes at CXCR1+777 were challenged intramammarily with S. uberis strain UT888. After challenge 68% of quarters from …