Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 2 of 2
Full-Text Articles in Life Sciences
Defensin Transcript Distribution In Tissues And Life Stages Of The Ixodid Ticks Amblyomma Americanum And Ixodes Scapularis, Stephanie M. Todd
Defensin Transcript Distribution In Tissues And Life Stages Of The Ixodid Ticks Amblyomma Americanum And Ixodes Scapularis, Stephanie M. Todd
Biological Sciences Theses & Dissertations
A number of bacterial, viral, and protozoan diseases are transmitted to humans via arthropods. Arthropods possess an innate immune system to destroy invading microorganisms. However, arthropods unable to rid their systems of pathogens function as disease vectors. The American dog tick, Dermacentor variabilis, destroys invading Borrelia burgdorferi spirochetes, preventing transmission. In contrast, the black-legged tick, Ixodes scapularis, which is unable to destroy acquired B. burgdorferi, successfully vectors the pathogen. The Lone Star tick, Amblyomma americanum, vectors a similar pathogen called Borrelia lonestari. The distribution of defensin, an antimicrobial peptide of the innate immune system, was examined in A. americanum and/. …
Effect Of Magnesium On The Production Of Scna And Scnr By Streptococcus Pyogenes, Strain Ff22, Laura E. Quinn
Effect Of Magnesium On The Production Of Scna And Scnr By Streptococcus Pyogenes, Strain Ff22, Laura E. Quinn
Biological Sciences Theses & Dissertations
The lantibiotic SA-FF22, produced by Streptococcus pyogenes strain FF22, was the first described antimicrobial peptide produced by a Streptococcus species. S. pyogenes is a group A Streptococcus responsible for such human illness as strep-throat, rheumatic fever, necrotizing fasciitis, endocarditis, and meningitis. Previous studies of SA-FF22 have shown that antimicrobial activity is lost in the presence of lmM magnesium. We hypothesize that the lack of SA-FF22 activity in the presence of magnesium is due to an absence of transcription of scnA, the gene encoding SA-FF22. The lack of transcriptional activation of scnA may be due to an absence of ScnR, a …