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

Biochemistry, Biophysics, and Structural Biology Commons

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

Articles 1 - 5 of 5

Full-Text Articles in Biochemistry, Biophysics, and Structural Biology

Discovering Virally Encoded Proteins That Block Type Iv Crispr Immune Systems, Andrew Williams Dec 2021

Discovering Virally Encoded Proteins That Block Type Iv Crispr Immune Systems, Andrew Williams

Fall Student Research Symposium 2021

Bacteria and the viruses that infect them have been at war from the beginnings of life until today. Due to selective pressure from viral infection, bacteria have evolved various biological defense systems, including CRISPR-Cas systems that use a genetic memory of previous viral encounters to protect against future invasions. However, recently it has been shown that viruses have evolved counter-strategies to evade CRISPR systems. Virally encoded proteins called anti-CRISPRs use a variety of mechanisms to block the activity of CRISPR immune systems in order to infect bacterial cells. The Jackson lab at USU recently showed that a Type IV-A CRISPR-Cas …


The Flavoprotein Rcla Is A Hypothiocyanous Acid Reductase, Irina Chapman Dec 2021

The Flavoprotein Rcla Is A Hypothiocyanous Acid Reductase, Irina Chapman

Masters Theses

Reactive chlorine species (RCS) - hypochlorous acid (HOCl), hypothiocyanous acid (HOSCN), and chloramines - are powerful antimicrobial oxidants generated by the innate immune system. Bacteria developed defense mechanisms against RCS, which are highly toxic for invading pathogens. One such defense system involves RclA, an enzyme from the flavin disulfide reductase family, which is massively upregulated upon exposure of Escherichia coli to RCS. Recent research suggests that RclA functions as a Cu(II) reductase to provide resistance against RCS. However, the exact mechanism used by RclA was subject to debate. In this study, we demonstrate that RclA is unlikely to function as …


Determination Of The Structure, Function, And Mechanism Of Type Iv Crispr-Cas Prokaryotic Defense Systems, Hannah Nicole Taylor Aug 2021

Determination Of The Structure, Function, And Mechanism Of Type Iv Crispr-Cas Prokaryotic Defense Systems, Hannah Nicole Taylor

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Bacteria are under constant threat of invasion by bacteriophage (viruses which infect bacteria). To prevent bacteriophage from entering and overtaking the bacteria, bacteria utilize defense systems to identify and destroy foreign elements. One method of defense is called CRISPR-Cas (Clustered Regularly Interspaced Short Palindromic Repeats – CRISPR-Associated). Many different bacteria and most archaea use CRISPR-Cas systems. There are many diverse types of CRISPR-Cas systems, each of which provides defense in a slightly different way. One such CRISPR-Cas type is called type IV. The type IV CRISPR-Cas system is poorly understood and there are very few studies published on type IV …


Probing Interactions Between Canonical Nox Domains, Akua Acheampong May 2021

Probing Interactions Between Canonical Nox Domains, Akua Acheampong

Master of Science in Integrative Biology Theses

NAPDH oxidase enzymes (NOXes) reduce molecular oxygen to superoxide and other ROS. NOXes contain a catalytic core comprising a heme-containing transmembrane (TM) domain and a cytoplasmic dehydrogenase (DH) domain that binds the substrate NADPH and the cofactor. Previously, NOXes were only characterized in eukaryotes, but have recently been identified in prokaryotes, namely bacteria. Due to their constitutive activity and solubility in detergent, bacterial NOXes, such as Streptococcus Pneumoniae NOX, have emerged as a model for studying NOXes. Past research studies in NOXes have identified conserved, putative interacting regions at the interface of the TM and DH domains: the TM B-loop, …


Pathogenicity Of Staphylococcus Agnetis Associated With Lame Broilers With Osteomyelitis, Sura Faris Salih Zaki May 2021

Pathogenicity Of Staphylococcus Agnetis Associated With Lame Broilers With Osteomyelitis, Sura Faris Salih Zaki

Graduate Theses and Dissertations

We developed High Resolution Melt Analysis (HERMA) as a rapid and reliable molecular diagnostic assay for the detection and identification of the main bacterial species recovered from the blood and lesions of bacterial chondronecrosis with osteomyelitis (BCO) from the lame broilers at the University of Arkansas poultry research farm. Also, the present study confirms that raising young birds on suspended wire flooring has been proved to successfully induce lameness attributable to BCO with birds being more susceptible to bacteraemia than those that were raised on litter flooring. The newly described pathogen, Staphylococcus agnetis, has been reported to be overrepresented in …