Structural Studies of the Bacterial Histidine Kinases RetS and GacS, Key Components of the Multikinase Network that Controls the Switch Between a Motile Invasive Lifestyle and a Sessile Biofilm Lifestyle in Pseudomonas aeruginosa

Simple item page
dc.contributor.authorRyan, Kylie Meghanen
dc.contributor.committeechairSchubot, Florian Daviden
dc.contributor.committeememberYang, Zhaominen
dc.contributor.committeememberScharf, Birgiten
dc.contributor.committeememberCaswell, Clayton Christopheren
dc.contributor.departmentBiological Sciencesen
dc.date.accessioned2022-06-22T16:29:34Zen
dc.date.available2022-06-22T16:29:34Zen
dc.date.issued2021-11-15en
dc.description.abstractSignal transduction networks enable organisms to respond to environmental stimuli. Bacteria utilize two-component systems (TCSs) and phosphorelays as their primary means of signal transduction. Histidine kinase (HK) and response regulator (RR) proteins comprise these TCSs and phosphorelays. Previously, signal transduction within TCSs and phosphorelays was thought to only occur through a linear series of phosphotransfers between HKs and RRs. Recently multikinase networks have been shown to be involved in TCS and phosphorelay signal transmission. A multikinase network that includes the HKs RetS and GacS controls the switch between the motile invasive lifestyle and the sessile biofilm lifestyle of the opportunistic human pathogen Pseudomonas aeruginosa. GacS promotes the sessile biofilm lifestyle, while RetS promotes the motile invasive lifestyle via the inhibition of GacS. This inhibition occurs through three distinct mechanisms. Two of the mechanisms are dephosphorylating mechanisms and the third mechanism is a direct interaction between RetS and GacS which results in the inhibition of GacS autophosphorylation. This study examines the direct binding interaction between RetS and GacS using structural biology. We observed a heterodimeric RetS-GacS complex in which the canonical homodimerization interface was replaced with a heterodimeric interface. Heterodimerization between bacterial HKs is currently a novel observation, but it is likely that other HKs heterodimerize. The RetS-GacS direct interaction can serve as a model for HK-HK binding in multikinase networks.en
dc.description.abstractgeneralThe way in which bacteria assess and respond to their environment is of great interest to microbiologists. Bacteria transmit environmental signals via protein interactions. Some of these interactions involve the transfer of phosphate groups, and some involve a direct binding interaction between proteins. We are investigating a direct binding interaction between two proteins, RetS and GacS. These proteins control whether Pseudomonas aeruginosa, an opportunistic pathogen of humans, causes an acute infection, which is characterized by motility and invasiveness, or a chronic infection, which is characterized by a sessile biofilm lifestyle, in a human host. Through the use of structural biology techniques we have visualized the three-dimensional structure of the complex between RetS and GacS. This complex has provided insight into the role of the RetS-GacS interaction in controlling the infection state of P. aeruginosa.en
dc.description.degreeDoctor of Philosophyen
dc.format.mediumETDen
dc.identifier.othervt_gsexam:33149en
dc.identifier.urihttp://hdl.handle.net/10919/110871en
dc.language.isoenen
dc.publisherVirginia Techen
dc.rightsIn Copyrighten
dc.rights.urihttp://rightsstatements.org/vocab/InC/1.0/en
dc.subjectbacterial histidine kinaseen
dc.subjectprotein-protein interactionsen
dc.subjectbiofilmen
dc.subjectPseudomonas aeruginosaen
dc.subjectTwo-component systemsen
dc.subjectcrosstalken
dc.titleStructural Studies of the Bacterial Histidine Kinases RetS and GacS, Key Components of the Multikinase Network that Controls the Switch Between a Motile Invasive Lifestyle and a Sessile Biofilm Lifestyle in Pseudomonas aeruginosaen
dc.typeDissertationen
thesis.degree.disciplineBiological Sciencesen
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen
thesis.degree.leveldoctoralen
thesis.degree.nameDoctor of Philosophyen

Files

Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
Ryan_KM_D_2021.pdf
Size:
2.66 MB
Format:
Adobe Portable Document Format
Download

Collections

Doctoral Dissertations