Functional analysis of a bacterial phosphohistidine phosphatase / Jane Elizabeth Schulte.

Format:

Book

Thesis/Dissertation

Author/Creator:

Schulte, Jane Elizabeth, author.

Contributor:

University of Pennsylvania. Department of Biochemistry and Molecular Biophysics, degree granting institution.

Goulian, Mark, degree supervisor.

Language:

English

Subjects (All):

Microbiology.

Biochemistry.

Molecular biology.

Biochemistry and Molecular Biophysics--Penn dissertations.

Penn dissertations--Biochemistry and Molecular Biophysics.

Local Subjects:

Microbiology.

Biochemistry.

Molecular biology.

Biochemistry and Molecular Biophysics--Penn dissertations.

Penn dissertations--Biochemistry and Molecular Biophysics.

Genre:

Academic theses.

Physical Description:

1 online resource (100 pages)

Contained In:

Dissertations Abstracts International 81-09B.

Place of Publication:

[Philadelphia, Pennsylvania] : University of Pennsylvania ; Ann Arbor : ProQuest Dissertations & Theses, 2019.

Language Note:

English

System Details:

Mode of access: World Wide Web.

text file

Summary:

One common means to regulate protein activity is through phosphorylation. Protein phosphatases exist to reverse this process, returning the protein to the unphosphorylated form. The vast majority of characterized protein phosphatases target phosphoserine, phosphothreonine, and phosphotyrosine. A widely conserved phosphohistidine phosphatase was identified in Escherichia coli twenty years ago but remains relatively understudied. This bacterial protein is called signal inhibitory factor X (SixA) and belongs to a large family of phosphatases and phosphotransferases. Prior to this work, a single protein target of SixA was known: the E. coli histidine kinase ArcB. Here we analyze an ArcB-independent growth defect of a sixA deletion in E. coli. A screen for suppressors, analysis of various mutants, and phosphorylation assays indicate that SixA modulates phosphorylation of the nitrogen-related phosphotransferase system. This system is a widely conserved bacterial pathway that is regulated by nitrogen and carbon metabolism. It affects diverse aspects of bacterial physiology through the phosphorylation states of its protein components, EINtr, NPr, and EIIANtr, which receive phosphoryl groups on histidine residues. Despite over two decades of research, a mechanism for dephosphorylating this system has not been reported. Our results suggest a model in which SixA removes phosphoryl groups from the nitrogen-related phosphotransferase system by acting on NPr. This work uncovers a new role for the phosphohistidine phosphatase SixA and, through factors that affect SixA expression or activity, may point to additional inputs that regulate the nitrogen-related phosphotransferase system.

Notes:

Source: Dissertations Abstracts International, Volume: 81-09, Section: B.

Advisors: Goulian, Mark; Committee members: Rahul Kohli; Jun Zhu; Fevzi Daldal; Igor Brodsky.

Department: Biochemistry and Molecular Biophysics.

Ph.D. University of Pennsylvania 2019.

Local Notes:

School code: 0175

ISBN:

9781392431061

Access Restriction:

Restricted for use by site license.

This item is not available from ProQuest Dissertations & Theses.

This item must not be sold to any third party vendors.