Graduate Thesis Or Dissertation
 

Mineral Surfaces as Agents of Environmental Proteolysis: Mechanisms and Controls

Public Deposited

Downloadable Content

Download PDF
https://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/p5547x52n

Descriptions

Attribute NameValues
Creator
Abstract
  • The bottleneck in the turnover of soil organic matter (SOM) is the conversion of large molecular compounds into smaller compounds that can be transported through a cell membrane of a microbe for processing. Once inside the cell, organic compounds can be converted into biomass or be respired. The microbial depolymerization of SOM by microbes is catalyzed by extracellular enzymes. SOM is intimately associated with the mineral matrix, which can affect turnover by interfering with the accessibility of OM or the function of extracellular enzymes. Interactions with the mineral matrix have been primarily associated as a protective mechanism of SOM against microbial degradation. But it has been observed that soil minerals can participate in the chemical degradation of organic compounds This dissertation attempts to address whether soil minerals have the capacity to chemically modify or break down proteins in order to infer whether the mineral matrix has the capacity to alter extracellular enzymes in soil. The following research aims to identify what conditions are conducive to protein modifications by mineral interactions. The first research chapter explored how mineral surfaces can switch from sorbents to reactants towards proteins under a gradient of increasing energy similar to fireline intensities experienced in wildfires. The second research chapter observed the mechanisms responsible for proteolysis and the locations of cleavage by minerals. The last research chapter revealed that inserting an amino acid trimer to a model protein was sufficient in altering protein-mineral interactions such as adsorption and fragmentation. Together this work provides evidence to expand the role of protein-mineral interactions to include the degradative functionality of minerals in the cycling of SOM.
Contributor
License
Resource Type
Date Issued
Degree Level
Degree Name
Degree Field
Degree Grantor
Commencement Year
Advisor
Committee Member
Academic Affiliation
Subject
Rights Statement
Publisher
Peer Reviewed
Language
Embargo date range
  • 2019-01-01 to 2021-02-01

Relationships

Parents:

This work has no parents.

In Collection:

Items

Thumbnail Title Date Uploaded Visibility Actions
file details ChaconStephanyS2018.pdf 2018-12-31 Public Download