• Login
    View Item 
    •   DSpace@RPI Home
    • Rensselaer Libraries
    • RPI Theses Online (Complete)
    • View Item
    •   DSpace@RPI Home
    • Rensselaer Libraries
    • RPI Theses Online (Complete)
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Engineering recombinant microbial communities for cellulose degradation and utilization

    Author
    Kalbarczyk, Karolina Zbigniew
    View/Open
    180679_Kalbarczyk_rpi_0185E_11337.pdf (9.436Mb)
    Other Contributors
    Collins, Cynthia H.; Koffas, Mattheos A. G.; Tessier, Peter M.; Barquera, Blanca L.;
    Date Issued
    2018-08
    Subject
    Chemical engineering
    Degree
    PhD;
    Terms of Use
    This electronic version is a licensed copy owned by Rensselaer Polytechnic Institute, Troy, NY. Copyright of original work retained by author.;
    Metadata
    Show full item record
    URI
    https://hdl.handle.net/20.500.13015/2727
    Abstract
    Recent environmental concerns have intensified the need to develop systems to degrade waste biomass for use as an inexpensive carbon source for microbial chemical production. Current approaches to biomass utilization rely on pretreatment processes that include expensive enzymatic purification steps for the requisite cellulases. To address this challenge, synthetic communities can be engineered to streamline cellulose degradation and utilization, and eliminate the need for costly enzyme purification. Therefore, we aimed to engineer a synthetic microbial system with specialized modules designed for each compartmentalized task, with the first module dedicated to cellulose degradation and the second module specialized for bioproduct synthesis. To construct the cellulose degradation module, EGI1, an endoglucanase, and Cel9AT, a multimodular cellulase, were targeted for secretion from B. megaterium. A small library of signal peptides (SPs) with five amino acid linkers was selected to tag each cellulase for secretion.; Cellulase activity against amorphous cellulose was confirmed, and the most active SP constructs were identified as EGI1 with the LipA SP and Cel9AT with the YngK SP. Both strains were optimized for cellulase expression, and activity of the enzymes was characterized individually and in tandem to demonstrate synergistic cellulolytic activity in coculture. The secreted cellulases were reacted with amorphous cellulose under a range of different conditions, and the resulting glucose supported the growth of the second target module, an E. coli strain to be used for production of violacein, an antimicrobial pharmaceutical product with anti-tumor properties. A series of studies investigated the compatibility of the two modules and the cellulose degradation reaction. The construction of a two-module system for efficient cellulose degradation and utilization demonstrated the value of the modular system design, to allow bacterial strains to be interchanged or linked with other engineered bacterial strains for the efficient production of high value molecules.;
    Description
    August 2018; School of Engineering
    Department
    Dept. of Chemical and Biological Engineering;
    Publisher
    Rensselaer Polytechnic Institute, Troy, NY
    Relationships
    Rensselaer Theses and Dissertations Online Collection;
    Access
    Restricted to current Rensselaer faculty, staff and students. Access inquiries may be directed to the Rensselaer Libraries.;
    Collections
    • RPI Theses Online (Complete)

    Browse

    All of DSpace@RPICommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsThis CollectionBy Issue DateAuthorsTitlesSubjects

    My Account

    Login

    DSpace software copyright © 2002-2022  DuraSpace
    Contact Us | Send Feedback
    DSpace Express is a service operated by 
    Atmire NV