Honors College Thesis
 

The role of sigma factors in production of cyanobacterial natural products: Escherichia coli as a heterologous expression host

Public Deposited

Downloadable Content

Download PDF
https://ir.library.oregonstate.edu/concern/honors_college_theses/rr172038m

Descriptions

Attribute NameValues
Creator
Abstract
  • Cyanobacteria represent an underexploited source of bioactive natural products of interest to the pharmaceutical industry. Lack of development of these compounds as drug leads is due mainly to myriad practical problems with the producing strains including long doubling times, genetic intractability, and low compound yields. Previous attempts at heterologous expression in quick-growing, genetically amenable hosts such as Escherichia coli and Streptomyces spp. have encountered mixed success, especially with more complex natural products from non-ribosomal peptide synthetase (NRPS) and polyketide synthase (PKS) pathways. The most successful heterologous expression host to date is the filamentous freshwater cyanobacterium Anabaena sp. strain PCC 7120. Here, we examine the ability of heterologously expressed sigma factors identified in the genome of Anabaena sp. strain PCC 7120 to assist E. coli in the recognition of and transcription from native cyanobacterial promoters. A reporter gene expression assay examining the expression of chloramphenicol acetyltransferase from the promoter regions from complex cyanobacterial gene clusters was used to show that sigma factor All7608 is capable of recognizing multiple cyanobacterial promoters in E. coli. Attempts to produce lyngbyatoxin A from its native cyanobacterial gene cluster were unsuccessful, possibly hindered by deficiencies in recognition of cyanobacterial ribosomal binding sites by native E. coli translational machinery.
License
Resource Type
Date Available
Date Issued
Degree Level
Degree Name
Degree Field
Degree Grantor
Commencement Year
Advisor
Non-Academic Affiliation
Rights Statement
Funding Statement (additional comments about funding)
  • Funding for this project was provided from the College of Pharmacy, Oregon State University, a New Investigator Grant from the Medical Research Foundation of Oregon (Grant #1415) and an AREA award grant from the National Institutes of Health (1R15GM117541-01A1) to Benjamin Philmus, a Professional Development Award from the Oregon State Postdoctoral Association to Patrick Videau, and an Honors Experience Scholarship from the University Honors College and an Undergraduate Summer Research Scholarship from the College of Pharmacy to Kaitlyn Wells. 
Publisher
Peer Reviewed
Language
Replaces

Relationships

Parents:

This work has no parents.

In Collection:

Items

Thumbnail Title Date Uploaded Visibility Actions
file details WellsKaitlynN2017.pdf 2017-07-29 Public Download