Graduate Thesis Or Dissertation

 

Evaluation of bioluminescence as a measure of bacterial cell density in porous media Public Deposited

Downloadable Content

Download PDF
https://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/ff365755c

Descriptions

Attribute NameValues
Creator
Abstract
  • Salicylate-induced, lux gene dependent bioluminescence was measured using a cooled charge-coupled device (CCD) camera to evaluate its potential as a quantitative measurement of cell density of Pseudomonas fluorescens HK44 in porous media. The CCD camera was able to detect bioluminescence from cell densities between 1x10⁶ and 1x10⁸ cells/ml in both liquid suspensions and saturated sand, and between 5x10⁶ and 8.5x10⁸ cells/ml in unsaturated sand at 7.0% (cm³/cm³) volumetric water content. After lux gene induction by 100 mg/L salicylate, light emission increased with the square of time and linearly with increasing cell density. A model was developed to relate light emission with cell density. Similar values were determined for the rate of increase in light emission, B', [12 (± 0.2) x 10⁻¹⁰ light units/(cell-min²)] for suspensions of cells in aqueous media and in saturated or unsaturated sand. Growth phase of HK44 significantly influenced the first detectable time (FDT) of bioluminescence response with log and stationary phase cells expressing FDT values of 2.5 and 1.8 hours, respectively, after induction. The effect of growth phase was eliminated by the addition of 10 to 250 mg/L glucose and salicylate simultaneously. Oxygen availability limited the upper cell density limit (1x10⁸ cells/ml) that could be measured by bioluminescence with the CCD camera. While each camera system and bioluminescent organism combination will require calibration, a CCD camera system has the potential to quantify bacterial bioluminescence as a means to study microbial growth and dynamics non-destructively in two-dimensional porous media.
Resource Type
Date Available
Date Issued
Degree Level
Degree Name
Degree Field
Degree Grantor
Commencement Year
Advisor
Committee Member
Academic Affiliation
Non-Academic Affiliation
Subject
Rights Statement
Publisher
Peer Reviewed
Language
Digitization Specifications
  • File scanned at 300 ppi (Monochrome, 256 Grayscale) using Capture Perfect 3.0 on a Canon DR-9050C in PDF format. CVista PdfCompressor 4.0 was used for pdf compression and textual OCR.
Replaces

Relationships

Parents:

This work has no parents.

In Collection:

Items