Senior Honors Projects, 2010-2019

Creative Commons License

Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.

Date of Graduation

Spring 2016

Document Type


Degree Name

Bachelor of Arts (BA)


Department of Biology


Jonathan D. Monroe


Experimental evidence indicates that the family of beta-amylase (BAM) proteins is largely responsible for the hydrolysis of starch in land plants. In Arabidopsis thaliana there are nine BAM genes, six of which are targeted to the chloroplast, but only four of those are presumed to be catalytically active: BAM1, -2, -3, and -6. Currently, little is known about the expression, characterization, or function of BAM6. Our study of starch accumulation in Arabidopsis indicates that BAM6 may be playing a role in older plants, although it has a minimal role in young plants. To further investigate the function of BAM6 we over-expressed the BAM6 protein by ligating the mature protein coding sequence in fusion with a His-tag into pETDuet-1, an E. coli expression vector and purified the protein by affinity chromatography. Using the purified BAM6 protein, beta-amylase activity assays were conducted to begin to characterize BAM6. The effects of pH and temperature on BAM6 activity revealed maximum activity at pH 7.5 and 39 °C, which more closely resembles the profile of BAM1, an enzyme that is known to function primarily during the day. These findings indicate that BAM6 may also contribute to starch metabolism mostly during the day.



To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.