Dr. Jon Henrikson

EDUCATION

Dr. Jon Henrikson (Mentor)

Project 1:  Method Development and Determination of Glycine Metal Complex pKa’s by NMR and Visible Spectroscopy 

The use of electron withdrawing groups is a well-known approach to change the chemical properties of a molecule, including the acidity. Our project’s goal is to quantify the changes in pK_a of previously synthesized glycine containing ligands with the presence or absence of electron withdrawing groups attached to the molecule in organic solvents. Challenges in determining the pKa’s of these ligands include monitoring the equilibrium of a weak acid-weak base chemical reaction and the use of different methods in determining the acidity of a proton in organic solvent conditions, since common aqueous methods are not possible.  This project applies proton nuclear magnetic resonance (¹H-NMR) and visible spectroscopy as means to monitoring the weak acid-weak base interaction and to quantify the pK_a by proton integration and wavelength absorbance changes, respectively.  

Project 2:  Elucidating Changes in Antimicrobial Production of Streptomyces sps. Through Small-Molecule Signaling

BACKGROUND 

Secondary metabolites (natural products) have had a long, rich history with respect to their importance in the treatment of disease.  Since 1980, greater than 60% of drugs developed were derived from natural sources. However, the difficulty in discovery and isolation of natural products has caused a shift in development of pharmaceutical drug leads (i.e. combinatorial chemistry). Over the last decade, analysis of microbial genomes has demonstrated that only a fraction of the possible microbial secondary metabolites have been explored.  This discovery has sparked significant interest in probing microbial genomes for new and bioactive natural products.   One area of interest for the induction of natural products through co-culture microbial communication through small molecules.   

PURPOSE 

Currently, we have explored some microbial interactions within co-culture conditions, but need to develop a way to discover the small molecules utilized in the microbial communication process.  This involves exploring different methods of isolation.  The literature has shown that there are instances in which small molecules involved in communication can be volatile.  By using solid-phase micro extraction (SPME) techniques, we may be able to develop a method to monitor for changes in the volatile molecule profile of microbes under co-culture conditions.   

The long-term goals of this project is to explore the relationship between volatile microbial molecules which are heightened under co-culture conditions, with respect to changes in overall natural product production.  Bioassays and chromatography techniques will be used to look for secondary metabolite changes.  Once a secondary metabolite of interest is targeted, purification and structure determination of the compound will be done through various analytical methods. 

Project 3 (In development):  Monitoring Changes in Coffee Bean Volatiles over Time through Solid-Phase Micro Extraction (SPME). 

CONTACT INFORMATION

Email: jon.henrikson@swosu.edu Office Number: CPP 205-A
Phone Number: 580-774-3120

TEACHING: BASIC COURSES

CHEM 1004 Gen Chem
CHEM 1004L Gen Chem Lab
CHEM 1203 Gen Chem I
CHEM 1252 Gen Chem I Lab
CHEM 1303 Gen Chem II
CHEM 1352 Gen Chem II Lab

TEACHING: ANALYTICAL CHEMISTRY

CHEM 3124/L Quantitative Analysis/Lab
CHEM 4234/L Instrumental Analysis/Lab

OTHER ACTIVITIES

AUG 2014-PRESENT
Chemistry Club Sponsor

RECENT PUBLICATIONS

Henrikson, Jon C.; Ellis, Trevor K.; King, Jarrod; Chichewicz, Robert H.; Reappraising the Structures and Distribution of Metabolites from Black Aspergilli Containing Uncommon 2-Benzyl-4H-pyran-4-one and 2-Benzylpyridin-4(1H)-one Systems. Journal of Natural Products, 2011, 74, 1959-1964.

Cichewicz, Robert H.; Henrikson, Jon C.; Wang, Xiaoru; Branscum, Katie. Strategies for Accessing Microbial Secondary Metabolites from Silent Biosynthetic Pathways. In Manual of Industrial Microbiology and Biotechnology, 3rd Edition; Baltz, R. H.; Davies, J. E.; Demain, A. L. Eds., ASM Press, 2010, 78-95.  

Henrikson, Jon C.; Gharfeh, Majed S.; Easton, Anne C.; Easton, James D.; Glenn, Karen L.; Shadfan, M.; Mooberry, Susan L.; Hambright, K. David; Cichewicz, Robert H. Reassessing the Ichthyotoxin Profile of Culture Prymnesium parvum (Golden Algae) and Comparing it to Samples Collected from Recent Freshwater Bloom and Fish Kill Events in North America. Toxicon, 2010, 55, 1396-1404.  

Fisch, Katja M.; Gillaspy Allison F.; Gipson, M.; Henrikson, Jon C.; Hoover, Ashley R.; Jackson, L.; Najar, F.Z.; Waegele, H.; Cichewicz, Robert H. Chemical Induction of Silent Biosynthetic Pathway Transcription in Aspergillus niger. Journal of Industrial Microbiology and Biotechnology. 2009, 26, 1199-1213.  

Henrikson, Jon C.; Hoover, Ashley R.; Joyner, P. Matthew; Cichewicz, Robert H. A Chemical Epigenetics Approach for Engineering in situ Biosynthesis of a Cryptic Natural Product from Aspergillus niger. Organic and Bimolecular Chemistry. 2009, 7, 435-438.  

Williams, Russell B.; Henrikson, Jon C.; Hoover, Ashley R.; Lee, Andrlynn E.; Cichewicz, Robert H. Epigenetic Remodeling of the Fungal Secondary Metabolome. Organic and Biomolecular Chemistry. 2008, 6, 1895-1897