Dr. Keturah Adams is an Assistant Professor of Biochemistry in the Chemistry & Physics Department at Southwestern Oklahoma State University (SWOSU).
EDUCATION
2009 – B.S. Chemistry, Southwestern Oklahoma State University
2012 – M.S. Biological Chemistry, Texas A&M University
2016 – Ph.D. Biological Chemistry, Texas A&M University
2019 – Began teaching at SWOSU
RESEARCH
Sequence Specificity in Recognition of Recombinant Proteins by a Synthetic Molecule
Dr. Keturah A. Adams (Mentor)
Actively accepting research students for credit.
Background. Proteins are perhaps the most versatile molecules that enable several biological processes such as cell signaling, metabolism etc. Mimicking the non-covalent interactions of the proteins has generated numerous small molecules and selected biomolecules which are useful in biological applications such as separation, imaging, diagnostics, drug delivery to name a few. Small molecules can be used as affinity tags to separate targeted proteins in a reversible manner. Other methods include site specifically modifying proteins by fusing small peptide tags such as FLAG (8 amino acids) or large protein domains such as glutathione S-transferase (220 amino acids) to the protein. Even though these modifications are reversible and cleavable, a large protein tag fused to the targeted protein could potentially affect the protein’s structure and functional activity. Attaching fewer residues to the desired protein, its antibody binding partners even though has high specificity, can be expensive and at times unreliable. Based on these problems mentioned above, in my lab I aim to develop a method by which a protein of choice will be directly modified with minimal affinity tag (2-3 neighboring amino acid residues) and targeted by synthetic molecules with high affinity and high specificity. These synthetic molecules known as cucurbit[n]urils. They are a family of organic macrocyclic host molecules made up of glycouril units which possess a non-polar interior bearing two constricted polar entrances where they bind to a variety of cationic residues.
Project 1: Sequence specificity recognition of green fluorescent protein by Q8
Targeting proteins by using short amino acid motifs in regions where the amino acids can be accessible is a great technique for protein analysis. Green fluorescent protein (GFP) is known for its stability, surface exposed N-terminus and intrinsic fluorescence therefore makes it easy to mutate a few residues at the N-terminus to study the interaction between that site on the GFP and Q8. Only the second and third residues will be mutated because GFP already possess a N-terminal methionine. This methionine cannot be cleaved off by N-terminal methionine aminopeptidase because the adjacent residues mutated have larger side chains. The desired GFP mutants will be expressed in E. coli, pET plasmid using established protocol of expression, and purification of the protein. The hypothesis is based on using a recombinant GFP with desired modification. This will provide a broad binding analysis of Q8 specificity on targeted amino acid motif on the flexible N-terminus of the protein.
Project 2: Sequence-predictive recognition of native protein by a synthetic receptor
The N-terminal recognition by Q8 can be applied to natural protein such as Nedd8 and p53. These proteins have one of the MXA peptides present at its N-terminal region. The Nedd8 is a ubiquitin-like protein which has methionine and leucine present in the N-terminal’s first and second position respectively. The p53 protein is a tumor-suppressor gene which is inactive in many cancers. Both p53 full length and D133p53 proteins will be cloned into pET11 plasmid and expressed in E. coli cells. After expression, the proteins will be purified via anion exchange chromatography and characterized using ESI-MS. ITC studies will be done on each protein in complex with Q8. Full length p53 will be used as a control to test any background binding. ESI-MS can also be used to determine the proteins and Q8 complex.We expect affinity and specificity results of D133p53-Q8 complex to be comparable to the peptide results from project 1.
Student Training Plan. Any undergraduate student who joins this lab will explore the fundamental of supramolecular chemistry related to the specific recognition of amino acid residues, peptides and proteins surfaces by synthetic molecules.
CONTACT INFORMATION
Email:
keturah.adams@swosu.edu Office Number: CPP 202-B
Phone Number: 580-774-6027
TEACHING: BASIC COURSES
SCI 1513 Concepts of Physical Science
SCI 1501 Concepts of Physical Science Lab
CHEM 1004 Gen Chem
CHEM 1004L Gen Chem Lab
CHEM 1203 Gen Chem I
CHEM 1252 Gen Chem
TEACHING: BIOCHEMISTRY
CHEM 4124 Biochemistry
CHEM 4124L Biochemistry Lab
CHEM 4133 Pharmaceutical Biochemistry
OTHER ACTIVITIES
AUG 2020-PRESENT
Chemistry Tutoring Coordinator
RECENT PUBLICATIONS
Kurra Y, Odoi KA, Lee YJ, Yang Y, Lu T, Wheeler SE, Torres-Kolbus J, Deiters A, & Liu WR. (2014 Sep 17). Two rapid catalyst-free click reactions for in vivo protein labeling oy genetically encoded strained alkene/alkyne functionalities. Bioconjugate Chem, 25(9), 1730-1738.
PMID: 25158039
doi: 10.1021/bc500361d
*Contributed equally
Odoi KA, Huang Y, Rezenom YH, & Liu WR. (2013). Nonsense and sense suppression abilities of original and derivative Methanosarcina mazei pyrrolysyl-tRNA synthetase-tRNA(Pyl) pairs in the Escherichia coli BL21(DE3) cell strain. PLos One, 8(3), e57035.
PMID: 23520461
doi: 10.1371/journal.pone.0057035
O’Donoghue P, Prat L, Heinemann IU, Ling J, Odoi KA, Huang Y, Liu WR, & Söll D. (2012). Near-cognate suppression of amber, opal and quadruplet codons competes with aminoacyl-tRNAPyl for genetic code expansion. FEBS Letters, 586(21), 3931-3937.
PMID: 23036644
doi: 10.1016/j.febslet.2012.09.033
