Faculty / Staff
My research is centered on investigating the structural and dynamical aspects of protein-small molecule interactions using techniques such as vibrational spectroscopy and T-jump relaxation. One aspect of the work is to understand enzyme-substrate interactions which have long been recognized as representing an extreme expression of structural complementarities in biological chemistry. Basic research geared towards understanding the inner workings of an enzyme system is important if cures for the diseases caused by a malfunctioning or deficient enzyme are to be found. Our group is investigating the hydride transfer mechanism involved in the enzyme dihydropteridine reductase. DHPR is important in the normal cycling of tetrahydrobiopterin, an essential cofactor in the synthesis of serotonin and cathecholamine precursors. Regulation of DHPR became of interest with the discovery of atypical phenylketonuria, a neurological disorder associated with a defect in tetrahydrobiopterin recycling.
Research in the lab of Emmanuel Chang centers around biological applications of mass spectrometry. Our major interest is in analysis and methods development for protein phosphorylation and other post-translational modifications. Applications include phosphorylation in cell cycle; ADP-ribosyltaion; mass spectrometry-based biosensors, and kinase inhibitors and enzyme kinetics. We also collaborate with other CUNY and external scientists who would like to harness the power of mass spectrometry to study there own interesting biological systems.We supplement our experimental work with computational methods including bioinformatic protein sequence analysis and molecular modeling.
Dr. Chang's teaching interests include analytical chemistry, biochemistry, writing and data presentation, literature analysis, and innovations in introductory chemistry.
As a synthetic organic chemist, my research involves development of new methodology for the construction of bioactive natural products: alkaloids, cyclic ether arrays, & C-glycosides. Current studies include:
• Investigation & use of oxazolone as a useful heterocyclic scaffold for alkaloid synthesis - studies of intramolecular Diels-Alder reactions with oxazolone as dienophile.
• Novel organosilane chemistry for approaches to bioactive ethers - concise assembly of cis-fused bicyclic ether arrays via intramolecular attack of vinylsilanes at tethered oxocarbenium ions. A related silyl-activated Friedel-Krafts process requires an unusual combination of electronic & steric effects.
Recently completed targets include 2-epi-pumiliotoxin C & deoxyaltholactone. Similar approaches to gephyrotoxin & dysiherbaine are underway.
We spent many years studying the high resolution electronic spectroscopy of porphyrins. Recently, however we began to study the dynamics and thermodynamics associated with the formation of RNA construct-peptide complexes using single molecule detection methods, such as dual color fluorescence correlation spectroscopy (DCFCS) and single pair fluorescence resonance energy transfer (spFRET).
My research interest includes the development of a new drug delivery system which can target a specific organ, collect useful physiological data and release drugs when a light signal is given.
Currently there are two main areas of investigation being pursued in my laboratory.
1) Amyloid Formation and Protein Aggregation. The abnormal formation of protein aggregates, or amyloid deposits, is the hallmark of Alzheimer’s disease as well as Type 2 diabetes. My laboratory is investigating the molecular interactions that occur between key proteins that contribute to the formation of amyloid in these diseases. Through a more detailed understanding of how these proteins self-assembly to form aggregates, we hope to design and develop inhibitors which may serve as a template for potential therapeutic agents.
2) Protein Kinase Inhibitors. We are developing compounds that inhibit the activity of key enzymes (kinases) which can cause tissues to grow out of control and develop into tumors. To do this we are synthesizing molecules that exploit the unique molecular recognition motifs found in these enzymes to more effectively deliver inhibitory species to the active site.
I study gas phase molecular reaction dynamics, vibrational energy transfer, photodissociation, chemical reactions, and the spectroscopy of gases using cavity ring-down spectroscopy, a laser-based technique. I am currently working on the weak absorption in the visible of hydrogen and its isotopomers.
Teltingdiaz, Martin, Adjunct Associate Professor