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.

Dr. Chang's teaching interests include analytical chemistry, biochemistry, writing and data presentation, literature analysis, and innovations in introductory chemistry.

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.

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.

My research focuses on the design, synthesis and evaluation of novel enzyme inhibitors.
Specifically, we are developing compounds that inhibit the activity of key enzymes (called 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 deliver inhibitory species to the active site.  Through this approach we hope to produce highly potent inhibitors that display enhanced affinity and specificity for their target enzymes.  Such compounds may serve as a template for the development of potential therapeutic agents.

My research interests have always centered on the transition metals and have encompassed both studies of structure and bonding in these complexes and the mechanisms of their reactions. At York, my research focused on bonding and structure in an unusual group of soluble transition metal polymers. For the last six years, I have been co-opted into administration and currently serve as Project Director of the York College McNair Scholars program and as Coordinator of Chemistry.

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.