Assistant Professor of Chemistry
email: chrischang@berkeley.edu
office: 532A Latimer
lab: 401, 535/541, 549 Latimer
phone: 510.642.4704
fax: 510.642.7301
lab phone: 510.643.9522 and 510.643.4160
Research Group URL
Recent Publications
Research Interests
Bioinorganic Chemistry, Inorganic and Organic Chemistry, Molecular Biology, and Chemical Biology.
Molecular imaging sensors for the neurosciences and immunology, metal catalysts for renewable energy cycles and green chemistry.
Our laboratory uses a combination of inorganic and organic chemistry, molecular biology, and chemical biology approaches to explore new frontiers of science, with particular interest in the areas of neuroscience, immunology, energy research, and green chemistry. A signature of our program is the ability to design and make new molecules for a targeted function. Because the motivation to create new molecular systems is driven by wanting to answer specific questions of interest, this problem-based, make-and-measure approach to research allows students and postdocs in the group to take their own projects from start to finish. We synthesize a wide variety of molecules ranging from small organics to inorganic and organometallic transition-metal and lanthanide coordination complexes, as well as generate new protein constructs and nanomaterial conjugates. With these novel molecular systems in hand, we utilize a battery of spectroscopic and structural characterization techniques, mechanistic reaction chemistry and catalysis, functional protein and nucleic acid assays, and/or biological imaging to evaluate their properties and applications. Four main project areas are under current investigation.
Chemical Neurobiology: Metals on the Brain. Neuroscience is an exciting and important scientific frontier, and understanding the molecular chemistry of the brain is essential for unlocking the secrets of basic neurological functions such as learning, memory, motor control, and senses, as well as diagnosing and treating neurodegenerative diseases like Alzheimer's and Parkinson's. We are particularly interested in the bioinorganic chemistry of the brain. The brain requires the highest amounts of copper and iron in the human body for normal function, but levels of these redox-active metals rise with aging, causing uncontrolled disruptions of metal homeostasis that can lead to oxidative damage and aggregation of proteins and subsequent neuronal death. In particular, Alzheimer's and Parkinson's diseases are characterized by protein-derived plaques that accumulate unusually high amounts of abnormally distributed copper and iron compared to normal brain tissue. To study contributions of metal balance to brain function in various stages of health and disease, we are developing and applying new imaging sensors and related chemical tools to interrogate, in real time, molecular aspects of cellular metal accumulation, trafficking, and redox function.
Chemical Neurobiology: Oxidation Biology. The brain is the body's most oxidatively active organ, consuming over 20% of the oxygen we breathe in every day. On the other hand, many diseases associated with aging and the brain, including cancer and neurodegenerative diseases such as Alzheimer's and Parkinson's, have a strong oxidative stress component stemming from cellular oxygen mismanagement. Oxidative stress is the result of unregulated production of reactive oxygen species, and accumulation of oxidative damage over time leads to the functional decline of organ systems. The biology of reactive oxygen species is much more complex, however, as emerging evidence shows that small oxygen metabolites, such as hydrogen peroxide, can mediate beneficial cellular signal transduction cascades when produced in the right place at the right time at appropriate levels. We are developing and applying new fluorescent, luminescent, and magnetic resonance imaging (MRI) probes for reactive oxygen species, redox status, and enzyme activity to study molecular mechanisms of oxidative signaling and stress pathways in living cells, tissue, and organisms.
Metals in Immunology. The interface between inorganic chemistry and immunology represents a rich and open area for investigation, as infectious pathogens and human hosts alike share a common need for metals like copper, iron, and zinc for their survival, growth, and development. Because these essential nutrients cannot be synthesized but must be acquired and stored, unraveling the molecular details of this metal tug-of-war between invading microbial pathogens and potential hosts represents a significant scientific challenge. We are interested in understanding, at the molecular level, how dynamic changes in metal homeostasis pathways of the host and pathogen influence the innate immune response, pathogenicity, and virulence. Molecular imaging provides an attractive approach for studying such host-pathogen interactions in real time.
Renewable Energy Catalysis and Green Chemistry. A grand challenge facing our global future is energy. By 2050, the planet's energy needs will almost triple from 12.8 to 35 TW, with carbon dioxide levels at the highest they've been in the last 650,000 years. These issues of climate change and energy demand require the development of new, sustainable energy technologies that are carbon neutral, and basic science is needed to meet this ultimate goal. An important aspect of this effort is catalysis, which will allow the efficient storage and transformation of energy in the form of chemical fuels. We are focused on devising new synthetic inorganic and organometallic systems that utilize cheap and abundant metals, particularly those of the first-row transition metal series, which will have reduced environmental impact. One major goal is to develop stoichiometric and catalytic reactions towards water, oxygen, hydrogen, carbon dioxide, and other small molecules of energy consequence that work in benign solvents such as water. In another avenue of research, we are also targeting fundamental aspects of metal-ligand multiple bonding and small-molecule activation using first- and/or second-sphere coordination chemistry approaches.
Biography
Assistant Professor; B.S./M.S. California Institute of Technology (1997); Fulbright Fellow Université Louis Pasteur (1997-1998); Ph.D. Massachusetts Institute of Technology (2002); National Science Foundation Predoctoral Fellow (1998-2001); M.I.T./Merck Foundation Predoctoral Fellow (2001-2002); Jane Coffin Childs Postdoctoral Fellow, Massachusetts Institute of Technology (2002-2004); Davison Thesis Prize (Massachusetts Institute of Technology, 2003); Camille and Henry Dreyfus Foundation New Faculty Award (2004); Arnold and Mabel Beckman Foundation Young Investigator Award (2005); American Federation for Aging Research Award (2005); National Science Foundation CAREER Award (2006); Packard Fellowship for Science and Engineering (2006); Alfred P. Sloan Fellowship; American Chemical Society Organic Young Investigator (2007); Paul Saltman Award, Metals in Biology GRC (2008); Amgen Young Investigator Award (2008); Hellman Faculty Award (2008); Bau Award in Inorganic Chemistry, Chinese Academy of Sciences (2008); Technology Review TR35 Young Innovator Award (2008); Howard Hughes Medical Institute Investigator (2008).