The main research topic in our group
is the study of conformational changes of biological
macromolecules (proteins, DNA). The goal is to understand the physical
principles underlying the internal organization of these molecules
and their mutual interactions, which translate into their function.
This also leads to designing our own artificial nanomachines.
We use nanomechanical and optical techniques to study conformational
changes of single bio-molecules. Single molecule experiments
are advantageous for exploring the dynamics.
Through ensemble experiments we study equilibrium properties
and engineer new devices at the nm scale. For example, one mechanical
component which, unlike nuts and bolts, can be shrunk to the
nanoscale is the spring. By inserting a “molecular spring” on
a protein we can control the protein’s conformation, and
thus its function. We create artificial molecular devices based
on allosteric control.
DNA is the molecule which encodes the masterplan
for the cell. Decoding this information, i.e. the process of expressing
and controlling genes, involves a variety of conformational changes
of DNA caused by protein - DNA interactions.
Proteins are the molecular machines which perform
the tasks in the living cell. This includes catalysis, molecular
recognition, and mechanical motion. Virtually all these tasks
involve a change of conformation of the protein. Allosteric
control, whereby a chemical signal modifies a protein’s
conformation, is the molecular basis of life.
Research in the Zocchi Lab is
supported / has been supported by:
The National Science Foundation / DMR ; the US-Israel Binational Science Foundation
; the US Department of Defense / DMEA
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Proteins
are soft – can
undergo large reversible deformations. Mechanical forces naturally
couple to such conformational changes. With the molecular springs,
we have introduced an ensemble method to exert localized mechanical
forces on proteins. Technically, this allows for high-throughput
experiments and for the construction of devices. Conceptually,
we have learned how to establish a field – the force field – which
naturally couples to the relevant degrees of freedom of the protein.
Usually this leads eventually to the discovery of new effects
and a better understanding of the physics of the system |