Tag Archives: protein crystallography

3-D ‘Map’ of Enzyme Completed by MU Scientists Could Lead to More Effective Drugs

Enzyme map created by using a high-powered X-ray device

COLUMBIA, Mo. – The human body is full of proteins called enzymes that help nearly every function in the body. Scientists have been studying enzymes for decades in order to learn how they work and how to create better drugs and medical treatments for many ailments. Now, University of Missouri researchers have completed a 3-D map of an enzyme called Proline utilization A (PutA). PutA facilitates metabolism by adding oxygen to molecules. John Tanner, a professor in the MU Department of Biochemistry, says mapping this enzyme will give researchers a better understanding of its function, which could help drug manufacturers create more effective drugs. (more…)

Read More

How a Microbial Biorefinery Regulates Genes

Digesting lignin, a highly stable polymer that accounts for up to a third of biomass, is a limiting step to producing a variety of biofuels. Researchers at Brown have figured out the microscopic chemical switch that allows Streptomyces bacteria to get to work, breaking lignin down into its constituent parts.

PROVIDENCE, R.I. [Brown University] — Microorganisms that can break down plant biomass into the precursors of biodiesel or other commodity chemicals might one day be used to produce alternatives to petroleum. But the potential of this “biorefinery” technology is limited by the fact that most microorganisms cannot break down lignin, a highly stable polymer that makes up as much as a third of plant biomass.

Streptomyces bacteria are among few microorganisms known to degrade and consume lignin. Now a group of researchers at Brown University has unlocked the genetic and molecular mechanisms behind a key part of that process. The results are published in the journal Nucleic Acids Research. (more…)

Read More

A New Way of Looking at Photosystem II

Berkeley Lab and SLAC Researchers Study Key Protein Complex Crucial to Photosynthesis

Future prospects for clean, green, renewable energy may hinge upon our ability to mimic and improve upon photosynthesis – the process by which green plants, algae and some bacteria convert solar energy into electrochemical energy. An artificial version of photosynthesis, for example, could use sunlight to produce liquid fuels from nothing more than carbon dioxide and water. First, however, scientists need a better understanding of how a large complex of proteins, called photosystem II, is able to split water molecules into oxygen, electrons and hydrogen ions (protons). A new road to reaching this understanding has now been opened by an international team of researchers, led by scientists at the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) and SLAC National Accelerator Laboratory.

Using ultrafast, intensely bright pulses of X-rays from SLAC’s Linac Coherent Light Source (LCLS), the research team produced the first ever images at room temperature of microcrystals of the photosystem II complex. Previous imaging studies, using X-rays generated via synchrotron radiation sources, required cryogenic freezing, which alters the samples. Also, to catalyze its reactions, photosystem II relies upon an enzyme that contains a manganese-calcium cluster that is highly sensitive to radiation. With the high-intensity femtosecond X-ray pulses of the LCLS, the research team was able to record intact images of these clusters before the radiation destroyed them. (more…)

Read More