The Cantor Nanoscience Lecture, organised by the York Nanocentre on an annual basis, was given this year by Nobel Prize winning structural biologist Dr Venkatraman Ramakrishnan. The lectures are open to the public and bring distinguished scientists to the University to discuss science at the nanoscale.
Dr Ramakrishnan was awarded the Nobel Prize (along with Thomas Steitz and Ada Yonath) for Chemistry in 2009 for his work on the elucidation of the structure of ribosomes.
The lecture titled, ‘How antibiotics illuminate ribosome function and vice versa’ was an account of Dr Ramakrishnan’s work in determining ribosome structure and how this knowledge can be used to develop effective new antibiotics.
Ribosomes are a vital part of the molecular machinery of cells, crucial to translating the genetic code of DNA and turning it into functional proteins. The ribosomes found in bacteria are different to those found in higher organisms such as humans, making them a useful target for antibacterial drugs. Bacterial ribosomes consist of two subunits, termed the 30S and 50S. Many antibiotics work by irreversibly binding to the 30S subunit thereby inhibiting protein synthesis and causing death of the bacteria.
Dr Ramakrishnan and his team used a technique known as X-ray crystallography (famous for its role in the discovery of the double helical structure of DNA) to determine the complete molecular structure of the 30S subunit and how it interacts with antibiotics.
Other than providing invaluable information about the workings of genetic mechanisms at a molecular level, this work paves the way for the development of new antibiotics.
Antibiotics are currently the only weapon available against bacterial infection and the need for new antibiotics is becoming ever more critical with the increased spread of antibiotic resistant bacteria such as MRSA. Currently, many strains of bacteria have developed resistance to all but one or two antibiotics. Armed only with our current array of antibiotics, it will not be long before diseases such as tuberculosis and cholera, once consigned to the scrap heap of history in developed countries, soon become untreatable killers again. The work of Dr Ramakrishnan and his team in determining the precise way in which antibiotics bind to ribosomes provides the possibility of manufacturing new antibiotics to prevent this from happening.