Ribosomes are complex, bead-like structures, which exist in multiple copies in each cell. In one of life’s core processes, the ribosome translates the DNA code into life, producing the tens of thousands of different proteins that in turn control the chemistry in all living organisms. The genetic instructions from DNA are encoded on a ‘template’ called messenger RNA (mRNA). Ribosomes work along mRNA reading the code needed to produce specific proteins. In order for proteins to be generated at the speed and quantity required, a number of ribosomes work simultaneously along each mRNA strand. An understanding of how ribosomes work is crucial for a scientific understanding of life.

Venki Ramakrishnan started work on the structure of the ribosome at the University of Utah, before moving to the MRC Laboratory of Molecular Biology in 1999. Using X-ray crystallography to determine the position of the hundreds of thousands of atoms that make up a ribosome, the structure of the entire ribosome was solved. It is the most complex atomic-resolution structure determined to date. This research shed light on the role of the ribosome in the decoding of mRNA and on antibiotic function, showing how different antibiotics bind to ribosomes.

This information is critical in developing new antibiotics to combat infection and disease. Modern antibiotics work by blocking the function of bacterial ribosomes: if the ribosomes cannot work, bacteria cannot survive.

The knowledge about ribosomes opens up the possibilities of more medical advances and applications in the future. Venki’s group continue their studies on ribosomes, at the LMB, to further understand the detailed mechanisms involved in the process of protein synthesis.

Venki shared the Nobel Prize with Thomas Steitz from Yale University and Ada Yonath from the Weizman Institute.

The human body consists of hundreds of cell types, all originating from the fertilized egg. During the embryonic period, the number of cells increases dramatically. They mature and become specialized to form the various tissues and organs of the body. Large numbers of cells continue to be formed in the adult body. In parallel with the generation of new cells, cell death is a normal process, both in the foetus and adult, to maintain the appropriate number of cells in tissues. This delicate, controlled elimination of cells is called programmed cell death.

Sydney Brenner, Bob Horvitz and John Sulston, studied how genes regulate organ development and how cells are programmed to die. By studying the life cycle of the adult nematode worm, which has just 959 cells, a short lifetime, and is transparent, it was possible to follow cell division as it happened, and ‘map’ these cells to identify the origin of the worm’s components during development. It was also possible to see what effects gene mutations had on organ development. Studying programmed cell death is important in understanding how viruses and bacteria invade cells and cancer changes them. Inducing such death is a key goal of cancer therapy.

Collaborating with Bob Waterston, John then moved onto sequencing the worm’s genome, reading the DNA code that determines the characteristics of the worm. This work led to the sequencing of the human genome, with John leading the UK team at the Wellcome Trust Sanger Institute. Using sequencing techniques developed by Fred Sanger, the human genome was completed in 2003. This is now being studied in order to improve the diagnosis of disease, develop new therapies and improve healthcare. The more we learn about the human genome the more there is to explore.

ATP – adenosine triphosphate – provides the fuel for life in all organisms from bacteria and fungi to plants and man. It captures the energy in foodstuffs and uses it in building cellular components such as DNA and proteins, in muscle contraction, in transmission of nerve messages and in many other processes.

In the late 1970s, John Walker began his studies of ATP synthase, a molecular machine that is the key enzyme in cellular energy conversion. He realized that a detailed knowledge was required in order to understand how it works. Therefore, he isolated the molecular machine involved in the production of ATP from the mitochondria, the power-houses in our cells. He characterized its many component parts and showed how it is constructed from them. This work led to the realization that the machine is driven by a mechanical rotary mechanism, a new principle in enzyme function. This discovery opened up new areas of chemical research as well as providing the basis for biomedical applications for the benefit of mankind.

The study of the process of energy conversion in biology continues at the MRC Mitochondrial Biology Unit, on the Addenbrooke’s site. Here, John Walker and other researchers are focused on understanding the biochemical and biological processes which occur in mitochondria, studying energy conversion in man and its involvement in human conditions such as aging, obesity and neuromuscular and neurodegenerative diseases, with the aim of eventually producing new therapies.

John shared the Nobel Prize with Paul Boyer from the University of California, Los Angeles, and Jens Skou from Aarhus University.

Antibodies are Y shaped molecules with two flexible arms. The detailed shape of the ends of the arms varies from one molecule to another, so providing a wide range of antigen binding sites. The ability of antibodies to bind specifically to substances is very useful in medical research, but it was difficult to produce large quantities of specific antibodies in the laboratory. The human immune system can produce more than two million different antibodies, each of which can recognize, bind to and destroy just one specific antigen.

César Milstein and Georges Köhler were trying to understand the mechanisms responsible for the remarkable diversity of antibodies. Through this research, they invented a way to stimulate cells to provide unlimited production of a specific antibody – a monoclonal antibody. It was recognized that monoclonal antibodies had the potential to diagnose and treat a wide array of diseases, but it would take twenty years before this approach could be applied to humans, following research led by Greg Winter and Michael Neuberger at the MRC Laboratory of Molecular Biology.

One of the most successful ways in which monoclonal antibodies have been used is in diagnostics – “tagging” a monoclonal with a fluorescent dye to see if it has attached to a specific antigen. This method can be used to diagnose cancers and AIDS. Monoclonal Antibodies are now also being used for therapies to treat diseases including rheumatoid arthritis, multiple sclerosis, some forms of cancer and viral infections. It has sparked an international multi-billion pound biotechnology industry: monoclonal antibodies are the basis of a third of all biotech products in clinical development.

César and Georges shared the Nobel Prize with Niels Jerne from the Basel Institute, Switzerland.

Electron microscopy has long been used to obtain two-dimensional (2D) pictures of biological objects. An electron microscope uses electrons to illuminate a specimen and create an enlarged image. They have much greater resolving power than light microscopes and can magnify specimens up to two million times, while the best light microscopes are limited to magnifications of 2,000 times. But unlike the light microscope, the electron microscope cannot be focused to view different levels: all the 3D matter in the line of view is projected into a 2D image.

Aaron Klug overcame this limitation by taking images in different directions and combining them mathematically, using computers, to produce the 3D structure. He initially used this to determine the structure of viruses before studying the combination of protein and DNA in chromatin, of which chromosomes are made. Chromatin was broken into small fragments that could be examined. A model for chromatin was then proposed based on this knowledge of the structure of the fragments. The exact structure of chromatin affects how the genetic code along the DNA is read. This investigation is crucial in the understanding of cancer, in which the control of growth and division of cells by the genetic material no longer works.

Since the invention of 3D reconstruction, improvements in electron microscopes, in specimen preparation and in computers have led to huge advances in 3D microscopy and suitable specimens, such as viruses, can now be visualised in atomic detail. Sub-cellular structures can now be imaged by electron tomography and similar approaches have revolutionised medical imaging, where CT scanning is now used routinely in the diagnosis of neurological diseases and cancers.

Following his work on proteins, Fred Sanger became interested in developing a technique to determine the exact sequence of the building blocks in DNA – called bases. Due to the very large size of DNA molecules, the problem was finding a rapid and simple method to determine sequences.

Fred initially developed methods to find out the genetic sequence of a virus, which had just over 5000 base pairs and was the first fully sequenced genome. This method was then extended to determine the much larger sequence of human DNA, and this was the most widely used analysis method from the early 1980s. Fred’s method relies on copying the DNA sequence, but it stops copying every time it hits a particular DNA base – of which there are only four types – A, C, G and T. By measuring the length of the incomplete copies, you can determine where that base occurs in the DNA. This sequence is read off an autoradiograph, a photographic record of a biological specimen, and gives a characteristic ‘striped’ pattern.

Fred’s method shaped the way that genomics and biomedicine were explored and was key to the Human Genome Project, an international collaboration to identify all the approximately 20,000-25,000 genes in human DNA. This has increased the understanding of many genetically based diseases including cancer. Knowledge about the effects of DNA variations among individuals can lead to revolutionary new ways to diagnose, treat, and eventually prevent the thousands of disorders that affect us. Differences at the DNA level between people are also the basis of DNA fingerprinting.

Fred shared the Nobel Prize with Walter Gilbert, at Harvard University, and Paul Berg at Stanford University.

The long chains of amino acids that make up proteins are coiled into specific three-dimensional configurations to give each protein its unique properties. In order to understand their function, it is vital to know their physical structure, as well as their chemical structure.

Inspired to start work on protein structure, Max Perutz, at the MRC Unit for Research on the Molecular Structure of Biological Systems (now the MRC Laboratory of Molecular Biology) chose haemoglobin, the red pigment of blood whose major function is the transport of oxygen from the lungs to the tissues. Consisting of four chains, it is, at the molecular level, a large protein. It took 25 years for its structure to be determined. John Kendrew joined Max at the Unit and started work on a related, but smaller protein, myoglobin. Myoglobin consists of just one chain, and is present in the muscle of mammals such as whales and seals, where it acts as an oxygen store during diving. In 1959 it became the first protein to have its three-dimensional structure determined. The haemoglobin structure followed just a few months later.

Max and John developed the technique of protein crystallography, which uses the way that crystals of proteins cause X-rays to change direction to produce unique patterns from which their structures can be established. This technique is now used worldwide to determine the structure of large molecules. Determining the structure and function of proteins helps us to understand malfunctioning proteins, which cause illnesses, such as sickle cell anaemia, and helps develop treatments for these. The MRC Laboratory of Molecular Biology has major programmes on protein structure, harnessing techniques that rely on complex technologies.

DNA, deoxyribonucleic acid, is the genetic material of organisms and is responsible for the transmission of hereditary characteristics, e.g. eye and hair colour. Many disabilities and illnesses, including some cancers, can also be linked to your DNA. Finding the structure of DNA was the first step to understanding how these features are transferred from parents to offspring.

Francis and Jim were working on solving the structure of DNA in the MRC Unit for Research on the Molecular Structure of Biological Systems (now the MRC Laboratory of Molecular Biology). Using experimental data, especially X-ray diffraction photographs from Rosalind Franklin and Maurice Wilkins at King’s College, London, they began the process of model building.

They showed how the different components of DNA interact in three dimensions to form a long spiraling molecule, with a double ‘backbone’ of sugar and phosphates. Nitrogen-containing compounds, called bases, protrude from the two halves of the backbone and link together in pairs, so the whole molecule is like a zip. This is known as the double helix. The four types of bases form a sequence along the DNA, and this is the ‘genetic code’ from which the whole body develops.

The discovery immediately suggested the way in which DNA is replicated: the two strands are ‘unzipped’ to allow the ‘code’ of bases to be copied. “It is this specific pairing between bases that is the heart of the replication process”. The unraveling of the helical structure of DNA is hailed as one of the most significant landmarks of the 20th century.

Scientists have been able to build on this basic knowledge of DNA, by applying it to issues of health and medicine, e.g. identifying ‘faulty’ genes, such as the cystic fibrosis gene and the BRCA1 and BRCA2 genes implicated in some breast cancers.

Francis and Jim shared the Nobel Prize with Maurice Wilkins.

Every function in a living cell depends on proteins. They are complex organic compounds that play a central role in the structure and functioning of living cells. They include: structural proteins, e.g. in muscle; enzymes which are catalysts for reactions in the body, e.g. in metabolism; and specialist molecules e.g. haemoglobin. Proteins consist of molecules called amino acids linked into long chains.

For the first of his two Nobel Prizes in chemistry, Fred Sanger determined the entire sequence of the 51 amino acids in the protein insulin, and showed how they are linked together. Insulin is an important natural hormone, which controls the level of glucose (sugar) in the blood, and is used in the treatment of diabetes. Fred’s method involved separating the different fragments of the protein on filter paper and moving them with an electric current according to their electric charge. This created a distinct pattern on the paper, which Fred called a ‘fingerprint.’ The information about these fragments then had to be reconstructed – like a puzzle – in the correct order to give the sequence or ‘chemical structure.’

After 12 years of dedicated research, this was the first time the chemical structure of a protein had been deduced. It demonstrated that the sequence of amino acids in protein chains determines the individual and physiological properties of the protein. Fred’s methods could now be applied to proteins in general to explore their role as key substances for life. Today, it is still necessary to use chemical means to determine protein sequences.