- NEW: The prize recognizes work on cells that tell scientists what is going on in the human body
- NEW: Their work has allowed drug makers to develop medication with fewer side effects
- Nobel Prizes in chemistry have often gone to life sciences
- Other work praised this week has deep implications for society
(CNN) -- Two American scientists won the Nobel Prize in chemistry for their work revealing protein receptors on the surface of cells that tell them what is going on in the human body. The achievements have allowed drug makers to develop medication with fewer side effects.
Over four decades of research by Robert J. Lefkowitz and Brian K. Kobilka on "G-protein-coupled receptors," have increased understanding of how cells sense chemicals in the bloodstream, according to the Royal Swedish Academy of Sciences, which awarded the prize.
"I'm feeling very, very excited," Lefkowitz said in a predawn phone call from the United States to the committee in Stockholm, Sweden. The announcement caught him by surprise.
"Did I even have any inkling that it was coming?" he said. "I'd have to say no."
Cell discovery earns Nobel Prize Lefkowitz, from the Howard Hughes Medical Institute and Duke University Medical Center, Durham, North Carolina, began tracking cell receptors in 1968, when he revealed "several receptors, among those a receptor for adrenalin."
In the 1980s, Kobilka, from Stanford University School of Medicine in California, joined the research to find the gene that produces the adrenalin receptor.
"In 2011, Kobilka achieved another break-through," the academy said in a news release: a photographic image of a hormone triggering a receptor to send an impulse into its cell.
"This image is a molecular masterpiece -- the result of decades of research," the academy said.
Nobel Prizes in chemistry have gone to predominantly to organic or carbon-based chemistry, particularly to discoveries in the area of life sciences, such as genetics.
This year's monetary award will be 8 million Swedish kronor (about $1.2 million). This represents a drop of 20%, compared with last year, from 10 million Swedish kronor, and is due to the turbulence that has hit financial markets.
Last year, Israeli scientist Daniel Shechtman from Technion - Israel Institute of Technology won the award for the discovery of quasicrystals, which was made in 1982 and "fundamentally altered how chemists conceive of solid matter," according to the Royal Swedish Academy of Sciences.
Read more: Frenchman, American win Nobel Prize in physics
On Tuesday, the academy bestowed Nobel honors in physics on Serge Haroche of France and David Wineland of the United States for their work in quantum optics that allowed scientists to observe the workings of atoms without disturbing their properties. As a side effect, their work lays down principles that could lead to quantum computers, which are astronomically fast computers that would radically change human life, if ever invented.
On Monday, the Nobel Assembly awarded the prize for physiology or medicine to Sir John B. Gurdon and Shinya Yamanaka jointly for their discovery that stem cells can be made of mature cells and need not necessarily be taken from fetuses or embryos.
Read more: Nobel Prize in medicine awarded for groundbreaking cell research
The committee also will announce prizes in literature, peace and economics.
Since 1901, the committee has handed out the Nobel Prize in chemistry 103 times. In certain years, mainly during World Wars I and II, no prize in chemistry was awarded.
The youngest recipient was Frederic Joliot, who won in 1935 at the age of 35. The oldest chemistry laureate was John B. Fenn, who was 85 when he received the prize in 2002.
Frederic Sanger was the only scientist to win the chemistry prize twice for his work related to the structure of proteins and DNA.
There is a fine line between the science of chemistry and the fields of physics and biology. Famed female scientist Marie Curie of France, for example, won Nobel honors for her work in radiophysics in 1903 and then again in 1911 for discoveries in radiochemistry.
