Cornelius Van Niel
Encyclopedia
Cornelis Bernardus van Niel (November 4, 1897, Haarlem
– March 10, 1985, Carmel, California
) was a Dutch
-American
microbiologist
. He introduced the study of general microbiology to the United States and made key discoveries explaining the chemistry
of photosynthesis
.
In 1923, Cornelis van Niel married Christina van Hemert, graduated in chemical engineering at Delft University and became an assistant to Albert Jan Kluyver, who had initiated the field of comparative biochemistry. In 1928 he wrote his PhD dissertation ('The Propionic Acid
Bacteria') after which he left for the United States to continue his work at the Hopkins Marine Station
of Stanford University
.
By studying purple sulfur bacteria
and green sulfur bacteria
he was the first scientist to demonstrate that photosynthesis is a light-dependent redox
reaction, in which hydrogen
from an oxidizable compound reduces carbon dioxide
to cellular materials. Expressed as:
His discovery predicted that H2O is the hydrogen donor in green plant photosynthesis and is oxidized to O2. The chemical summation of photosynthesis was a milestone in the understanding of the chemistry of photosynthesis. This was later shown to be by Robert Hill.
Esther Lederberg
was one of C. B. van Niel's accomplished students, as was Allan Campbell
. For one of Esther Lederberg's interesting anecdotes about C. B. van Niel, see http://www.EstherLederberg.com/Anecdotes.html#HMSFRIENDS.
In 1961, Van Niel in collaboration with R.Y. Stanier
defined prokaryotes as cells in which the nuclear material is not surrounded by a nuclear membrane, a definition that is still used to date. He received the American National Medal of Science
in 1963.
Haarlem
Haarlem is a municipality and a city in the Netherlands. It is the capital of the province of North Holland, the northern half of Holland, which at one time was the most powerful of the seven provinces of the Dutch Republic...
– March 10, 1985, Carmel, California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
) was a Dutch
Netherlands
The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...
-American
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
microbiologist
Microbiologist
A microbiologist is a scientist who works in the field of microbiology. Microbiologists study organisms called microbes. Microbes can take the form of bacteria, viruses, fungi, and protists...
. He introduced the study of general microbiology to the United States and made key discoveries explaining the chemistry
Chemistry
Chemistry is the science of matter, especially its chemical reactions, but also its composition, structure and properties. Chemistry is concerned with atoms and their interactions with other atoms, and particularly with the properties of chemical bonds....
of photosynthesis
Photosynthesis
Photosynthesis is a chemical process that converts carbon dioxide into organic compounds, especially sugars, using the energy from sunlight. Photosynthesis occurs in plants, algae, and many species of bacteria, but not in archaea. Photosynthetic organisms are called photoautotrophs, since they can...
.
In 1923, Cornelis van Niel married Christina van Hemert, graduated in chemical engineering at Delft University and became an assistant to Albert Jan Kluyver, who had initiated the field of comparative biochemistry. In 1928 he wrote his PhD dissertation ('The Propionic Acid
Propionic acid
Propanoic acid is a naturally occurring carboxylic acid with chemical formula CH3CH2COOH. It is a clear liquid with a pungent odor...
Bacteria') after which he left for the United States to continue his work at the Hopkins Marine Station
Hopkins Marine Station
Hopkins Marine Station is the marine laboratory of Stanford University. It is located ninety miles south of the university's main campus, in Pacific Grove, California on the Monterey Peninsula, adjacent to the Monterey Bay Aquarium. It is home to nine research laboratories and a fluctuating...
of Stanford University
Stanford University
The Leland Stanford Junior University, commonly referred to as Stanford University or Stanford, is a private research university on an campus located near Palo Alto, California. It is situated in the northwestern Santa Clara Valley on the San Francisco Peninsula, approximately northwest of San...
.
By studying purple sulfur bacteria
Purple sulfur bacteria
The purple sulfur bacteria are a group of Proteobacteria capable of photosynthesis, collectively referred to as purple bacteria. They are anaerobic or microaerophilic, and are often found in hot springs or stagnant water. Unlike plants, algae, and cyanobacteria, they do not use water as their...
and green sulfur bacteria
Green sulfur bacteria
The green sulfur bacteria are a family of obligately anaerobic photoautotrophic bacteria. Most closely related to the distant Bacteroidetes, they are accordingly assigned their own phylum....
he was the first scientist to demonstrate that photosynthesis is a light-dependent redox
Redox
Redox reactions describe all chemical reactions in which atoms have their oxidation state changed....
reaction, in which hydrogen
Hydrogen
Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...
from an oxidizable compound reduces carbon dioxide
Carbon dioxide
Carbon dioxide is a naturally occurring chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom...
to cellular materials. Expressed as:
- 2 H2A + CO2 → 2A + CH2O + H2O
His discovery predicted that H2O is the hydrogen donor in green plant photosynthesis and is oxidized to O2. The chemical summation of photosynthesis was a milestone in the understanding of the chemistry of photosynthesis. This was later shown to be by Robert Hill.
Esther Lederberg
Esther Lederberg
Esther Miriam Zimmer Lederberg was an American microbiologist and immunologist and pioneer of bacterial genetics...
was one of C. B. van Niel's accomplished students, as was Allan Campbell
Allan Campbell
Allan M. Campbell is an American microbiologist and geneticist whose pioneering work on Lambda phage has helped advance molecular biology in the late 20th century.Dr...
. For one of Esther Lederberg's interesting anecdotes about C. B. van Niel, see http://www.EstherLederberg.com/Anecdotes.html#HMSFRIENDS.
In 1961, Van Niel in collaboration with R.Y. Stanier
Roger Stanier
Roger Yate Stanier was a Canadian microbiologist who was influential in the development of modern microbiology. As a member of the Delft School and former student of C. B. van Niel, he made important contributions to the taxonomy of bacteria, including the classification of blue-green algae as...
defined prokaryotes as cells in which the nuclear material is not surrounded by a nuclear membrane, a definition that is still used to date. He received the American National Medal of Science
National Medal of Science
The National Medal of Science is an honor bestowed by the President of the United States to individuals in science and engineering who have made important contributions to the advancement of knowledge in the fields of behavioral and social sciences, biology, chemistry, engineering, mathematics and...
in 1963.