Cornelis Bernardus van Niel (also known as Kees van Niel) (November 4, 1897 – March 10, 1985) was a Dutch-American

microbiologist A microbiologist (from Greek ) is a scientist who studies microscopic life forms and processes. This includes study of the growth, interactions and characteristics of microscopic organisms such as bacteria, algae, fungi, and some types of par ...

. He introduced the study of general

microbiology Microbiology () is the scientific study of microorganisms, those being unicellular (single cell), multicellular (cell colony), or acellular (lacking cells). Microbiology encompasses numerous sub-disciplines including virology, bacteriology, ...

to the United States and made key discoveries explaining the chemistry of

photosynthesis Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that, through cellular respiration, can later be released to fuel the organism's activities. Some of this chemical energy is stored i ...

Early life

In 1923, Cornelis van Niel graduated in chemical engineering at

Delft University Delft University of Technology ( nl, Technische Universiteit Delft), also known as TU Delft, is the oldest and largest Dutch public university, public Institute of technology, technical university, located in Delft, Netherlands. As of 2022 it is r ...

and became an assistant to

Albert Kluyver Albert Jan Kluyver ForMemRS (June 3, 1888 – May 14, 1956) was a Dutch microbiologist and biochemist. Career In 1926, Kluyver and Hendrick Jean Louis Donker published the now classic paper, "Die Einheit in der Biochemie" ("Unity in Biochemist ...

, who had initiated the field of comparative biochemistry. In 1925 he married Christina van Hemert in Bloemendaal, North Holland, Netherlands. In 1928 he wrote his PhD dissertation ('The

Propionic Acid Propionic acid (, from the Greek words πρῶτος : ''prōtos'', meaning "first", and πίων : ''píōn'', meaning "fat"; also known as propanoic acid) is a naturally occurring carboxylic acid with chemical formula CH3CH2CO2H. It is a li ...

Bacteria') after which he left for the United States to continue his work at the

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 (United States) on the Monterey Peninsula, adjacent to the Monterey Bay Aquar ...

of Stanford University.

Work and discoveries

Photosynthesis (1931)

By studying

purple sulphur bacteria The purple sulfur bacteria (PSB) are part of a group of Pseudomonadota capable of photosynthesis, collectively referred to as purple bacteria. They are anaerobic or microaerophilic, and are often found in stratified water environments including h ...

and green sulphur bacteria he was the first scientist to demonstrate, in 1931, that photosynthesis is a light-dependent

redox Redox (reduction–oxidation, , ) is a type of chemical reaction in which the oxidation states of substrate (chemistry), substrate change. Oxidation is the loss of Electron, electrons or an increase in the oxidation state, while reduction ...

reaction in which

hydrogen Hydrogen is the chemical element with the symbol H and atomic number 1. Hydrogen is the lightest element. At standard conditions hydrogen is a gas of diatomic molecules having the formula . It is colorless, odorless, tasteless, non-toxic ...

from an oxidizable compound reduces

carbon dioxide Carbon dioxide ( chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon dioxide is t ...

to cellular materials. Expressed as: :2 H₂A + CO₂ → 2A + CH₂O + H₂O where A is the

electron acceptor An electron acceptor is a chemical entity that accepts electrons transferred to it from another compound. It is an oxidizing agent that, by virtue of its accepting electrons, is itself reduced in the process. Electron acceptors are sometimes mist ...

. 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 experimentally verified by Robert Hill. In a nutshell, van Niel proved that plants give off oxygen as a result of splitting water molecules during photosynthesis, not carbon dioxide molecules as thought before.

Bacterial taxonomy

Van Niel also played a key role in the development of

bacterial taxonomy Bacterial taxonomy is the taxonomy, i.e. the rank-based classification, of bacteria. In the scientific classification established by Carl Linnaeus, each species has to be assigned to a genus ( binary nomenclature), which in turn is a lower level ...

. In 1962, van Niel in collaboration with

Roger Y. Stanier Roger Yate Stanier (22 October 1916 – 29 January 1982) 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 contribut ...

defined

prokaryotes A prokaryote () is a single-celled organism that lacks a nucleus and other membrane-bound organelles. The word ''prokaryote'' comes from the Greek πρό (, 'before') and κάρυον (, 'nut' or 'kernel').Campbell, N. "Biology:Concepts & Conn ...

as cells in which the nuclear material is not surrounded by a

nuclear membrane The nuclear envelope, also known as the nuclear membrane, is made up of two lipid bilayer membranes that in eukaryotic cells surround the nucleus, which encloses the genetic material. The nuclear envelope consists of two lipid bilayer membra ...

, a definition that is still used to date.

Teaching

Shortly after his arrival at

, van Niel developed a course in general microbiology which was to become widely influential. During its run from 1938 to 1962, the course drew students from around the world, and included several accomplished scientists among its alumni, including

Esther Lederberg Esther Miriam Zimmer Lederberg (December 18, 1922 – November 11, 2006) was an American microbiologist and a pioneer of bacterial genetics. She discovered the bacterial virus λ and the bacterial fertility factor F, devised the first imp ...

and Allan Campbell. and Arthur Kornberg, the recipient of the 1959 Nobel prize for DNA synthesis.

Scientific legacy and awards

Van Niel was the first biologist to receive the American

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 scienc ...

; he was awarded the 1963 Medal in biological sciences for "his fundamental investigations of the comparative biochemistry of microorganisms, for his studies of the basic mechanisms of photosynthesis, and for his excellence as a teacher of many scientists." Additional awards include: * 1955:

Marjory Stephenson Prize The Marjory Stephenson Prize is the principal prize of the Microbiology Society, awarded for an outstanding contribution of current importance in microbiology. Marjory Stephenson was the second president of the Microbiology Society (1947 - 1949) a ...

of the

Society for General Microbiology The Microbiology Society (previously the Society for General Microbiology) is a learned society based in the United Kingdom with a worldwide membership based in universities, industry, hospitals, research institutes and schools. It is the large ...

* 1966:

Charles F. Kettering Charles Franklin Kettering (August 29, 1876 – November 25, 1958) sometimes known as Charles Fredrick Kettering was an American inventor, engineer, businessman, and the holder of 186 patents. For the list of patents issued to Kettering, see, Le ...

Award of the

American Society of Plant Biologists American(s) may refer to: * American, something of, from, or related to the United States of America, commonly known as the "United States" or "America" ** Americans, citizens and nationals of the United States of America ** American ancestry, pe ...

* 1967:

Rumford Prize Founded in 1796, the Rumford Prize, awarded by the American Academy of Arts and Sciences, is one of the oldest scientific prizes in the United States. The prize recognizes contributions by scientists to the fields of heat and light. These terms ...

* 1970:

Leeuwenhoek Medal The Leeuwenhoek Medal, established in 1877 by the Royal Netherlands Academy of Arts and Sciences (KNAW), in honor of the 17th- and 18th-century microscopist Antoni van Leeuwenhoek, is granted every ten years to the scientist judged to have made th ...

In 1950 van Niel became a correspondent of the

Royal Netherlands Academy of Arts and Sciences The Royal Netherlands Academy of Arts and Sciences ( nl, Koninklijke Nederlandse Akademie van Wetenschappen, abbreviated: KNAW) is an organization dedicated to the advancement of science and literature in the Netherlands. The academy is housed ...

Selected publications

Footnotes

External links

National Academies Press BiographyMemorial resolution
at Stanford University.

{{DEFAULTSORT:Niel, C. B. 1897 births 1985 deaths Dutch microbiologists Dutch biochemists American microbiologists Delft University of Technology alumni Stanford University faculty National Medal of Science laureates Leeuwenhoek Medal winners Scientists from Haarlem Members of the Royal Netherlands Academy of Arts and Sciences Dutch emigrants to the United States