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VA Nvan Neil, Cornelius B. NEIL, CORNELIUSB.(1897-1985)

Dutch microbiologist and teacher

Cornelius B. van Neil made pioneering contributions to the

study of photosynthesisin the bacteriathat are known as the

purple and green sulfur bacteria. These rather exotic bacteria

are plant-like in that they use specific wavelengths of sunlight

as a source of energy, instead of the metabolismof carbon-

containing compounds. In addition to his research contribu-

tions, van Neil is noteworthy because of his tremendous

teaching contributions. He inspired many people to take up a

career in research microbiology in the first half of the twenti-

eth century. Several of his students went on to obtain the

Nobel Prize for their scientific contributions.

Van Neil was born in Haarlem, The Netherlands. His

interest in chemistry was sparked while he was still in high

school. This interest led him to enroll in the Chemistry Division

of the Technical University of The Netherlands. His education

was interrupted by a brief stint in the Dutch army. But ulti-

mately he received a degree in Chemical Engineering in 1923.

He then became a laboratory assistant to Albert Jan Kluyver, a

renowned microbial physiologist and taxonomist. van Neil was

responsible for the culturecollection of yeast, bacteria, and

fungithat Kluyver has amassed. During this time, van Neil iso-

lated Chromatium spp.and Thiosarcina roseaand demonstrated

that their growth did not involve the production of oxygen.

van Neil received a Ph.D. from The Technical University

in 1928 for his research on proprionic acid bacteria (now well-

known as one of the causes of acne). Following this, he came

to the United States to accept a position at the Hopkins Marine

Station, a research institution of Stanford University located on

the Monterey Peninsula. He remained at Hopkins until his

retirement in 1962. From 1964 until 1968, he was a visiting

Professor at the University of California at Santa Cruz. He then

retired from teaching and research entirely.

During his tenure at the Hopkins Marine Station, van

Neil produced his most fundamentally important work. He was

able to demonstrate that the ability of purple and green sulfur

bacteria to exist without oxygen depends on the presence of

sunlight. The photosynthetic reaction causes carbon dioxide to

become reduced, providing the building blocks needed by the

bacteria for growth and division. van Neil went on to broaden

his work to photosynthesis in general. His observations that

radiant energy activates a hydrogen donating compound

instead of carbon dioxide was seminal in the development of

subsequent studies of photosynthetic reactions in nature.

Another area where van Neil made a fundamental con-

tribution was the emerging field of bacterial classification.

Through his efforts in identifying over 150 strains of bacteria,

and consolidating these organisms into six species contained

within the two genera of Rhodopseudomonasand Rhodo-spir-

illum, van Neil and Kluyver laid the groundwork for the use of

bacterial physical and chemical characteristics as a means of

classifying bacteria.

van Neil’s teaching legacy is as important as his

research contributions. He established the first course in gen-

eral microbiology in the United States. He was a riveting lec-

turer, and his classes could last an entire day. He taught and

mentored many students who went on to considerable

achievements of their own.

See alsoMicrobial taxonomy; Photosynthetic microorganisms

NEISSERIA •seeGONORRHEA

NEOMYCIN•seeANTIBIOTICS

NEURAMINIDASE(NA)•seeHEMAGGLUTININ

(HA) AND NEURAMINIDASE(NA)

NNeurosporaEUROSPORA

The bread moldNeurospora crassais a simple fungal eukary-

ote which has been used extensively as a model organism to

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