Microbiology and Immunology

WORLD OF MICROBIOLOGY AND IMMUNOLOGY Jenner, Edward

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operon (or lac operon as it is called), this regulator gene codes

for a repressor protein. The repressor protein does one of two

things. When no lactose is present, the repressor protein

attaches to the operator and inactivates it, in turn, halting

structural gene activity and protein synthesis. When lactose is

present, however, the repressor protein binds to the regulator

gene instead of the operator. By doing so, it frees up the oper-

ator and permits protein synthesis to occur. With a system such

as this, a cell can adapt to changing environmental conditions,

and produce the proteins it needs when it needs them.

A year after publication of this paper, Jacob won the

Charles Leopold Mayer Prize of the French Academy of

Sciences. In 1964, Collège de France also recognized his

accomplishments by establishing a special chair in his honor.

His greatest honor, however, came in 1965 when he, Lwoff,

and Monod shared the Nobel Prize for Physiology or

Medicine. The award recognized their contributions “to our

knowledge of the fundamental processes in living matter

which form the bases for such phenomena as adaptation,

reproduction and evolution.”

During his career, Jacob wrote numerous scientific pub-

lications, including the books The Logic of Life: A History of

Hereditaryand The Possible and the Actual.The latter, pub-

lished in 1982, delves into the theory of evolution and the line

that he believes must be drawn between the use of evolution

as a scientific theory and as a myth.

See alsoBacteriophage and bacteriophage typing; Evolution

and evolutionary mechanisms; Evolutionary origin of bacteria

and viruses; Genetic regulation of eukaryotic cells; Genetic

regulation of prokaryotic cells; Immunogenetics; Molecular

biology and molecular genetics; Molecular biology, central

dogma of; Viral genetics

JANNASCH, HOLGERWINDEKILDE

(1927-1998)Jannasch, Holger Windekilde

German marine microbiologist

Holger Jannasch was a marine microbiologist who made fun-

damental contributions to the study of microbial life in the

extreme environment of the deep-sea. His discoveries helped

reveal a hitherto unknown type of bacterial growthand broad-

ened human knowledge about the diversity of life on Earth.

Jannasch was born in Holzminden, Germany. After a

short stint as a lumberjack, he returned to school. His educa-

tional experiences and a job as a warden at a coastal bird sanc-

tuary stimulated an interest in both biological life and the

ocean. These interests were pursued during graduate studies at

the University of Göttingen. He received his Ph.D. in biology

in 1955. From 1956 to 1960 he was an assistant scientist at the

Max Planck Society. At the same time he was also a post-doc-

toral fellow at the Scripps Institution of Oceanography in San

Diego, California, and at the University of Wisconsin. From

1961 to 1963 he served as an assistant professor in the

Department of Microbiology at the University of Göttingen.

He also held the position of Privatdozent at that University

from 1963 until his death.

Visits to the Woods Hole Oceanographic Institution in

the early 1960s lead to his joining the institution in 1963. He

remained there for the remainder of his career and life.

While at Woods Hole, Jannasch proved to be a consum-

mate mentor and educator. As well, he was a prolific researcher.

His main interests were the growth of microorganismsin the

sea, the existence of microbes at the low temperature and high

pressure of the ocean depths, and the microbial processes taking

place at hydrothermal ventson the ocean floor. Indeed, it was

Jannasch who discovered hydrothermal vents.

Jannasch’s research on the hydrothermal vents and their

associated bacterial populations became classic papers that

inspired other microbiologists to similar research. His discov-

ery of sulfur-utilizing bacteria that support an entire

hydrothermal ecosystem has had major implications for deep

sea microbial ecology and may be of fundamental importance

to providing insight into the origin of lifeon Earth.

Jannasch was also a seminal influence of the field of

microbial ecology. He was a participating author on some 200

research publications. For these and other accomplishments in

microbial ecology, a new microorganism was named for him

in 1966: Methanococcus jannaschii. That same year Woods

Hole established the Holger W. Jannasch Chair in recognition

of his accomplishments.

Many other awards and honors were bestowed on

Jannasch during his career. Foe example, in 1995 he was one

of only a handful of non-United States citizens elected to the

National Academy of Sciences.

See alsoExtremophiles

JJenner, Edward ENNER, EDWARD(1749-1823)

English physician

Edward Jenner discovered the process of vaccination, when he

found that injection with cowpoxprotected against smallpox.

His method of immunizationvia vaccination ushered in the

new science of immunology.

Jenner was born in Berkeley, England, the third son and

youngest of six children of Stephen Jenner, a clergyman of the

Church of England. He was orphaned at age five and was

raised by his older sister, who was married to a clergyman.

When Jenner was thirteen years old, he was apprenticed to a

surgeon. Then in 1770, he moved to London, England, to work

with John Hunter (1728 – 1798), an eminent Scottish anatomist

and surgeon who encouraged Jenner to be inquisitive and

experimental in his approach to medicine. Jenner returned to

Berkeley in 1773, and set up practice as a country doctor.

During and prior to Jenner’s lifetime, smallpox was a

common and often fatal disease worldwide. Many centuries

before Jenner’s time, the Chinese had begun the practice of

blowing flakes from smallpox scabs up the nostrils of healthy

persons to confer immunityto the disease. By the seventeenth

century, the Turks and Greeks had discovered that, when

injected into the skin of healthy individuals, the serum from the

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