"Established DNA as Genetic Material" Rollin Hotchkiss Hand Written Note For Sale

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"Established DNA as Genetic Material" Rollin Hotchkiss Hand Written Note:
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Up for sale "Established DNA as Genetic Material" Rollin Hotchkiss Hand Written Note.

ES-4827

Rollin

Douglas Hotchkiss (1911

– December 12, 2004) was an American biochemist who helped to establish the

role of DNA as the genetic material and contributed to the isolation and

purification of the first antibiotics. His work on bacterial transformation helped

lay the groundwork for the field of molecular genetics. Hotchkiss

was born in South Britain, Connecticut. The son of factory workers, he attended Yale University after scoring the highest in the nation

on an achievement test.

Hotchkiss earned a B.S. in chemistry in 1932, and remained at Yale for a Ph.D.

in organic chemistry. After completing his doctoral work in 1935, Hotchkiss

became a fellow of the Rockefeller

Institute of Medical Research, where he would remain until

retirement in 1982.

At the Rockefeller Institute, Hotchkiss initially worked as an assistant

to Oswald Avery and Walter

Goebel, and was encouraged to learn more biology at a summer courses

at the Marine Biological

Laboratory. His early work isolating and synthesizing derivatives

of glucoronic acid led

to the identification of one of the specific polysaccharides in the capsule of type III pneumococci. Hotchkiss spent the 1937-1938 academic year in

the lab of Heinz Holter and Kaj Linderstrøm-Lang at Carlsberg Laboratory learning

protein analysis techniques. In 1938, he began collaborating with René Dubos to isolate and study antibiotics produced by

soil bacteria. Their work on gramicidin and tyrocidine led to the first commercial antibiotics, and

with Fritz Lipmann they

found that the antibiotics include D-amino acids. During

the late 1930s, Hotchkiss was also strongly critical of the Bergann–Niemann hypothesis of protein structure, the

proposal by fellow Rockefeller biochemists Max Bergmann and Carl Niemann that protein structures always consist of

multiples of 288 amino acids. (This would also be a feature of Dorothy Wrinch's cyclol hypothesis of protein structure). In

1946, in the wake of that DNA, not protein, had the power to

transform bacteria from one type to another, Hotchkiss rejoined Avery's lab.

His work on protein analysis helped answer Avery's critics who argued that the

experiment was not sufficiently rigorous to rule out protein contamination (and

thus the possibility that protein was the transforming factor). Hotchkiss found

that virtually all the detected nitrogen in the purified DNA used in for the

transformation experiments came from glycine, a breakdown product of the nucleotide base adenine, and estimated that undetected protein contamination

was at most .02%, although he did not publish this result until 1952 (the year

of the Hershey–Chase experiment).

In 1948 Hotchkiss used paper chromatography to

quantify the base composition of DNA and, independently of Erwin Chargaff, found that the base ratios differed from

species to species.

In 1951, Hotchkiss showed that purified bacterial DNA could be used one

strain of bacteria to another without changing the capsule type (the main

identifying feature of different types of the same bacterial species). His

subsequent worked helped establish the basics of bacterial genetics, showing

that many features of classical genetics (including genetic linkage) have parallels in bacteria, despite their

lack of chromosomes. Hotchkiss continued working

in molecular genetics until his retirement in 1982, including significant

collaborations with Julius Marmur, Maurice Fox, Alexander

Tomasz, Joan and his the mid-1960s, Hotchkiss became interested in the potential dangers

of genetic engineering (a

term he helped to popularize). Through the early 1970s he articulated many of

the concerns that led to the 1975 Asilomar

Conference on Recombinant DNA.

Hotchkiss was a member of the American

Academy of Arts and Sciences and the National Academy of

Sciences (elected in 1961), and served as president of

the Genetics Society of

America from 1971 to 1972. After leaving Rockefeller University

in 1982, he worked as a research professor at the University at Albany, SUNY until

retiring to Lenox, Massachusetts in

1986. Hotchkiss died December 12, 2004 of congestive heart failure. 

"Established DNA as Genetic Material" Rollin Hotchkiss Hand Written Note

$349.99