Karl Ludwig Wilhelm Otto Schultzen (16 July 1837 – 7 December 1875) was a German physician born in Lissa

Leszno

Leszno is a town in central Poland with 63,955 inhabitants . Situated in the southern part of the Greater Poland Voivodeship since 1999, it was previously the capital of the Leszno Voivodeship . The town has county status.-History:...

.

He studied medicine at the Universities of Königsberg

University of Königsberg

The University of Königsberg was the university of Königsberg in East Prussia. It was founded in 1544 as second Protestant academy by Duke Albert of Prussia, and was commonly known as the Albertina....

 and Berlin, earning his doctorate in 1862 with the thesis Deinanition, accedit observatio et exploratio microscopica. Afterwards he was an assistant to Friedrich Theodor von Frerichs (1819–1885) at the medical clinic in Berlin

Berlin

Berlin is the capital city of Germany and is one of the 16 states of Germany. With a population of 3.45 million people, Berlin is Germany's largest city. It is the second most populous city proper and the seventh most populous urban area in the European Union...

. He gained his habilitation in
1867, and in 1871 became a professor of clinical medicine at the University of Dorpat. He died four years later at the age of 38.

With Marceli Nencki

Marceli Nencki

Wilhelm Marceli Nencki was a famous Polish chemist and doctor.-Work:Nencki's main scientific interest concentrated on urea synthesis, the chemistry of purines and biological oxidation of aromatic compounds. He was also interested in the structure of proteins, enzymatic processes in the intestine...

 (1847–1901) he performed physiological studies of urea

Urea

Urea or carbamide is an organic compound with the chemical formula CO2. The molecule has two —NH2 groups joined by a carbonyl functional group....

, discovering that amino acids (glycine

Glycine

Glycine is an organic compound with the formula NH2CH2COOH. Having a hydrogen substituent as its 'side chain', glycine is the smallest of the 20 amino acids commonly found in proteins. Its codons are GGU, GGC, GGA, GGG cf. the genetic code.Glycine is a colourless, sweet-tasting crystalline solid...

 and leucine

Leucine

Leucine is a branched-chain α-amino acid with the chemical formula HO2CCHCH2CH2. Leucine is classified as a hydrophobic amino acid due to its aliphatic isobutyl side chain. It is encoded by six codons and is a major component of the subunits in ferritin, astacin and other 'buffer' proteins...

) are intermediate links between protein

Protein

Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...

 and urea

Urea

Urea or carbamide is an organic compound with the chemical formula CO2. The molecule has two —NH2 groups joined by a carbonyl functional group....

., With Bernhard Naunyn

Bernhard Naunyn

Bernhard Naunyn was German pathologist who was born in Berlin. After receiving his degree at the University of Berlin in 1863, he became an assistant to pathologist Friedrich Theodor von Frerichs...

 (1839–1925) he conducted important research involving the behavior of benzene

Benzene

Benzene is an organic chemical compound. It is composed of 6 carbon atoms in a ring, with 1 hydrogen atom attached to each carbon atom, with the molecular formula C6H6....

-derived hydrocarbons in the body.