Historic nucleic acids isolated by Friedrich Miescher contain RNA besides DNA

Area of Science:

• Molecular Biology
• Biochemistry
• Genetics

Background:

• Friedrich Miescher discovered DNA in 1869, isolating
• Nuclein
• from human pus cells.
• He recognized Nuclein as a distinct molecule, noting its acidic properties, high molecular weight, and phosphorus content.
• Miescher's work laid the groundwork for understanding the nucleus and its role in heredity.

Purpose of the Study:

• To investigate whether Friedrich Miescher's original isolation of "Nuclein" also included ribonucleic acid (RNA).
• To re-evaluate Miescher's discovery in light of modern understanding of nucleic acids.
• To determine the full scope of Miescher's contribution to molecular genetics.

Main Methods:

• Reproduced Miescher's historic protocols for isolating "Nuclein" using modern techniques.
• Analyzed a sample of historic Nuclein isolated by Miescher from salmon sperm.
• Utilized Liquid Chromatography-Ultraviolet Mass Spectrometry (LC-UV-MS) to detect uracil, a component of RNA.

Main Results:

• The reproduced isolation yielded a significant percentage of RNA alongside DNA.
• Analysis of Miescher's historic Nuclein sample revealed significant levels of uracil.
• The presence of uracil indicates that Miescher's original isolate contained RNA.

Conclusions:

• Friedrich Miescher's discovery of "Nuclein" included both deoxyribonucleic acid (DNA) and ribonucleic acid (RNA).
• This finding underscores the fundamental and comprehensive nature of Miescher's initial discovery.
• Miescher's work is foundational to the entire field of molecular genetics, encompassing both major nucleic acids.