nuclein

n. nucleus; protein of cell nuclei

A nucleic acid is a macromolecule composed of nucleotide chains. In biochemistry these molecules carry genetic information or form structures within cells. The most common nucleic acids are deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). Nucleic acids are universal in living things, as they are found in all cells. They are also found in viruses.
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(n.)
A constituent of the nuclei of all cells. It is a colorless amorphous substance, readily soluble in alkaline fluids and especially characterized by its comparatively large content of phosphorus. It also contains nitrogen and sulphur.
  

NUCLEINA