Size Relationship Among Similar Proteins Association and Dissociation Reactions of Protein Units

A quarter of a century ago it was generally assumed that the proteins consisted of particles varying considerably in size. It was therefore quite unexpected when Svedberg and Fåhraeus (1926) and Svedberg (1926) found that all the proteins first studied in the ultracentrifuge appeared to be monodisperse and to have definite molecular weights (M). This finding of Svedberg stimulated him and his pupils to investigate a large number of proteins in the ultracentrifuge. Since at that time the light absorption method was the most convenient to use, it was advantageous to study colored proteins and therefore a number of chromo-proteins were the first to be investigated. Soon it appeared to Svedberg that the M found often were multiples of 35,000. A lot of work was therefore done on the study of proteins from various sources in order to disprove or prove the validity of a multiple hypothesis for the molecular...