40S subunit ~25,000Å^2: 30S subunit ~6,500Å^2 Å^2
||Rabl J, Leibundgut M, Ataide SF, Haag A, Ban N. Crystal structure of the eukaryotic 40S ribosomal subunit in complex with initiation factor 1. Science. 2011 Feb 11 331(6018):730-6. doi: 10.1126/science.1198308. p.733 left column top paragraphPubMed ID21205638
||p.732 right column bottom paragraph to p.733 middle column:"In bacteria, five of 20 ribosomal proteins interact with no other ribosomal protein. By contrast, all ribosomal proteins of the T. thermophila 40S subunit contact at least one other ribosomal protein (table S5), and the total interaction surface between ribosomal proteins in the 40S subunit is almost four times the 30S ribosomal protein-protein interaction surface (40S, ~25,000 Å^2 30S, ~6500 Å^2) (table S5). Although the increased number of ribosomal proteins in the 40S is partly responsible for the larger interaction surface, the average interaction surface of a eukaryotic protein is nonetheless larger than a bacterial protein in the 30S subunit by a factor of 2.4."