I'm interested in the most abundant proteins inside cells by total mass of the protein (for example average for a whole human or for specific organs/tissues/cell lines).
It is quite easy to find that the largest % by mass in the human body is collagen (25 to 35% of total body protein). Collagen is an extracellular protein; finding the same info for intracellular proteins has been surprisingly difficult. Finding what is the second largest %, or a top 10 list, has also been difficult.
In the process of searching, I found PaxDb which lists protein abundance by "ppm", or counts divided by the total counts. It is quite hard to convert that to % by mass - it would be necessary to know the molecular mass of every protein (for example by matching them with entries in UniProt), and then multiply count by molecular mass. Another resource which seems to have a lot of data is PeptideAtlas, but I can't tell how to extract either counts or masses from that.
Is there a canonical list of (eg) top 10 or top 100 intracellular proteins by mass in a whole human? How about the same by organ/tissue?