Number of proteins per cell volume

Range ≈3,000,000 proteins/µm^3
Organism Generic
Reference Milo R. What is the total number of protein molecules per cell volume? A call to rethink some published values. Bioessays. 2013 Dec35(12):1050-5. doi: 10.1002/bies.201300066 p.1051 figure 1PubMed ID24114984
Method For A back of the envelope calculation of the number of proteins per cell volume see Table - link Abstract: "Here, [investigators] estimate the expected total number of proteins per unit of cell volume using known parameters related to the composition of cells such as the fraction of cell mass that is protein, and the average protein length. Using simple arguments, [they] estimate a range of 2-4 million proteins per cubic micron (i.e. 1 fL) in bacteria, yeast, and mammalian cells."
Comments P.1051 middle column bottom paragraph: "[Investigators’] first method of estimate is shown as a back‐of‐the‐envelope calculation in Fig. 1 using rounded “generic” parameter values. The estimate relies on knowledge of the protein mass per unit volume (denoted by cp). The units of cp are [g protein]/[mL cell volume] and this parameter has been reported for different cell types (see e.g. ref 20 and also BNID 105938, where here and later in this manuscript pointers for directly assessing values from the literature are given using the BioNumbers database identifiers ref 21, www.bionumbers.hms.harvard.edu). [Investigators] denote by laa the average length, in amino acids, of a protein, and the average mass of an amino acid by maa. The number of proteins per unit volume is equal to: N/V = cp/(laa × maa)."
Entered by Uri M
ID 115721