Towards completion of the Earth's proteome.
New protein sequences are deposited in databases at an accelerating pace; however, many of these are homologous to known proteins and could be considered redundant. If all historical releases of the protein database are analysed using the original sequence-clustering procedure described here, the fraction of newly sequenced proteins that are redundant is increasing. We interpret this as an indication that the sequencing of the Earth's proteome--the complete set of proteins on Earth--is approaching completion. We estimate the approximate size of the Earth's proteome to be 5 million sequences, most of which will be identified during the next 5 years. As the Earth's proteome nears completion, cluster analysis of the protein database will become essential to identify under-explored taxa to which future sequencing efforts should be directed and to focus research on protein families without experimental characterization.
Perez-Iratxeta
Carolina
C
Department of Molecular Medicine, Ottawa Health Research Institute, 501 Smyth Road, Ottawa, Ontario K1H 8L6, Canada.
Palidwor
Gareth
G
Andrade-Navarro
Miguel A
MA
D000818:Animals; D030562:Databases, Protein; D006801:Humans; D010802:Phylogeny; D011506:Proteins / Q000032:analysis / Q000737:chemistry / Q000145:classification; D020543:Proteome / Q000032:analysis*; D040901:Proteomics / Q000379:methods*; D020539:Sequence Analysis, Protein / Q000379:methods
D011506:Proteins; D020543:Proteome