About Focus Proteomics
Focus Proteomics LLC is a contract service organization specializing in 2D gel electrophoresis and protein characterization. Our scientific team has over 100 years combined experience in protein electrophoresis and proteomics with over 800 publications in the field of protein biochemistry. Focus Proteomics has provisional patent on its iFOCUS™ Next Generation IEF technology.
Focus Proteomics offers characterization of protein biologics such as confirmation of purity, the detection of host cell contaminants (HCPs), and the detection of important post-translational modifications that can impact drug stability or efficacy. |
Same genome, different proteome
There is clear lack of correspondence between genome size and the complexity of organisms. For example, the human genome is comprised of roughly 20,000 genes, compared to a grape which has over 30,000 genes [1]. Protein expression levels cannot be predicted DNA sequence. Likewise, mRNA expression levels often correlate very poorly with protein expression levels [2]. Moreover, neither DNA nor mRNA analyses can predict the many possible post-translational modifications of proteins. Thus, only protein expression analysis can reveal changes in global protein expression that occur in response to environmental stimuli and during disease processes. In its November 2018 release, UniProt/trEMBL reported 137,213,158 sequence entries comprised of 46,053,137,524 amino acids in its protein database. At the rate of 20 amino acids per second, a single prokaryotic ribosome working non-stop would require over 72 years to translate the entire database. However, there is evidence at the protein level for only 0.11% of the total entries [3]. The vast majority of protein sequences are predicted or inferred from homology. Human sequences comprise less than 1% of the database. |
References
[1] Pertea M, Salzberg SL (2010). Between a chicken and a grape: estimating the number of human genes. Genome Biol. 11, 206.
[2] Smejkal GB (2012). Genomics and proteomics: Of hares, tortoises, and the complexity of tortoises. Expert Rev. Proteomics, 9, 469-472.
[3] UniProtKB/TrEMBL Protein Database Release Statistics, (2018). www.ebi.ac.uk/uniprot/TrEMBLstats
[2] Smejkal GB (2012). Genomics and proteomics: Of hares, tortoises, and the complexity of tortoises. Expert Rev. Proteomics, 9, 469-472.
[3] UniProtKB/TrEMBL Protein Database Release Statistics, (2018). www.ebi.ac.uk/uniprot/TrEMBLstats