Average molecular mass of amino acid in E. coli protein

Value 109 Da Range: Table - link Da
Organism Bacteria Escherichia coli
Reference Spahr PF. Amino acid composition of ribosomes from Escherichia coli. J Mol Biol. 1962 May4: 395-406. p.405 table 6PubMed ID13915520
Method The average amino acid molecular mass was calculated by averaging the left column of the table: Sum of [(fraction of each amino acid)X(amino acid's molecular mass)]. Note: this value is different than that given by Neidhardt (108 Da), tablelink - link , footnote h, BNID 103890, 104878, 104879, 104880
Comments "The protein was prepared from the ribosomes in two different ways. In the first, the acetic acid procedure, the protein was extracted by 66% acetic acid in the cold, according to Fraenkel-Conrat (1957) and as described by Waller & Harris (1961) The second method, referred to hereafter as the RNase procedure, made use of the fact that there is a latent RNase in the ribosomes (Elson, 1958) ...Samples of protein or ribosomes were hydrolysed with glass redistilled constant-boiling HCI (0.5 ml. for every 3 mg protein) under nitrogen in sealed Pyrex glass tubes in an oven maintained at 110±1°C for 24 and 72 hr, and, in some cases, for 96 hr."
Entered by Uri M
ID 104877