Specific UV-absorbancy of pure rRNA isolated from trout liver as a standard for the quantification of ribonucleic acid from fish tissues.
1. Lyophilized crude rRNA from trout (Salmo gairdneri R.) liver was composed (w/w) of 2.9% protein, traces of DNA and glycogen, 13% water and 83% pure rRNA. The RNA content was derived from the discrepancy between effectively found (8.1%, w/w) and theoretical phosphorus content (9.6%, w/w). 2. The theoretical phosphorus content was calculated on the basis of the molar distribution of nucleotides in rRNA (UMP:GMP:AMP:CMP = 24.7%:30%:19.5%:25.8%), established upon cation exchange chromatography of alkali-degraded crude rRNA. 3. The extinction coefficient (corrected for moisture and none-ribonucleic acid contaminants) of pure rRNA in 0.2 N PCA after digestion in 0.3 N KOH at 37 degrees C for 90 min is 361 in terms of E1%260. That of undegraded, pure rRNA in water amounts to 279.
Simon
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Department of Zoophysiology, University of Kiel, FRG.
D000818:Animals; D002852:Chromatography, Ion Exchange; D005399:Fishes / Q000235:genetics*; D005612:Freeze Drying; D008099:Liver / Q000032:analysis*; D012335:RNA, Ribosomal / Q000302:isolation & purification / Q000592:standards*; D012015:Reference Standards; D012487:Salmonidae / Q000235:genetics*; D013045:Species Specificity; D013056:Spectrophotometry, Ultraviolet / Q000379:methods; D014337:Trout / Q000235:genetics*
D012335:RNA, Ribosomal