A ribonuclease from human seminal plasma active on double-stranded RNA.
A ribonuclease, active on single- and double-stranded RNAs, has been isolated from human seminal plasma 3-5 micrograms of enzyme were recovered per ml of seminal plasma, equivalent to 71% of total activity and a 2500-fold purification (measured with poly(A) X poly(U) as substrate) from the initial dialyzed material. Similar amounts of RNAase were found per g (wet weight) of human prostate, where the enzyme appears to be produced. Human seminal RNAase degrades poly(U) 3-times faster than poly(A) X poly(U), and poly(C) or viral single-stranded RNA about 10-times faster than poly(U). Degradation of poly(A) X poly(U), viral double-stranded RNA, and poly(A) by human seminal RNAase is 500-, 380- and 140-times more efficient, respectively, than by bovine RNAase A. The enzyme, a basic protein with maximum absorbance at 276 nm, occurs in two almost equivalent forms, one of which is glycosylated. Mr values of the glycosylated and non-glycosylated form are 21000 and 16000, respectively. The amino-acid composition of the RNAase is very similar to that of human pancreatic RNAase. The same is true for the carbohydrate content of its glycosylated form.
D000596:Amino Acids / Q000032:analysis; D002241:Carbohydrates / Q000032:analysis; D002846:Chromatography, Affinity; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D006801:Humans; D008297:Male; D011467:Prostate / Q000201:enzymology; D012330:RNA, Double-Stranded / Q000378:metabolism*; D012260:Ribonucleases / Q000302:isolation & purification / Q000378:metabolism*; D012661:Semen / Q000201:enzymology*
D000596:Amino Acids; D002241:Carbohydrates; D012330:RNA, Double-Stranded; D012260:Ribonucleases