PURIFICATION AND PROPERTIES OF THREE RIBONUCLEASES FROM RABBIT BRAIN NUCLEI
Abstract
THE PURIFICATION AND PROPERTIES OF THREE RIBONUCLEASES FROM RABBIT BRAIN NUCLEIIS REPORTED IN THE PRESENT THESIS. THE ENZYMES, CALLED RIBONUCLEASES A1, A2 AND B RESPECTIVELY ARE EXTRACTED FROM NUCLEI BY MEANS OF 0.5 M NACL AND PURIFIED BY A SERIES OF ION EXCHANGE AND AFFINITY CHROMATOGRAPHY STEPS. THE RIBONUCLEASES DISPLAY OPTIMAL ACTIVITY AT NEAR NEUTRAL PH IN THE PRESENCE OF 50-80 MM NACL AND DO NOT REQUIRE BIVALENT IONS. THEY ARE ENDONUCLEASES AND THEIR HYDROLYSIS PRODUCTS BEAR A FREE 5' HYDROXYL GROUP, WHILE THE TERMINAL PHOSPHATE IN ENZYMES A1 AND A2 IS MONOESTERIFIED AT THE 3' POSITION AND IN ENZYME B IS DIESTERIFIED AT POSITIONS 2' AND 3'. IN ORDER TO ESTABLISH THEIR BASE SPECIFICITY, THE ENZYMES HAVE BEEN ALLOWED TO ACT ON DIFFERENT SUBSTRATES SUCH AS DINUCLEOSIDE MONOPHOSPHATES, DEPHOSPHORYLATED TRINUCLEOTIDES, HOMOPOLYRIBONUCLEOTIDES AND 5 S RNA FROM E. COLI. RNASE A1 CLEAVES PREFERENTIALLY APN BONDS, RNASE A2 WAS FOUND TO BE PYRIMIDINE SPECIFIC IN THAT IT PREFERENTIALLY CLEA ...
show more
Download full text in PDF format (6.3 MB)
(Available only to registered users)
|
All items in National Archive of Phd theses are protected by copyright.
|
Usage statistics
VIEWS
Concern the unique Ph.D. Thesis' views for the period 07/2018 - 07/2023.
Source: Google Analytics.
Source: Google Analytics.
ONLINE READER
Concern the online reader's opening for the period 07/2018 - 07/2023.
Source: Google Analytics.
Source: Google Analytics.
DOWNLOADS
Concern all downloads of this Ph.D. Thesis' digital file.
Source: National Archive of Ph.D. Theses.
Source: National Archive of Ph.D. Theses.
USERS
Concern all registered users of National Archive of Ph.D. Theses who have interacted with this Ph.D. Thesis. Mostly, it concerns downloads.
Source: National Archive of Ph.D. Theses.
Source: National Archive of Ph.D. Theses.