[Extracellular ribonuclease from Bacillus thuringiensis].
The ability of the strain Bacillus thuringiensis var. subtoxicus to produce extracellular ribonuclease (ribonuclease Bt) was studied. It was found that the culture medium possesses a RNA-depolymerizing activity whose maximum is observed 4-5 hours after the beginning of the linear growth phase. A three-step chromatography of the culture extract on phosphocellulose resulted in a homogeneous enzyme with a molecular mass of 12000 Da. The enzyme showed the maximum activity towards RNA at pH 8.5, catalyzed the hydrolysis of polyribonucleotides and guanosine-2',3'-cyclophosphate. Hence, the enzyme can be related to base-nonspecific cyclizing ribonucleases showing the guanylic specificity towards nucleoside-2',3'-cyclophosphates.
Chepurnova
N K
NK
Liakhov
D L
DL
Rechinskiĭ
V O
VO
Karpeĭskiĭ
M Ia
MIa
D001413:Bacillus thuringiensis / Q000201:enzymology*; D004591:Electrophoresis, Polyacrylamide Gel; D012260:Ribonucleases / Q000302:isolation & purification*; D013379:Substrate Specificity
D012260:Ribonucleases
Vnekletochnaia ribonukleaza iz Bacillus thuringiensis.