Definition. Fick, unit of diffusion equivalent to 10−7 cm2· s−1.
Purification, molecular and enzymic characterization of an acid RNase from the insect Ceratitis capitata
Article first published online: 3 MAR 2005
European Journal of Biochemistry
Volume 158, Issue 2, pages 367–370, July 1986
How to Cite
GARCÍA-SEGURA, J. M., OROZCO, M. M., FOMINAYA, J. M. and GAVILANES, J. G. (1986), Purification, molecular and enzymic characterization of an acid RNase from the insect Ceratitis capitata. European Journal of Biochemistry, 158: 367–370. doi: 10.1111/j.1432-1033.1986.tb09760.x
Note. Portions of this paper (including Materials and Methods, Tables 1 and 3, and Figs 1, 5, 6 and 7) are presented in miniprint at the end of the paper.
- Issue published online: 3 MAR 2005
- Article first published online: 3 MAR 2005
- (Received January 27, 1986) – EJB 860081
An acid ribonuclease has been purified from the insect Ceratitis capitata. The specific activity of the purified enzyme is 580 units/mg. This enzyme is a single polypeptide chain of about 35.5 kDa, containing only one disulfide bridge and no free – SH groups. The A0.1%1 cm at 280 nm is 1.90. The hydrodynamic radius of the native enzyme is 2.5 nm. The secondary structure of this RNase is composed of 10%α-helix, 31%β-structure and 59% aperiodic conformation with an average number of residues per helical segment of 10, based on circular dichroic measurements. Optimum parameters for the enzyme activity are pH 5.5, 0.15 M ionic strength and 40°C. Divalent cations are not required for the enzymic catalysis. This enzyme has been characterized as cyclizing endoribonuclease.